BE483616A - - Google Patents

Description

       

    <Desc / Clms Page number 1>
 



    "Telephone system"
This invention relates to telephone systems and particularly to systems in which long distance or long distance communications are established by means of automatic switchgear.



   The objects of this invention are to provide maximum efficiency in an interurban telephone system in which connections between incoming and outgoing trunk lines or trunks are made by the control and operation of automatic switches mounted on them. a number of racks in a telephone office, to simplify the establishment of long-distance communications in a minimum period of time, real.

   

  <Desc / Clms Page number 2>

 to economize in the operation of the interurban systems by the use of equipment units which are common to the interurban lines or incoming and outgoing junctions to control the automatic switches in the establishment of the connections between the said lines or junctions, and to provide a signaling system common to said incoming and outgoing lines or junctions to provide the location of the switches connected to the particular junctions.



   According to the present invention an interurban telephone system is provided with trains of automatic switches comprising inbound junctions from tandem offices and remote tandem offices connected to the arrival switches of the train and outgoing junctions going to. remote trunk offices and offices in the trunk area connected to the train exit switches, other switches operable in various combinations under the control of markers in a group common to the arrival switches and departure of the train to interconnect the switches associated with any incoming calling junction entering the train of switches and any free junction leaving the train of switches following a route given by the incoming calling junction,

   switches and other junction equipment being mounted on a large number of frames. A multi-frequency signaling system is provided for progressively transmitting signals to the marker giving the location of a switch connected to the calling incoming junction, the location of a switch connected to the chosen outgoing junction and the species of the frame on which these junctions are located,

   as well as to gradually transmit signals to direct the marker to drop one group of junctions and choose another.

  <Desc / Clms Page number 3>

 to try it. This signaling system is arranged to actuate and readjust the marker between successive signals to progressively choose units of apparatus associated with the calling incoming junctions and the selected outgoing junctions, in order to establish circuits between the marker. and said apparatus units to obtain a combination of switches and connection circuit routes between the switch of the calling inbound junction and the switch of the selected outbound junction.



   A feature of this invention consists of a telephone system in which an automatic switching long distance office comprises two sets of automatic switches each mounted on a number of racks, for interconnecting incoming lines from associated long distance offices. and outgoing lines to remote associated toll offices or outgoing lines to termination offices located in the area of the switched toll office,

   and a switch control device common to the two switch trains for choosing outgoing free lines coming from one or the other switch train according to the line selection records received on a driven line. calling and for controlling the operation of switches in one or the other train of switches for connecting between them a calling incoming line and an outgoing line chosen as registered.



   Another related feature of this invention is a system in which signals are transmitted to the common switch control device giving the location of switches connected to a calling incoming trunk or trunk and to a trunk or trunk line. outgoing junction chosen.



   Another related feature is a system in which the switch controller is

  <Desc / Clms Page number 4>

 automatically reset in response to the transmission of successive signals.



   Another related feature is a system in which the use of a circuit for transmitting switch location signals is later used to operate the switches connected to the calling incoming junction and to the selected outgoing junction.



   Another related feature is a system in which signals each comprising a plurality of current frequencies are automatically transmitted to the marker controller in response to input from an input or output switch, each signal being transmitted to a single conductor to control an equivalent number of appliance units in the controller to establish signal currents corresponding to the location of the entered switches.



   Another related peculiarity is the organization of this multi-frequency signaling system, in which there is an action in the marker in response to the transmitted signals, independent of the junction management devices, to choose coupling connections between the marker and the switches associated with the calling incoming junction and the selected outgoing junction.



   Another related feature is a system in which multi-frequency signaling directs the marker in testing outgoing trunk groups going to a particular office when those trunk groups are connected to switches on different frames in the switch trains.



   Another related feature consists of a system in which the marker control device and

  <Desc / Clms Page number 5>

 The signaling system are both reconnected automatically in response to successive signals, when lines or trunks in a group on one rack are busy and a group of trunk lines on another rack is available.



   Another related feature consists of a signal transmission system common to the incoming and outgoing switches of the office to direct the switch control device in the actuation of switches connected to an incoming call line and to a line. selected outgoing.



   Another related feature consists of an inbound signal transmission system common to the / outgoing lines of the office for successively transmitting a series of signal combinations for directing successive functional operations of a control device.



   These and other features will be discussed in more detail in the following description.



   Reference may be made to the accompanying drawings which illustrate the particular features of the invention and where
Figs. 1 to 8 inclusive are schematically shown when arranged as shown in FIG. 76, the circuit of an interurban system and Figs.



  9 to 75 inclusive, when arranged as shown in FIG. 77, show the detailed circuits of said system.



   In the detailed representation, Fig. 21 schematically illustrates the distant trunk offices connected by trunk interjunction junctions to the incoming trunk circuits of this office with which they establish a connection by signaling of different kinds.



   This figure also illustrates tandem junctions

  <Desc / Clms Page number 6>

 entering the office, coming from manual offices or at! ... '. nuisances and tandem junctions coming from an interurban switchboard n 3 located in the interurban area and; the junctions coming from service switchboards .



   An incoming junction; with auuel on the circuits has been shown in detail in Figs. 12 and 13 to illustrate the phases of the operation of the incoming junction which actuate the equipment of this long distance office.



   Fig. 22 illustrates cross-bar coupling switches used to connect directly.; Slow calling incoming junctions to any one of a number
 EMI6.1
 bre rJ. ' enr (-)!.; Ístr0u: rs-envoycurs arriving and attaching an outgoing trunk to any one of a number
 EMI6.2
 ci 1 e; 1r (. '' iGtrcurs-envoy (urs from: output.

   The crossbar coupling switches are usually interposed between the primary and secondary switches to allow a large number of possibilities in the choice for.
 EMI6.3
 the selection of s (mrc, '1 str; ", urf, -onvo: / (' ursli1 ') res.

   Lé.,, .7.i:;. 32 illusbre the co ,; Coli - :; lUlators with crossed bars used to connect incoming junctions from manual offices. ': - to the tracks entering the operator positions without cord.
 EMI6.4
 



  The. The 1;. 43 1¯: .li, l;, e.1 '(' u (control relay comprising: a start relay actuated by an incoming junction to establish a connection between the junc-
 EMI6.5
 t; 1.,. In E'ïl, i'élilvE, r = t a circuit ".L cO;, 1aandr.:, To operate the.:; (" L, r; l..titr \ .11'5 of cross coupling to obtain the link between an incoming junction and a free channel in one of the trunk positions without cords.



   It ens shown in FIG. 42 a connector actuated by
 EMI6.6
 1 f <y.a: '; ißla; e de la Fit ;. 4j to obtain the temporary use of a control circuit; coupling shown in Figs. 52, 53, 54, 32, 33, and 34. @

  <Desc / Clms Page number 7>

 
Fig. 55 illustrates a track circuit locking in the trunk position without cords. A number of these routes are shown schematically in these figures.
 EMI7.1
 The i.dr.) AY'E:

  111 '' E: from position C: 7Ll, ll; trl: jULlr the iablc: ".. The long distance operator switch is illustrated in Figs. $ 36, 35, 66, 71 and 72.
 EMI7.2
 



  An enT'f '. .l.: ii: 1'E'ul'-C'nVGyLit 'direct-'ient associated with each position without cords is illustrated in Figs. @ 3, 4, 33, 34, 44, 45, 57 and 67.



   Figs. 73 and 74 illustrate connectors capable of connecting a large number of conductors from any of a large number of these to a free tag in a common group of tags. A second is-spread marker shown schematically at Fig. 74.



   A marker combines long distance and termination
 EMI7.3
 is illustrated in Fi, s. 17 to 19,. '.' 7 G 3J 35 to 40, 40 51, 58 to II) 68,69,70 and 75.



   Fig. 20 illustrates a number of current sources and amplifiers for the multiple frequency signaling circuit.



   An intercity train of cross-bar switches is shown in Fig. 14 and also in the upper part of FIG. 15 by which communications are established between an incoming calling junction and a remote long distance office.



   A termination train of crossbar switches and shown in Figs. 9 and 10, by which calls are made from incoming trunks to offices located in the network of this toll center. Figs. 9-10 and 14 also schematically illustrate connectors and control relays for connecting a marker to the incoming secondary crossbar switches and to the output primary crossbar switches. The app

  <Desc / Clms Page number 8>

 The same and the circuits for this connector and this control unit for a pair of frames are shown in detail in the lower part of Fig. 15 and in Figs. 26 and 25.



   Fig. 11 illustrates in sufficient detail a discharge junction to actuate the apparatus of this system.



   Fig. 16 illustrates a trunk outgoing trunk in detail and schematically illustrates other outbound trunks and remote trunk offices which are reached from the trunk train of switches.



   Figs 31 and 41 show connectors, terminal block relays, branch jacks, and apparatus for expanding a group of outgoing junctions by associating the marker with a group of junctions on a different frame than the one on which is located the normal group of junctions going to an office. Outgoing trunk assignment rack connectors for associating a marker with relays known as terminal block relays or outgoing trunk group relays are shown in the lower portion of Fig.



  41. The relays governing this selection are also shown in FIG. 41. Multiple contact terminal block relays are shown at the bottom of FIG. 31. Slow branch jacks and devices for expanding the group of junctions are shown at the top of Fig.31. In the present system, automatic switches of the cross-bar type are shown for selectively making the desired connections, and these switches are controlled as common register-senders and recorders.
 EMI8.1
 common marks.

   The ::: 0 :::: JUta G (: crossbar urs, the

  <Desc / Clms Page number 9>

 
 EMI9.1
 recorders-senders and the l! lm'qu8urs used for co. "... 'an- der the said. ^. UIL.! Lité.i., 2 ^ S, the connectors' .ie; ,,;, 1 'c ..,' - '1., rio serving to connect the t' ': Ci?' Cl ', iGü1 "S to the dibs ellre; l.S1'C: U.1'J senders including the recorders-senders of the keypad and rack connectors which serve to associate the markers with the racks of crossbar switches, and the methods by which these switches are controlled in their selector operating operations are in many respects identical to those already known in this article. technical.



   General description.



   A toll office for this toll cross-bar switch system as shown: schematically in Figs 1 to 3 inclusive, includes two sets of cross-bar switches to establish connections between an incoming line or junction and a line
 EMI9.2
 or outgoing junction. urbi des tnÜns. of COII:, ;; t: .tateu:

  cross bar cs as shown in the top half of the FIES. 2 and 3, is intended to send telephone anpels to other distant long distance offices. In the lower half, Figs. 2 and 3, is shown a second train of crossbar switches for handling calls known as termination calls. These telephone calls can be initiated at a remote long distance office or service switchboard and routed to local office subscribers in the area of that particular long distance center.

   An exception to what is stated below is formed by tubular offices, which can be reached either by the interurban train or by; The termination switch, A tributary office can be defined as an office located in the area of the interurban center, but outside the maximum tariff zone of this area.

   Fig. 1 illustrates the various

  <Desc / Clms Page number 10>

 offices and switchboards from which calls can be made entering the long-distance office, for example, tandem calls launched in the vicinity of the inter-urban center are passed in the tandem switchboards shown schematically in 112 and 115. In this figure of
 EMI10.1
 TT 'Lt: s7 .; ilCG jU'LlCt.LUYIJ' tandem).

   Tandem calls are routed by the intercity train of crossbar switchers to outgoing trunk junctions, going to the remote trunk offices indicated schematically as 401, 403 and 405 or may be directed to a tributary office such as 416.

   Calls from automatic desks or key-operated desks or switchboards schematically indicated by 115 can enter the long-distance office,
113 and 117. Calls originating from a call order table having a set of keys similar to the set of keys shown for the trunk operator in a trunk table may enter the trunk switch train. with keyed impulses which are all qirires through the interurban train of cross-bar switches.



   The remote long distance offices are schematically illustrated by 120, 124 and 128, which receive calls from other long distance calls or from subscribers such as
C, D and E entering local offices 118, 122 and 126 respectively. Subscriber L can initiate a call by transmitting a signal to a local office indicated by 126 and require a connection to be established by a trunk line.



     The call can be registered; the usual way and the subscriber connected to a fee in the long distance office
128 which, in this case can direct the call to the long distance office which is the object of the present realization which; activates the apparatus of the incoming trunk 129. In each case, the drawing indicates that the subscriber has requested a connection with the interurban office. He is illustrated and consequently

  <Desc / Clms Page number 11>

 This trunk lines (1'1 ') (with the same meaning in Fig. 4) are shown between the remote trunk offices 120, 124 and 128, and the incoming trunk junctions 121, 125 and 129 located in this trunk office.



   Examples of three types of trunk lines known herein as interjone junctions are given. like long distance. An incoming trunk trunk coming from a remote trunk office having a set of pulse keys is shown at 1 @ 1.



  An incoming trunk trunk coming from a manual office having trunk equipment with calling on the line and automatic listening for the incoming dialer ("straight forward") is shown in
 EMI11.1
 12. an interjunctio interurbfiinesent.rant8 junction having a junction equipment with ringdown is shown at 129. Each of the above types of junction a ter interurban junctions can be further subdivided or subdivided according to an
 EMI11.2
 number of cr.ll'éJ.ct,: ri, 3 "'Ci <1'.ê8S transmission different "rents.

   A trunk in0r-junctions that can be G.uploy ..; e: for,: 'colll \ 3r a call from a' tLlY'c: i; tt., Long distance praised by uri other long distance office and from there to a third long distance office received the name of
 EMI11.3
 junction-interjunctions, intermediate interurban ("via"). This trunk inter-trunk junction has the highest transmission characteristics that can be had.

   A trunk trunk trunk that runs from one trunk office to another trunk station and terminates there at an associated local office or at a subscriber having access to that office is known as a terminating trunk and does not require the transmission characteristics of the inter-junction

  <Desc / Clms Page number 12>

 
 EMI12.1
 tionsin.t; rur'oainesinte1-iùédiai1-e.

   Some inter-city offices are equipped with '-'. 'A third type of j011Ct'.nïlS-.111ter jOriCt: interurban lOnS having combined transmission characteristics, and which can be used.
 EMI12.2
 ployce either CO "Ui1e junction l.lli: E; l" jO .Ct10115 interurban 7.rlt :: r; ll.: L.LC111 ^ e or C01'1 :: 1C interurban junction dE) tereination. Trunk offices can have trunk trunks of all three species of features extending to another intercity office.
 EMI12.3
 urban.

   The inter-trunk-junctions i, ons-intcr1 = r combined are used whenever an insufficient number of intermediate trunk trunks or terminating trunk trunks are available.

   Since calls from remote long-distance offices entering this inter-urban office may be routed either to another in-
 EMI12.4
 i, E.? "Lil'-.:! ïl or se to1'I :: 1nc1 'in this center;

   interurban, these junctionc intcrjunctions intr.:ru.rbi.1iiCS enter cia.iÂ;> the two trains of ca - :: l, tatc; zr ';., and the co;> .., utat The interurban train and the terminating train cross-barren u1-s are therefore both associated with the incoming trunk junctions 121, 125 and 129.
 EMI12.5
 uo. '.' fie illustrates the 1? ijj. ; ':, the incoming inter-urban inter-junction H.1 is connected to both CO, .1J1Utateur to barr't's ci% ..; 1s; the 203 of the interurban train of COIi'llilL) ttli.E? L1I'S and at the co ': i .utator with crossed bars;: 2; .Ó of the .te1-i.ii- nation of C: vO. : .l: l: tatC.l2 ^.

   Incoming trunks 1: 5 and 129 are connected to switches 1,:. 0 and 113 of the switch termination train and are extended upward (TT ') to be connected to the switches of the intercity train.



   An incoming call signal energizes the switchgear of an incoming trunk trunk which initiates

  <Desc / Clms Page number 13>

 automatically the operation of a coupling such as
500 or 535 to associate the incoming trunk either directly to a free incoming recorder-sender in groups such as 518 or 522 or to a trunk operator position without free cords, such as 531, 532 or
533 with which the recorders-senders are associated
528, 529 and 530.

   Coupling 500 is also employed to select outgoing logger-senders from the recorder-senders groups 510, and 514 which are automatically actuated by an outgoing trunk to transmit pulses to a remote office when needed. An incoming call coming from a key impulse call order table of an interurban key impulse switchboard n 3 automatically activates a coupling to choose a free recorder-sender from groups 518 or 522 which are associated by connectors 543 directly to a marker to set the switches to the appropriate position for placing a call.



   The same applies to incoming calls from remote key-operated long distance offices which automatically direct coupling 500 to choose a free recorder-sender. The logger-senders automatically activate a connector 543, 544 or 546 to associate a marker in order to establish a link.



  In each case, the record is transmitted from the attendant who initiates the call through the coupling 500 to a recorder-sender in groups 518 or 522 to set a number of records to the appropriate position. recorders which record the type of incoming trunk connected to it, and the designation of the office or office and the subscriber to which the call is to be directed. This recording is transferred to the marker to set the switches to the appropriate position in order to establish the link and record it.

  <Desc / Clms Page number 14>

 ment in the recorder-sender constitutes a constant check of the functioning of the marker.

   Incoming calls through incoming long distance trunks from manual long distance offices which can be equipped with trunks with call on the line and automatic listening for the incoming operator or trunk with call on the circuit activate 535 coupling so that calls from manual desks can be routed by the long distance office by a long distance operator without cords. This coupling is automatically controlled by the circuit of the calling incoming junction to indicate the species or category of the calling junction to the equipment associated with the long distance operator position without cords.

   It is associated with a coupling 535 a sequence circuit schematically illustrated by 534 to distribute the incoming calls to the various operators and to find free channels to the operators which are available to handle the incoming calls.



   Couplings 500 and 535 include a small train of cross-bar switches having primary switches connected to the incoming trunk trunks and secondary switches associated with a large number of register-senders or trunk switchboard positions. without cords.

   Coupling control circuits 507 and 542, coupling control connectors 506 and 541, and control jacks 505 and 540 are each separate units which are combined as required to secure free logger-senders of the required type or the attendant position channels without free cords and for controlling the coupling crossbar switches 501, 502, 503, 504 or 536, 537, 538, 539 depending on the link established.

   each incoming junction is

  <Desc / Clms Page number 15>

 connected to the contacts of a primary roised bar switch such as 501 and is also connected to a starting relay in the control relay unit. the start relay is actuated in response to a signal on the calling incoming junction to actuate a free coupling connector such as 506 and obtain employment of a free coupling control unit such as 507,

   chosen from a common group of control units. The coupling control units 507 and 542 fulfilling the same role with respect to a marker to control the linkage and operation of primary and secondary crossbar switches of the coupling to link an inbound trunk to a recorder-sender free or to a long distance operator position without free leads following the category records from the calling incoming trunk.



   After a free recorder-sender has been chosen, or a position without free trunk cords has been chosen and the couplings 500 or 535 crossbar switches actuated to connect the calling incoming trunk to the recorder-sender or at the selected operator position, the control relay unit, connector and coupling control unit are disconnected from the switches. The switches are retained by the recorder-sender apparatus of the cordless operator position for a period of time depending on the functions to be performed and the species or category of the calling incoming trunk. .

   A number of channels are provided in each cordless operator position to which the coupling switches are connected at the rate of one coupling per channel. The common equipment of the operator position without cables can be associated with any channel either automatically in response to a signal on an incoming junction, or according to the operator's wishes.



   A number of 535 coupling switches can

  <Desc / Clms Page number 16>

 be connected to a certain number of position channels at the same time and the position equipment common to these channels can be automatically associated successively with different channels to handle incoming calls or to answer callbacks either on incoming junctions or on outgoing junctions and can be associated manually with any of said coupling links.



   In the event that an incoming call activates the coupling
535, a number of conductors coming from the incoming trunk trunk are connected by coupling to a free lane in a trunkless operator position and a signal is actuated in the trunkless trunk position to indicate that a new call is made. incoming waits to be elapsed. The cordless long distance operator calls the remote long distance operator who transmits the area code or designation of the desired outgoing office or long distance station. The long distance operator without cords then activates the appropriate keys, which excites the recorders of an associated recorder -sender, such as, for example, that the recorder-sender 528 linked to the operator position. long distance without cords 531.

   In addition, category signals are transmitted directly from the incoming trunk trunk to the sender-register to record in the sender-register the species of the incoming caller trunk.
 EMI16.1
  <.ix; t1-e; nents de ns l 'enre; ist1- <.ur-envo;.; eui activates the device used to choose a free connector between the recorder-sender and a free marker. The office is
 EMI16.2
 d; equipped with a certain nOl1bro dr- y, flr ;;:> e1 = rs, so that an i:;. n1-.w.; i: r li.'ore is norr:; aler1pnt available for flow all calls come in.

  <Desc / Clms Page number 17>

 



   A trunk office can be equipped with several markers of a single type known as (the combined trunk and termination marker. This type of marker is designed to establish inbound trunk links with a remote trunk office, an office located in the air of the interurban center or of the service switchboards and service junctions Other offices:

  ', interurban can be fitted with separate markers comprising several markers for terminating calls to remote toll offices, service switchboards and service trunks, and several other markers for terminating calls ending in 1. from the interurban center and to service switchboards and service junctions. The two types of markers have been illustrated schematically.

   The 0 to 1 markers numbered 640 and 624 can be either combined long distance and termination markers, or long distance only markers. schematically shown at 625 is a termination marker which would be deployed in a toll office when the 0 to 1 markers are used to terminate calls to remote toll offices only.



   For this description, it will be assumed that the marker 0 was free and chosen by a connector such as 543, 544 or 545 and associated with the recorder-sender 528 in the trunkless position 531.

   The marker recorders shown in the detailed representation are activated by the recordings made by the operator.
 EMI17.1
 without cords in 1 t C'T? r E?; ¯'iStrCLlr-eriVU ,, rPLlr and E are under the command: .the associated anre @ istreur to establish the link.

   These records control various operations in the marker including routing the call to an outgoing trunk, free in a group of outgoing trunks.

  <Desc / Clms Page number 18>

 tending to a particular long distance office or a free outgoing switching junction for connection to an office located in the toll counter area.

   Assume, for example, that a recording has been made to connect an incoming trunk trunk from a remote trunk office to an outbound trunk trunk extending to another remote trunk office. there is thus an artery or road relay in the marker,

   which will bring about the selection of a free outgoing junction extending to that particular office by associating the marker with a group of terminals with which these outgoing junctions are associated. These loggers can cause the operation of a single route relay or the triggering of a number of route relays and the activation of a connector such as 740 or 741, to associate the margetear with the monitoring relays. special terminal blocks
 EMI18.1
 centers f, ch0r, latiquorate in 707 c '.'.

   71,) connected to, <q1-ounc or to grcuoes of outgoing trunks extending to an office, for which the call is recorded. When a free outgoing trunk to a particular office is available, signals inform the brand, which continues the successive operations to establish the connection.



   Any kind of incoming trunk trunk, tandem trunk or trunk coming from service operators entering the office can be linked to any kind of outgoing trunk. In view of the many characteristics of the different junctions and in view of the number of groups and subgroups in which these junctions must necessarily be arranged there must be transmitted to the marker from various sources a considerable number of indications to guide the marker in the establishment of a link of an incoming trunk of a
 EMI18.2
 special species

  conl: cct,; (''; a, -; O! "reads ['tr> 11r u bars

  <Desc / Clms Page number 19>

 crossed mounted on a particular arrival frame, of even (L) or odd (0) name, with an outgoing junction of species
 EMI19.1
 identical or to ii ', i,' éihi-11.1e connected <i a crossbar L switch mounted on a particular output frame (the even or odd number.



   ..due to the complexity of a long distance system and the flexibility; required, no permanent link is established between the marker and the crossbar switches.

   Rack connector units are used to connect a large number of incoming secondary cross-bar switches, such as 202, and output primary cross-bar switches, such as 300, to the marker to establish gauge runs. circuit massaging via junction conductors or junctors between a primary feed crossbar switch, such as 200, to which is connected an incoming calling junction and a secondary output crossbar switch,

   such as 301, to which a free outgoing junction is connected. However, these rack connector units are chosen by the marker according to the location of the inbound and outbound trunk switches after the location of these switches has been indicated to the marker.

   The incoming trunk primary crossbar switch, such as 200, is associated with the marker by the calling incoming trunk, a tie switch, such as 500 or 535, and a trunk assignment connector, such as 543, which with the exception of the incoming trunk does not bear a designated or numerical relation to the incoming terminal switch or to the frame on which this crossbar switch is mounted. These equipment units can be used for calls originating from several different inbound trunks connected to incoming primary switches located at various locations.

   This is also true of the com-

  <Desc / Clms Page number 20>

 secondary cross-bar switch of outgoing junctions, such as 301, which is associated with the marker by the outfitting of the outgoing junction of the branch jacks which are employed to obtain flexibility in the arrangement of groups of junctions, junction group relays, such as 707 to 716, and connectors such as 740 and 741. (Note in fig. 7 that LT marks the last junction of a group, FT the first junction of a group. The SM wire goes to a selector magnet).



  Since there is no link between the primary incoming or secondary outgoing switches and the marker other than selectable equipment units that are common to different switch racks, a control system Multiple frequency signaling is included in this trunk system to transmit signals to the marker providing the location of switches connected to selected inbound and outbound junctions for a telephone link and to let it know whether they are mounted on odd or even racks. This signaling system is associated with the marker by the incoming primary cross-bar switch, the apparatus of the calling incoming junction and then by the circuits established by the equipment units chosen to connect the junction to the marker.

   The signaling system is also connected by the output secondary cross-bar switch associated with the freely chosen outgoing junction, to the marker, by circuits established through the intermediary of equipment units chosen to connect. this outgoing junction to the marker. In this signaling system, electric currents of different frequencies are variously combined to obtain a large number of different signals equivalent to the large number of switch racks in the toll office.

   The system

  <Desc / Clms Page number 21>

 signaling is also used to let the marker know that the junctions of the group being tested are all occupied and that a group of junctions has been added to this normal group of junctions and that the added group can be found on a different frame than the one on which the normal junctions are located. In this case, the signaling system causes an adjustment of the apparatus of the marker to associate the marker with the added group of junctions. If a free junction is chosen, in the last group, a multi-frequency signal is automatically transmitted to the marker which gives the situation of the switch connected to the chosen free junction.



   A system for sending signals at multiple frequencies is associated with the selection electromagnets of the primary incoming switches and the secondary output switches. Signals are transmitted as a combined frequency on a single conductor which is later used to actuate the selector electromagnets (SM) as previously explained, this signaling system extends throughout the communication system long distance and therefore the possibility of transmitting the signals on a single conductor is a great saving.

   The organization of the signal transmission apparatus, as shown in Fig. 8, comprises several generators or other current sources each having an amplifier system and it is associated with each of those. here are a number of resistors to distribute the load of the generator and facilitate the connection of the combinations of frequencies to transformers associated with each frame of cross-bar switches.



  Three frequencies are combined for each frame number signal. For example, transformers 800 to 801 include a large number of transformers associated with crossbar switches of a rack. The primary windings of these transformers are connected to the -21-

  <Desc / Clms Page number 22>

 frequency generator 840, to frequency generator 841, and to frequency generator 842 through their respective amplifier circuits, each generator transmitting current of a different frequency. The secondary windings of transformers 800 to 801 are each connected to the windings selector electromagnets on this frame. Transformers 810 to 811 are used to transmit a different combination of frequencies.

   these to the selector electromagnets of another frame. The selector electromagnet 201 associated with the primary crossbar switch 200 located on a particular frame is connected to the multiple frequency signaling system through conductor 218 which can be traced to the secondary winding of transformer 810. A combination of frequencies is transmitted by transformer 810 from generator 840, generator 841 and generator 843. Since transformers 810 to 811 which can represent ten transformers are associated with a particular frame, the secondary windings of this transformer are connected by the windings of the selector electromagnets of this particular frame.

   The combination of frequencies thus transmitted to the secondary winding of the transformer 810 extends through the winding of the electromagnet 201, then through the incoming junction which is connected to the crossbar switch 200, thence through the conductor 130. and the contacts of the cross-bar switches of coupling 535, the sequence circuit 534, the switchgear of the trunkless position without leads such as 531 and an associated sending recorder such as 528, by the contacts of the multiple contact relays. of connector 543, then the marker and the contact of the normal relay 622, the normal relay 620, the relay 619 which is actuated at the primary winding of the transformer 617.

  <Desc / Clms Page number 23>

 



   The combination of three frequencies is thus transmitted to the receiver system of the marker shown in the upper part of FIG. 6. The receiver system comprises: a number of filters 600-604 each allowing a particular frequency band to pass, for example the filter 600 passing the frequency generated by the generator 840 as transmitted, by the amplifier which is associated with it. Each receiving unit in the receiving system has a tuned transformer 605 to 607 which is operated by a particular frequency. The transmitted frequency energizes the tube, such as 608, 609 or 610, which creates a plate current to actuate a relay such as 611, 612 or 613.

   Since the frequencies transmitted by the selector solenoid 201 came from the generators 840, 841 and 843, the currents of different frequencies pass through the filters 600, 601 and 603, to actuate the tuned transformers 605,606 and a tuned transformer associated with the fourth filter 603. Relays 611, 612, and a relay associated with filter 603 are actuated to establish a locator signal circuit. Each relay of the receiving units is associated with another relay comprising a large number of contacts such as 614, 615 and 616. Given the large number of contacts on these relays, they could not be actuated directly by the plate current. tubes in each receiving unit.

   In operation, the three relays, such as 614, 615 and a relay actuated by current flowing through filter 603, establish a special series circuit for actuating the marker apparatus comprising a relay such as 633, which corresponds to the number of the rack on which the selector electromagnetic 201 and switch 200 are located. There is one rack relay, such as 633, for each incoming rack in the office. At the time specific to the reception of the signals indicating the frame number of the incoming switch on which

  <Desc / Clms Page number 24>

 the calling inbound junction is located, the inbound frame breaker relay 630 is actuated by the marker to close a circuit path for the frame relays.

   The circuit for actuating relay 633 is however established by the combination of the transmitted frequencies.



  This combination of relays 614, 615 to 616 actuated by the combination of frequencies also establishes a circuit to indicate whether the frame on which the junction is located is an even (0) or odd (E) frame and accordingly actuates the switchgear of the marker to adjust the latter so that it is correctly connected to a coupling such as 209 associated with the appropriate arrival frame. The number of the function group and of the junction are also supplied by signals given to the marker and the situation of the switch is thus effectively identified.



   When a free outgoing junction to a designated office has been located, circuits are energized to indicate the rack number on which that free outgoing junction is located. The outgoing junctions of the various groups are connected to the local allocation or termination frame or to the branch jacks by the device known as the trunking allocation frame, shown in the left part of Fig% 7. Trunking trunks are very expensive and the number of trunks extending between offices is kept within limits that will accommodate the maximum normal communications traffic.

   The branch jacks are provided to allow flexibility in rearranging the grouping of junctions in special cases and to easily add junctions to a group when for any unforeseen reasons they are needed. These junctions can be added directly to the normal group of office junctions or can be managed through the inter-

  <Desc / Clms Page number 25>

 mediator from other intermediate centers to the office requiring the added connections. Each outgoing junction is connected by two conductors such as 744 and 745 to the branch jack associated with it so that the junction can be tested for its state of freedom or occupation and to control the operations of the marker.



  A third conductor 318 is extended from the connecting jack to the selector electromagnet associated with the secondary crossbar switch connected to this junction. It will be assumed that the free junction found is connected to the crossbar switch 301 and that the selector electromagnet 302 is used to operate this switch.



  This selector electromagnet is connected to the secondary winding of the transformer 800 of the frequency generator circuit via the conductor 320. The transformers 800 to 801 are associated with the frame on which the crossbar switch and the selector electromagnet are mounted.



   Three frequencies are thus transmitted from the generators 840, 841 and 842 by the intermediary of the amplifiers and resistors which are associated with them and which are connected to the primary of the transformers 800 and 801. This causes the transmission of the three currents of the secondary of the transformer 800. , by the winding of the selector electromagnet 302, the conductor 318, the contacts of the branch jack 720, a multi-contact junction group relay shown schematically at 707 and the allocation connector. bution of interurban junctions 704 to the marker. While preparing to receive the signal, the marker actuated relay 620, relay 619, and output frame contactor relay 631.

   The multiple-frequency signaling combination is thus transmitted by the right-hand contact of relay 622, the normal contact of relay 620, the contact of relay 619, to the primary winding of the transformer.

  <Desc / Clms Page number 26>

 617. In this case, frequencies are passed through filters 600,601 and 602 to energize the associated matched transformers 605,606 and a transformer connected to filter 602, which current is amplified to energize associated tubes such as 608, 609 and a tube in circuit with the filter 602. In response to the transmission of these three frequencies the first three relays, such as 611 are actuated to actuate the first three relays, such as 614, 615 and a third relay.

   By operating the last three relays establish a series circuit by their contact and by a particular contact of the outgoing junction frame contact relay 631 to energize a particular frame relay such as 634 in order to arrange the circuits of the marker in order to the connection with a frame on which the free outgoing junction had been found. The combination of relay contacts, such as 614 is also such as to tell the marker whether this frame is an even or odd frame.



  The marker is therefore given the number of the frame on which the calling incoming junction is located and the number of the frame on which the free outgoing junction is located extending towards a particular office.



   Considering the number of cross-bar switch racks in an office, one can see how many different connection combinations are required. For example the calling incoming junction can be any junction in any group of one of the even or odd frames, and a path must be found through the crossbar switches to a free outgoing junction to any office that includes switches on all sortia mounts.

   Combinations of incoming secondary and output primary crossbar switches must be operated to connect the connecting conductors.

  <Desc / Clms Page number 27>

 switching and signaling between any incoming primary crossbar switches and any secondary output switches. Secondary incoming switches, such as 202,205 and 208 and primary outgoing switches, such as 300,303 and 306 are used for these connections. Free jumper conductors must also be found between incoming secondary switches and output primary switches to establish this connection.

   The marker is thus guided by the multi-frequency signaling combinations to associate with particular rack connectors such as 209, 210, 309,310, in order to reach racks comprising switches to be used to make connections in response. to the records transmitted to the marker. Connectors of this kind are associated with all office frames and the drawing shows them schematically associated with the inbound termination frame, outbound termination frame, inbound trunk frame, and outbound trunk frame.

   If the calling arrival junction is on an even frame, a connector such as 210 associated with that frame is energized by the marker and circuits are established between the marker and the crossbar switches by a known path. under the name of local channel, represented by the conductor 214. It can be made use in certain cases of a second path going from the same marker to the same switches by the circuit 212 passing through the corresponding channel of the connector if the channel corresponding in the connector of the odd-numbered frame is entered. The circumstances in which this arrangement is used are discussed in the context of the detailed description.



   If the outgoing junction had been found on an odd frame, a connector 310 associated with this frame would have been normal.

  <Desc / Clms Page number 28>

 incorrectly operated. The circuit route through this connector would pass through conductor 316 which would again be called the local channel. In some cases, however, this frame can be reached through the even connector and the circuit lead 311 when the corresponding channel is used.

   The operation of the incoming and outgoing connector circuits in combination with the marker, controls the selection of secondary incoming crossbar switches and primary output crossbar switches as well as a set of junction conductors through the link frame 217 to associate the incoming junction on the primary crossbar switch with the outgoing junction on the secondary output crossbar switch. This connection is established when secondary incoming and primary output cross-bar switches as well as a set of connecting conductors between. these have been tried and found free.



   In the trunk grouping organization for an urban office, sufficient space is provided on both the switch frames and the trunk relay frames for possible expansion of the trunk groups. However, when rapid changes occur in a particular neighborhood due to unexpected circumstances, a larger group of junctions may be required than previously assumed. In certain cases, a place cannot be found for such an enlargement of the group of junctions on the frame supporting the normal group of junctions. In this case, an additional group of junctions is located on a different frame.

   This flexibility is an advantage of a trunk system, but requires sending a large number of multi-frequency signal indications to the marker for the group, from junctions extending

  <Desc / Clms Page number 29>

 to that particular long distance office. Devices are provided in the multi-frequency signaling system to accommodate this flexibility.

   When the marker has tried the junctions of a normal group extending to a particular office, and finds that all the junctions were busy and that an additional group of junctions was available, he is notified when he tries. the last normal group join. In this case, the last junction of the group pretends to be free and the marker apparatus is accordingly actuated to try to grab the junction, but instead of finding a free junction, it grabs a group to try it. full of junctions. The apparatus used for this arrangement is shown in the right part of FIG. 7.

   Jack 721 represents the last junction of a normal group and is connected by a patch cord 748 to an adjunct group of junctions known as the hop-scan junction group, since it can be on a frame different from that on which the normal group of junctions is located. The unoccupied state of a junction is ordinarily revealed to the marker by a battery running from the outgoing junction to the test lead in the marker.



  This can also be indicated by an open circuit.



  If an outgoing junction is occupied, the earth is associated with this conductor. This state of affairs can be observed by referring to FIG. 16 of the detailed drawing.



  There is a circuit state between the normal group of outgoing junctions and the skipping group of outgoing junctions, which varies depending on whether these junctions are occupied or free. A free outgoing junction in the group of jump scanned junctions is shown schematically at 727. This shows the battery associated with a test lead extending to the marker, and the earth.

  <Desc / Clms Page number 30>

 connected to the occupancy conductor of the group by the winding of relay 724. As long as there are free junctions in the group with exploration by assistant jump of junctions, this earth is extended from all free outgoing junctions by the Winding of relay 724 to the battery which activates relay 724, connecting earth through the winding of relay 723 to the socket of jack 722.

   A similar state of affairs exists in the normal group of junctions, since a ground is connected from all free junctions to a conductor, such as 744, from the free junction and extends through the branch jacks to the winding a relay in the overflow or discharge junction, such as 725. When there are free junctions in the normal group, a circuit is therefore established from earth to all socket conductors connection jacks in the normal group. Since the jump jumper assistant exploration group is connected to the last normal junction, this ground is extended from the free junctions in the normal group by the socket of the branch cord 748, the socket of the exploration jack by jump 722, the winding of relay 723 to earth on the contact of relay 724.

   For this reason, an earth coming from free junctions in the normal group bypasses relay 723 and will not allow this relay to operate. This also places a busy earth on the group to be explored by jumping from the rear contact of relay 723 through the neck conductor and the connection cord to the marker, as an indication to verify that there are free junctions in the terminal. normal join group and the marker made an error in trying to enter the exploration group by assistant jump.



   When all outgoing junctions in the normal group are occupied, the earth is removed from the conductor

  <Desc / Clms Page number 31>

 test of all the junctions in this group and at this point a circuit is established to actuate relay 723, comprising: earth, relay contact 724, relay winding 723, jack socket 724 , the socket of the connection cord 748, the winding of the relay 725 and the battery. The junction jump scan group is therefore available for selection) and a multi-frequency signal is transmitted to the marker to re-tune the marker accordingly. The arrangement of transformer 730 is similar to that which has been described previously for transmitting a signal by the selector electromagnet.

   In this case, a special frequency is transmitted from generators 841, 842 and 844 through the primary winding of transformer 730 and from the secondary winding through the winding of relay 726, the neck conductor of jack 722, the nape of the patch cord, with the nape of jack 722 representing the last jump scan junction of the normal group, thence to transformer 617 in the marker. Transmitting this combination of frequencies operates three relays, such as 614, establishing a series circuit to actuate the jump-search contactor relay 632, releasing the contactor relay from outgoing junction 631 and establishing a circuit. to control multi-frequency relay 726.

   After this has been done, the combination of three relays, such as 614 is released and a second combination of frequencies is transmitted to establish a circuit in the marker so as to actuate a particular route relay used to reach the group at. exploration by adjunct jump of junctions. This combination of frequencies is transmitted from three generators, following the desk over which the junctions extend. An example is given where the combination is transmitted from the generators 840, 841 and 844 through the lower contact of the

  <Desc / Clms Page number 32>

 relay 726 and the primary winding of transformer 730 with a path to the marker, which is the same as previously described ending in transformer 617.

   The relays 614, 615 and 616 are now actuated to establish a circuit through a contact of the contact breaker relay 632 to actuate the particular road relay controlling the test of the assistant junction group.



  Testing of the outgoing junctions in the jump junction scanning group now continues in the usual manner and the hop scanning apparatus including relay 632 is released to allow this normal sequence of operations. The output frame contact relay 631 is again actuated to establish a path through which a multi-frequency signal can be transmitted, notifying the frame on which the auxiliary junction group is located.

   When a free junction is found in the junction hop scanning group, this multiple frequency signal is transmitted by the selector electromagnet associated with the switch connected to a free outgoing junction in the same way as previously described for the transmission of a signal for a frame number giving the situation of a free junction in a normal group.



   When a free junction has been located in an assistant-hop exploration group, and when the number of the frame on which the junction is located has been transmitted to the marker, the operations take place as previously described to control the operation of one of the rack connectors 209,210, 309,310, 229, 230, 339,340, depending on whether the call is an intermediate long distance call directed to a remote long distance office or a terminating long distance call directed to the office located in the area from the interurban center. This causes the se-

  <Desc / Clms Page number 33>

 Selecting a secondary incoming switch, a primary outgoing switch, and a trunk conductor path between these switches to connect the calling incoming trunk to the chosen free outgoing trunk to a particular office.



   If the service of an outgoing logger-sender is required at this time, that outgoing logger-sender is automatically connected to the outgoing junction by energizing a coupling such as 500 operated by the outgoing junction circuit. For example, if the outgoing trunk extends to an office requiring dial pulses or key pulses, these are transmitted from an outgoing logger-sender such as 510 or 514. Outgoing logger-senders are shown. in Fig. 5 next to the coupling which serves both the incoming and outgoing recorder-senders.

   A circuit can be followed from these logger-senders by the switches to the outgoing trunk circuits. Therefore, after the link between the incoming and outgoing switches of Figs. 2 and 3 has been established, pulses can be transmitted from an incoming recorder-sender by a coupling, such as 500, of the switch train, Figs. 2 and 3, by the same coupling or another coupling to the outgoing recorder-sender, to put the registers of the outgoing recorder-sender, the incoming recorder-sender, in the appropriate position having been previously set to the appropriate position either by the operator initiating the call or by the operator without cords.

   As soon as the recorders of the output recorder-sender are set to the position, i.e. adjusted according to the position of the incoming recorder-transmitter, the pulses are transmitted directly by the conductors of the outgoing junction either to a remote long distance office or to a

  <Desc / Clms Page number 34>

 termination office, such as 407, 409 or 412 depending on the call designation.



   Incoming calls from manual long distance offices with call on the line and automatic listening of the incoming operator or from offices with call to the circuit are routed by the interurban operator without position cables. 528,529 or 530.



  In this case, the code of the remote office is recorded on the keypad of the long distance position without cords to control the recorder-sender associated therewith and a marker. When the crossbar switches have been set to the position and a link has been established to a remote attendant, the cordless attendant can transmit the calling designation to the remote attendant or the calling designation can be given to the remote operator by the operator who initiates the call as soon as the link has been established by this interurban office and the called operator has been obtained.



   Detailed description.



   ----------------------
It will be assumed that a long distance call is initiated by subscriber A, FIG. 21, which calls the operator of the local subscriber office 2100 and informs her of the destination of a long distance call., The operator of the subscriber establishes a communication with the manual long distance office 2104 through the junction 2102 of the usual way by associating plug 2140 to jack 2101 and plug 2141 to jack 2103.



  The equipment can be of a well known type and does not require description in this disclosure. The long distance designation is registered by the long distance dialer in the long distance office 2104 who continues to establish the desired connection by initiating a call on a long distance interjunction from this remote office represented by conductors 2150 and 2151. For convenience,

  <Desc / Clms Page number 35>

 As described above, it has been assumed that there is a trunk-to-trunk trunk junction on the circuit between the remote trunk office 2104 and the inbound trunk call on the circuit shown in Figs.



  12 and 13 of the intercity office with cross-feed switches. The call may have been initiated by subscriber B or C and a long distance call may have been established by an automatic long distance office 2110 or an interurban office with junction with call on the line and automatic listening to the line. the incoming operator 2124. An incoming call from trunk office 2110 through an incoming pulse junction would enter the toll cross-bar switched office into an incoming trunk arranged for that link, which would automatically direct the call by a coupling to a key pulse recorder-sender such as 2214 shown in FIG. 22.

   A call from an office such as 2124 using trunks known as trunk trunks with call on the line and automatic listening to the incoming operator would enter the long distance office with crossbar switches. in an incoming inter-city trunk arranged to receive signals of this kind from a remote trunk office. This signal will be transmitted to the junction with call on the line and automatic listening of the incoming operator by the association of the battery and the earth to the junction conductors, at the far end. of the junction.

   Calls passing through tandem trunks are of the same species, either by transmitting signals by pulses or by initiating a call by a battery signal and then establishing the link by means of instructions from an operator to the other. As in-

  <Desc / Clms Page number 36>

 indicated on the drawings, all calls passing through inter-trunk junctions with call on the circuit or with call on the line and automatic listening of the incoming operator are linked by a coupling to the operator position without cords.

   The trunk office 2104 link with the inbound trunk calling shown in Figs. 12 and 13 is initiated by the application of inrush current to junction conductors 2150 and 2151, which energizes relay 1201 in the circuit of the incoming trunk trunk. A circuit is normally established by the relay 1201 from the earth by the winding of the relay 1202, which keeps the relay 1202 activated, and for this reason the excitation of the relay 1201 by the transmission of the aforementioned call signal triggers the relay 1202 to establish circuits to associate this incoming junction with the equipment of the inter-city office with cross-bar switches to establish a communication between this junction and a desired outgoing junction.

   As previously established, trunk trunk inter-trunk junctions have transmission characteristics which vary according to their use. For the example of connection from subscriber A given, it can be assumed that the calling incoming trunk trunk has the highest transmission characteristics and that the connection should be made through the trunk train of switches with a trunk outbound extending to another remote long distance office.

   This constitutes an intermediary link and requires the use of trunk trunks with the highest transmission characteristics, both from the home office to the trunk switch office with cross-bar switches.

  <Desc / Clms Page number 37>

 and from the cross-bar switch toll office to another remote toll office, with which a call has been requested. In response to the operation of relay 1201 and the trip of relay 1202, a circuit is established comprising: earth, contact 6 of relay 1307, contact 5 of relay 1220, contact 2 of relay 1202, winding of relay 1304 and battery, which operates relay 1304.

   Relay 1304 establishes for itself a blocking circuit comprising its contact 3, contact 5 of relay 1220, contact 6 of relay 1307 and earth connected to the armature of relay 1202 and by contact 9 of relay 1301 to conductor 3228 which is used later for testing purposes from the position circuit as well as for establishing a holding circuit for the switching electromagnets of the cross-bar switches of the intercity train of switches shown in Figs. 14 and 15. A circuit is also established by the windings of relay 1322 and the contacts of relay 1304, which is inactive at this time, since the windings of this relay are arranged to oppose each other. 'other.



   When the call period has ended, relay 1201 returns to the normal position and re-establishes an operating circuit for relay 1202 and the following operations occur, in order to associate a coupling control circuit with the incoming junction In the circuit previously followed to block relay 1304 it was shown that the earth is connected to armature 2 of relay 1202. The repeated operation of relay 1202 transfers the earth from the external contact to the internal contact, which establishes an operating circuit for the relay 1213 by the contact 5 of the relay 1212. The relay 1213 establishes for itself a blocking circuit by the contact 5 of the relay 1301, which blocking circuit remains

  <Desc / Clms Page number 38>

 under the control of relay 1301.

   In operation, relay 1213 connects certain conductors to the coupling relay to control the selection of the coupling comprising a circuit for the coupling on relay 4311. When operating, this on relay causes the selection of a connector of FIG. 42 to associate the incoming junction with a coupling control circuit. (Note that in Fig. 42, the wires marked W4207 go to the windings of other connector relays 4206, the wires marked C4207 go to the contact of other such relays, and wires marked LKC go to other coupling control circuits).

   There are several selectable coupling control circuits which may be temporarily associated with an incoming trunk or an outgoing trunk to choose circuit routes passing through the coupling switches as shown in Figs. 22 and 32, with a view to connecting an incoming junction either to an incoming recorder-sender of FIG. 22, or to an operator position channel without cords of FIG. 55, or to connect an outgoing trunk to an outgoing recorder-sender of FIG. 22. This control circuit shown in Figs. 52-54 and 62-64 stores the category and characteristics of the calling incoming trunk and establishes the link through the cross-bar coupling switches.

   Since there are many species of incoming junctions, the coupling control circuit functioning as a recorder and marker must in any case be operated in a manner which depends on the category of the junction connected to it.



   As previously established, the relay 1213 associated, while functioning, the earth to the starting conductor 4300 in a circuit comprising: the earth, the contact 1 of the relay 1214, the contact 3 of the relay 1213, the contact 1 of the relay 1212, the conductor 4300, the contact 1 of the relay 4310, the winding of the start relay 4311 and

  <Desc / Clms Page number 39>

 battery . While operating, relay 4311 establishes the turn-on circuits to select a coupling and control the connection of the cross-bar coupling switches shown in FIG. 32 between the circuit of the junction with call followed by the incoming circuit (Figs. 12 and 13) and one of the switchboard circuits without leads among a number of these as shown in Figs.



  55,56, 65,66, 71 and 72 as follows. First, a circuit is established to operate the nn of relays 4201 xx or 4202. This circuit includes: battery 4312, resistor 4313, contact 1 of relay 4311, contact 3 of relay 4315, contact of relay 4316, coil of relay 4201, contact 1 of relay 4202, and earth . A second circuit is established to operate the time relay 4317 from earth, through contact 3 of relay 4311. A third circuit is established from earth, through contact 2 of relay 4311 to contact 27 relay 4206 to be used when the latter relay is actuated. While operating, relay 4201 establishes a circuit for relay 4205 which in turn establishes an obvious circuit for relay 4206.

   In operation, relay 4201 also establishes a circuit for one of chain relays 4209, 4210 or 4211 which are actuated in succession when free mating connectors are chosen and become occupied. In this example, the drawing shows the circuit arranged to actuate relay 4209 from the battery through contact 4 of relay 1201, contact 1 of relay 4212, the winding of relay 4209, the relay chain to earth, on contact 2 of relay 4211. The coupling connector associated with relay 4209 is thus taken to be used.



   The coupling system described in this application constitutes an arrangement of apparatus making it possible to obtain connections between a large number of trunk lines.

  <Desc / Clms Page number 40>

 or tandem known here as junctions, and a large number of recorder-senders or cordless position circuits with a minimal amount of devices.



  Therefore, the coupling system is divided into separate sections or units, which creates a large number of choices for the connection of any trunk or tandem interjunction trunk with free logger-senders or positions without cables. free.



  The crossbar switches shown in Fig. 22 show the arrangement of interconnecting trunk trunks with free inbound register-senders which may be of different species depending on the species of inbound trunk used for the link.

   The crossbar switches of Fig. 22 are associated with the remainder of the coupling, as shown in Figs. 42, 43, 52, 53, 54, 62, 63 and 64 and with the register-senders in the same way as the crossbar switches of FIG. 32 are connected to the positions without cables. The cross-bar coupling switches of FIG. 32 are used in the interconnection of interurban junctions-interjunctions coming from manual offices such as for example, as junctions with incoming call on the circuit, junctions with call on the line and automatic listening of the attendant incoming or tandem junctions extending to operator positions without cords.

   It is clear that long distance trunks coming from manual toll offices require the services of an operator in the toll trunk office with cross bar switches, while inbound long distance trunks from processed long distance offices. based on pulse signals only requires the service of an arrival recorder-sender, as shown in Fig. 22. The contact relay

  <Desc / Clms Page number 41>

 Multiple 4206 and the relays shown in the upper part of Fig. 42 constitute an arrangement for giving an incoming junction several choices in obtaining the services of a coupling control circuit. There are several 4314 relays for each group of incoming junctions.

   These different relays 4314 are connected to several relays 4206 which are interconnected when jumpered as shown, so that a choice of relays is available when a particular relay is found busy. Relay 4207 and the armatures of relay 4206 constitute a connector between groups of junction circuits and the coupling control circuit. There are in each connector a number of relays 4207 equal to the number of control circuits. There are for each connector a number of relays such as 4206 equal to the groups of junctions entering the right contacts of relay 4314.



   From the above, it can be seen that for each trunk trunking entering the office there is a choice of a number of circuit routes to obtain the services of a free coupling control circuit (Fig. 52, 53, 54, 62, 63, 64) and that there are several choices between the trunk circuit and recorder-senders or positions without leads, since there are a number of different paths going through the switches with crossed bars to recorders-senders or to positions without free equivalent leads. The foregoing arrangement makes it possible to have numerous routes to the more expensive groups of apparatuses, such as for example the coupling control circuit, and thus to limit the number of control circuits.

   This coupling control circuit can be compared to a marker to control the coupling switches in much the same way as the main marker of the crossbar system.

  <Desc / Clms Page number 42>

 controls switches arranged to connect an incoming junction to an outgoing junction.



   In the present example, it is assumed that the control circuit associated with relay 4207 is free since relay 4209 was actuated. In operation, relay 4209 establishes an obvious circuit to actuate relay 4207 which connects a coupling control circuit through its contacts and the contacts of relay 4206 to the left contacts of relay 4314 which has not yet been actuated.



  In operation, relay 4207 establishes an obvious circuit to actuate relay 4208 and extends ground through conductors 4240, 4221 and 4222 to the control circuit. The circuit established by conductor 4220 energizes relay 5402. The circuit established by conductor 4221 operates relay 5201. The circuit passing through conductor 4222 establishes a blocking circuit for relay 5203, which is used later after this relay has been actuated. While operating, relay 5201 closes a circuit to operate relays 4213 and 4214, which includes: the battery, their upper windings, the three conductors represented by conductor 5252, contacts 1, 2 and 3 of relay 5201, and earth .

   Ground is also connected to the top winding of relay 4212, but the operating circuit of this relay is shunted by ground from contact 1 of relay 4207, which prevents relay 4212 from functioning. This indicates that all the paths passing through this connector are occupied. The circuit for relay 4208 is established either by the operation of relay 4206 or 4207 and the busy state of the coupling is therefore maintained until both relays have tripped. Relay 4208 establishes a blocking circuit for relays 4213 and 4214 through contact 1, and a circuit for time relay 4320 which

  <Desc / Clms Page number 43>

 can be established when relay 4205 trips if relays 4207 and 4208 have not tripped.

   In operation, relay 5402 establishes an obvious operating circuit for relay 6404 and an operating circuit for relay 5209 which includes: battery, resistor
5412, contact 4 of relay 5402, contact 5 of relay
5403, relay contact 3 5309, relay contact 4
5410, the coil of relay 5209 and the contact of relay 5301 and earth. Relay 5209 is blocked to earth on its contact 3.



   A particular control circuit such as represented by FIGS. 52,53, 54, 62, 63, 64 has now been entered to control the selection of crossbar switches available as shown in FIG. 32 to re-establish a link between the circuit of the calling incoming trunk (Fig. 12 and 13) and a position channel.



  By operating the relay 6404 prepares a test circuit, as explained later, and applies a no-function test to the test relay 6405. It can be explained here that a test of the circuits is carried out gradually as the circuit command works. If relay 6405 operates during the bump test, operation of the control circuit will be blocked by the operation of relay 6402. For this description, it will be assumed that relay 6405 has responded correctly to the bump test and therefore did not work.



  At this time or previously, relay 6213 is operating in a circuit comprising: the battery, its winding, contact 1 of relay 6305, conductor 4247, contact of relay 4207, contact 27 of relay 4206, contact 2 of relay switch 4311 and earth. Contact 6 of relay 4207 represents a large number of contacts as shown on relay 4206. There are several relays, such as 6213 or 6209 corresponding to the subgroups of

  <Desc / Clms Page number 44>

 Calling incoming trunks in a large trunk group, and one of these relays is now actuated to identify the subgroup of trunks that contains the calling trunk.

   It can be assumed that relay 6213 corresponds to the subgroup of the calling incoming trunk in use for the connection described here. In operation, relay 6213 establishes a blocking circuit to its operating ground through conductor 4247 and also establishes an operating circuit for relay 6210 through its contact 1 and conductor 4247 to ground. Upon operation, relay 6210 establishes a circuit for relay 6305 which is obvious. Relay 6305 locks to earth on contact 5 of relay 6213 and opens the operating circuit of relay 6213 which is now held in the actuated position by its blocking circuit.

   Relay 6305 also establishes a circuit to actuate relay 4314, which circuit includes: battery, contact 4 of relay 6305, contact 2 of relay 5204, circuit 3 of relay 6203, contact 1 of relay 6210, Subgroup Relay 6213 Contact 4, Conductor 4245, Relay Contact 4207, Relay Contact 25 4206, Relay Winding 4314, and Ground. In operation, relay 4314 now associates the conductors coming from the primary coupling switches and calling incoming junctions into a particular subgroup through contacts 2 to 15 of relay 4206 and an equivalent number of contacts from relay 4207 to the control circuit. coupling.



   Selection of the interurban junction.



   -------------------------------------
It may be indicated at this point that the contacts of relay 4314 are associated with a number of junctions (usually ten) represented by conductors 4300 and 4309. There is, however, a common turn-on circuit for the junctions of this. subgroup passing through contacts

  <Desc / Clms Page number 45>

 of relay 4310 and after input from the control circuit the calling junction must be identified in order to be released. The conductors extending from these junctions through contacts 7 and 8, which may represent ten junctions are extended by the contacts 7 and 8 of relay 4206 and similar contacts of relay 4207,

   then by conductors 4228 and 4229 to the ten relays 5206 to 6210 of the control circuit.It was assumed in this case that the junction with call on the circuit (Figs. 12 and 13) is associated with conductor 4300 connected to the junction zero of the group. A ground was associated with conductor 4300 by the junction with call on the circuit to actuate the start relay 4311. This earth is now extended by contact 7 of relay 4314 and contacts 7 of relays 4206 and 4207, conductor 4228 , contact 4 of relay 5211 and the winding of relay 5210 to the battery.

   Relay 5210 operates and is blocked by its contact 4 to conductor 4228. This same earth conductor 4300 extends through the contacts of relay 4310, contact 8 of relay 4314 and all similar contacts associated with the set of several junctions. , the contacts of relays 4206 and 4207, the separate conductors in the control circuit such as the conductor 4229, to the battery by the windings of a number of relays such as 5206 to 5210. At this time, all relays 5206 to 5210 are actuated. This is done to prevent errors, or to realize if they exist, in the control circuit, since later, when the circuit is made particular to the calling junction, only one of these relays must remain blocked.

   While operating, relay 4314 also extends the earth of conductor 4300 through the contacts of relay 4310, contact 13 of relay 4314, contact 13 of relay 4206 and a similar contact of relay 4207 to conductor 4234 which is connected by the winding. control circuit, and the 5205 start relay to the bat-

  <Desc / Clms Page number 46>

 laughs. In operation, relays 5206 to 5210 and a start relay 5205 establish a series circuit to operate relay 5203, which circuit can be followed from the battery by the winding of relay 5203, the contact. 1 of relay 5210 and a series of other contacts up to contact 1 of relay 5206, contact of start relay 5205 and contact 5 of relay 5210 to earth on the relay operating circuit 5210.

   In operation, relay 5203 establishes for itself a blocking circuit by contacting relay 5204 to ground through conductor 4222 to contact 5 of relay 4207. This relay also establishes a holding circuit for relays 6210 and 6213 and connects the battery through the coil of relay 5202 to conductor 4223. The battery on conductor 4223 operates relay 4310 since, as noted it is extended by a contact of relay 4207, contact 2 of relay 4206, contact 2 of relay 4314 and the winding of relay 4310 to earth. While operating, relay 4310 opens the earth circuit extending from the calling incoming junction through its contacts and for this reason this earth from the incoming junction on conductor 4300 is now only extended through contact 7 of relay 4314 .

   The start relay 4311 drops out and the control circuit relay 5205 drops out.



  This restores the normal state of all control relays contained in group 5206 to 5210 except the one associated with the calling incoming trunk, which in this example is relay 5210, which remains actuated. On falling, relay 5205 establishes an operating circuit for relay 5207, through contact 5 of relay 5203, rear contact of relay 5205, contact of relay 5210, to ground, on conductor 4228.

   The following circuits are established by the contacts of relay 5207: (1) Relay 5211 is actuated by an obvious circuit which is

  <Desc / Clms Page number 47>

 blocks to earth on contact 1 of relay 5203; establishes a circuit comprising: the battery, the coil of the relay 6304, the contact 6 of the relay 4210, the conductor 4227, the contacts 6 of the relay 4207 and 4206, the contact 6 of the relay 4314, the contacts of the crossbar switch and the maintaining electromagnet, when the cross-bar switch is actuated as explained later in the description. Relay 5211 opens the operating paths for relays 5206 through 5210, but does not open relay 5210 blocking circuit.

   Relay 5211 also connects the earth of the normal contacts of relay 6303, to one of the ten conductors 4230 to 4231, through the contacts of relay 5206 to 5210. In this case, it is assumed that the earth is connected from the contact 7 of relay 5210 to conductor 4230 extended by contacts 9 of relays 4207 and 4206, to contact 9 of relay 4314. Contacts 9 and 10 of relay 4314 representing ten junctions have connection terminals by jumper wire 4330-4340, related to their armatures. A number of Category 4341, 4342, and 4343 pins are connected to 4314 Relay armatures 11-12 and may be jumpered to pins 4330 through 4340 depending on the category of the calling incoming junction being served.

   A number of conductors, represented by a conductor 4232, are connected between the category contacts of relay 4314, and category relays 5304, 5306 and 6205 in the coupling control circuit. One of these latter relays is actuated to indicate the operating mode of the control circuit for the category of junctions served. In this example, it can be assumed that pin 4330 is jumpered to pin 4341 and the category relay has operated, which identifies the calling trunk as being of the category of calls elapsed by l 'operator

  <Desc / Clms Page number 48>

 without cords. Relay 5304 indicates the category of the incoming junction by connecting the battery to one of the three conductors connected to normal contacts 4, 5 or 6 of relay 5209.

   This circuit includes: the battery, resistor 6420, normal contact 9 of relay 6402, normal contact 4 of relay 6304, contact 3 of relay 5304, normal contact 3 of relay 5306, normal contact 3 of relay 6205, contact 4 of relay 5209, previously actuated and conductor 4235 which is used to represent the three conductors extending to coupling relays 4314. Conductor 4235 extends to the contacts of relay 4207, and of relay 4206, at contact 14 from relay 4314, to earth, through the winding of relay 4318. a There are a number of relays similar to relay 4318, to associate the test leads coming from the control circuit to logger-senders. arrival, to the output recorders-senders, to the position channels, etc ...

   The circuit established by winding a relay such as 4318 depends on which category relay 5304, 5306 or 6305 has been actuated. In operation, relay 4318 shown establishes a circuit through lead 4344, through the contacts of relays 4206 and 4207 to driver control circuit 4239 to operate relay 5301 and connect a large number of test leads, such as than 4345, from the position circuits without leads, to allow the control circuit to find a free position channel.

   Each conductor is connected to a track in a switchboard position without cords to which an incoming trunk junction can be connected if this channel is free and if an attendant is present at the position. The test can be entered in all or part of the different switchboard positions and can

  <Desc / Clms Page number 49>

 also enter a number of lanes in each of these positions. In order for rapid service to be maintained, the conditions set out above are required, so that a clear route to an operator position can be immediately found under normal traffic conditions.

   There is a relay in the control circuit for each test conductor, extending to the tracks of the cordless operator positions. Only two of these relays 6207 and 6212 are shown. A circuit is established for one of these relays when a free channel to a free operator position is found.



   Position relay 5508 is actuated when an attendant is present in a position and is not busy establishing or monitoring other communication.



  The test circuit can therefore be traced from earth to a contact of relay 5508, to contact 2 of relay 5512. There is only one relay 5512 for each of the channels in one position. This relay is activated when the channel is occupied and trips when it is free. If there is a free channel in the position, one of these relays is triggered and consequently the earth is extended from a contact on the relay 5508 by the contact 2 of a free junction in the position and the conductor 5542 to one of a number of relay 4318 contacts. A test circuit is shown comprising: contact 2 of relay 4318, conductor 4345, contacts of relays 4206, and 4207, and conductor 4256 in the control circuit.

   This conductor extends through contact 4 of relay 6206, and the winding of relay 6207 to the battery actuating the latter relay, which indicates that the channel associated with relay 6207 is free.



   Recall that relay 4318 also established an operating circuit for relay 5301, this

  <Desc / Clms Page number 50>

 in order to connect the earth to the time switch 5411, to release the control circuit if it is found that all the channels are occupied. The circuit for switch 5411 includes: ground, relay contact 5301, relay 6402 contact 1, relay 6307 contact 5, and switch 5411 armature. Relay 5301 also establishes a circuit. earth by the contacts of relays 6206 to 6211 for a circuit which will be described later. The earth associated with switch 5411 establishes a circuit for relay 5407.

   The continuous movement of the switch combines its grounding with a circuit going through contact 2 of relay 5407 and the winding of relay 5406 to the battery, which causes relay 5406 to operate. to turn, switch 5411 restores a grounded circuit with contact 2 which now establishes a circuit through internal contact 1 of relay 5406, contact 2 of relay 6404, the winding of relay 6308 to battery, which operates relay 6308 to establish the control unit release circuit, which circuit includes: ground, relay 6308 contact 1, release relay winding 5408, and the battery.



  While operating, relay 5403 causes the control circuit to return to idle, so that this can be used for other links. All free track circuits will have earth connected to their occupancy test conductors, from position track circuits while busy circuits will be indicated by an open conductor. Accordingly, all available track circuits will be represented in the control circuit by an actuated relay such as, for example, relay 6207 and 6212. A chain circuit passes through relays 6207 to 6212, and 6206 to 6211 so that one of the free channels can be taken to be used.

   The association of re-

  <Desc / Clms Page number 51>

 The test leave in the different control circuits to the channels of different positions is modified as to the choice in order to distribute the incoming calls to the different operators. In operation, relay 6207 establishes an obvious circuit to operate relay 6307, which establishes an operating circuit for relay 6406 through contact 10 of relay 6402. Relay 6307 also operates relay 5302 in a circuit comprising: earth, relay 6307 contact 2, relay winding 5302 and battery.



  For relay 6201, a circuit is made from earth to contact 1 of relay 6307. While operating, relay 6406 establishes operating circuits, passing through the right winding of all occupancy test relays. represented by relays 6206 to 6211. Some of these relays were already actuated due to coupling busy states since their left windings are connected by conductor 4224 and 4225, the contacts of relays 4207 and 4206, the contacts 3 and 4 of relay 4314 to the holding electromagnets of the crossbar switches serving this group of junctions. The earth is connected to the holding electromagnets of the occupied switches, causing the associated relays 6206 to 6211 to operate.

   All relays 6206-6211 are now actuated to establish the string circuits by their contacts. The circuits for the preceding relays are established by contacts 1 and 2 of relay 6406 which represent multiple contacts equal in number to the occupancy test relays, such as 6206 to 6211. Relay 6406 also establishes a circuit for relay 6208 comprising: the battery, the winding of the latter relay, contact 4 of relay 6406, contacts 2 of relays 6211 to 6206 and the earth on contact 1 of the

  <Desc / Clms Page number 52>

 relay 5403 which is normal and on contact 3 of relay 5402 which is activated.

   Relay 6208 establishes a circuit for one of a number of such relays such as 5305, and 5307, associated with the preferred available circuit which includes: ground, relay 6208 contact 2, conductors 6215 to 6216, depending on circuit which is preferred among the circuits found free. The circuit passing through conductor 6216 extends through contact 4 of relay 5401 and the winding of relay 5307, to the battery. The circuit passing through conductor 6215 extends through contact 1 of relay 1501 and the winding of relay 5305 to the battery. The actuated relay locks to its operating earth, and establishes a circuit for the associated test relay such as 4321 in Fig. 43. This circuit can be followed as follows.

   Assuming that relay 5305 was actuated, the battery is connected from normal contact 1 of relay 5307 by contacts 4 and 2 of relay 5305, contact 2 of relay 6204, conductor 4255, contact of relay 4207, contact 35 of relay 4206 and the winding of relay 4321 to earth.



   While operating, relay 6208 opens the operating circuit of relay 6203 and connects test relay 6403 to conductor 4253 to perform a double test, which double test circuit includes: the tube plate circuit 6410, the winding of the relay 6403, contact 1 of relay 6208, contact 6 of relay 6212, conductor 4253, contacts 33 of relays 6207 and 6206, contact 1 of relay 4321 and the double test conductor in track d 'a chosen position circuit in which, if free, the battery will be applied by contact 1 of relay 5512.

   Operating as previously described, relay 5305 locks to its operating earth and connects the battery to conductor 4255 through contact 1 of relay 5307, contacts 4 and 2 of relay 5305, the

  <Desc / Clms Page number 53>

 contact 2 of relay 6204, conductor 4255 via contacts 35 of relays 4207 and 4206 via the winding of relay 4321 to earth. This extends the double-acting circuit previously described by contact 1 of relay 4321 to the battery, contact 1 of relay 5512, and resistor 5516.



   Logger-senders are selected by the coupling control circuit in the same manner as described for selecting a position channel.



   The track circuit shown in FIG. 55 shows one of a number of these for establishing circuits between the coupling switches of FIG.



  32 and operator positions without cords (In fig.



  55, FC represents the 1st way, SC the second, LC the last). In order to select a channel, the coupling control circuit is given access to test devices for these channels by connector relays such as 4207 and 4206 as described. A free and available channel is indicated by the presence of earth on the test and occupant conductor 5542 from the contacts of relay 5508 / of the battery on the dual test conductor 5541 from contact 1 of the relay 5512. It will be noticed that as previously described, these extend through the contacts of relays 4318 and 4321.

   When the cordless position is monitored by an attendant and a channel is free, and when the attendant is not busy listening to another call, relay 5508 is actuated by position relay 6507 which is actuated. when the operator's earpiece telephone plug is inserted into the telephone jack. The circuit of relay 6507 can be followed from the battery by its winding and by a contact chain on relays 5501, 5502 and 5503 which represent a number of channels, then by the contact of the relay.

  <Desc / Clms Page number 54>

 telephone jack 7210, the key contact 5610 and relay contact 1 5600 to earth.

   This 5508 occupancy test relay has a number of contacts to provide ground to the contacts of a number of relays such as 5512, one for each track circuit in one position. When a channel is not occupied, relay 5512 is normal to indicate the unoccupied state and earth is thus extended by its contact 2 to the associated conductor 5542. When a channel is occupied, the operation of the re- Theis 5512 causes the appearance of earth on the dual test lead 5541 and the occupancy test lead 5542 is open. The channel is seized by the coupling control circuit after closing the cross points of the coupling switch by the coupling control circuit.

   Closure of these cross points causes earth to feed on conductors 5540 and 5543, which will be monitored later from the coupling control circuit. The earths transmitted by the coupling switch actuate relays 5512 and 5511.



  The coil of relay 5512 is directly connected to conductor 5543 and coil 5511 is connected to conductor 5540 through contact 2 of relay 5504 which is normal at this time. The operation of the relays 5511 and 5512 initiates the operation of the track and the switchgear of the position circuit and will be described in detail after the track has been entered by the coupling control circuit.



   Testing and entering a position channel indicates to the coupling control circuit that it can continue to associate the crossbar coupling switches of FIG. 32 to the chosen channel (Note in Fig. 32 that the TSS wires lead to another secondary switch). Tube test relays 6403 and 6405 were connected to dual test lead 4253.

  <Desc / Clms Page number 55>

 



   This circuit includes: battery 5520, resistor 5516, relay contact 1 5512, conductor 5541, contact
1 of relay 4321, contact 33 of relay 4206, the contact corresponding to relay 4207, conductor 4253, contact 6 of relay 6212, contact 1 of relay 6208, the winding of relay 6403 and the plate of test tube 6410.



   If no other control circuit tries to grasp the coupling at this time, the resistance of the tube plate 6410 will drop instantly, thus making the selected coupling occupied for the other control circuits. This also provides an operating circuit for relay 6405 to the tube plate circuit through contact 6 of relay 6406 and contact 4 of relay 6404. By operating, relay 6405 establishes an operating circuit for the relay. 6402 and a blocking circuit for relays such as 6207 to 6212. The double-test character of relay 6405 is important when two identical track circuit tests are performed by two control circuits at the same time so that the tubes such as 6410 instantly operate in both control circuits.



  In this case, neither of the 6405 relays in the two control circuits is functioning and a different circuit is chosen so that the disputed circuit can be seized for another call. The contested track circuit will remove the earth from its busy test lead 4253 when gripped by another circuit, causing the associated relay 4321 to trip and cause that relay to trip and advance the switch. 6405 test relay until the next available circuit. The role of relay 6403 is to make the coupling control circuit count by time and transfer the devices to avoid operating a warning device when two circuits prevent each other from entering the circuit.

  <Desc / Clms Page number 56>

 longed for.

   In this case, relay 6402 does not operate and for this reason relay 6403 connects earth to switch 5411, so the switch will operate relays 5407 and 5406 as described here. Since the operating time of the vacuum tube is negligible, repetition of the first unsuccessful attempt to enter a particular circuit is extremely unlikely.



   Relay 6402 actuated by relay 6405 for input of a free line switch establishes a blocking circuit for itself to earth through contact 3 of relay 6406 and establishes an operating circuit for relay 5303 comprising: battery, its winding, contact 2 of relay 5302, previously activated, contact 4 of relay
6402, normal contact 3 of relay 6303 and earth. While operating, relay 6402 removes the battery from the 4235 category conductor as previously followed by the battery by resistor 6420, contact 9 of relay 6402, contact
4 of relay 6403, the category relay 5304 contacts up to conductor 6235, thereby tripping all track relays, such as 6207, except the one blocked for call.

   Operation of relay 6402 further establishes operating circuits for relays 6306 and 5208. The operating circuit for relay 6306 can be traced from earth through the contact.
3 of relay 5403. The operating circuit for the relay
5208 consists of the battery, contact 6 of relay 5403, contact 6 of relay 6402, contact 1 of relay 6201, contact 1 of relay 5209, coil of relay 5208 and earth. Relay 6402 also opens the earth circuit through the contact of relay 6403 which is extended to switch 5411. By operating relay 5303 connects the battery to conductor 4243 to actuate the primary selector electromagnet 3204 on the frame coupling.

   This tour includes; the battery, resistor 5230, contact 2

  <Desc / Clms Page number 57>

 of relay 5210, contact 2 of relay 5303, contact 4 of relay 5302, conductor 4243, contacts 23 of relays 4207 and 4206, the winding of the primary selector electromagnet 3204 and earth. While operating, relay 5208 connects the battery to conductor 4251 to actuate the secondary selector electromagnet 3207 of the selected secondary coupling switch, as followed by the battery by contact 3 of relay 5401, contact 6 of relay 5305, contact 2 of relay 5208, contact 3 of relay 6201, conductor 4251, contacts 31 of relays 4207 and 4206 and the winding of secondary selector electromagnet 3207 to earth.

   The primary selector electromagnet 3204 energizes its armature and associates the earth with the contacts 24 of the relays 4206 and 4207 and with the conductor 4244 to actuate the relay 6302. The secondary selector electromagnet 3207 energizes its armature and establishes a circuit through the con- nections. 29 tacts of relays 4206 and 4207 to the conductor 4249 which passes through the coil of relay 6301 to the battery.



   A route has been chosen passing through the coupling switches after testing the holding electromagnets controlling this route, and therefore the next stage of operation is to actuate the holding electromagnets under the control of the coupling control circuit. .

   This is done by the aforementioned operation of relays 6402 and 6301 which establishes a circuit comprising: earth, contact 1 of relay 6303, contact 1 of relay 6302, contact 2 of relay 6301, contact 6 of relay 6208 , contact 2 of relay 6212, contact 2 of relay 6306, conductor 4225, contacts 4 in relays 4207, 4206 and 4314, the windings of the holding electromagnets 3205 and 3208 and the dairy. When the crossing points of the primary switch are closed, a circuit is established for relay 6304 which is actuated by the conductor corresponding to the junction conductor thus corresponding to the ni-

  <Desc / Clms Page number 58>

 calf of the switch to which the control circuit is now associated.

   It will be noted that all these levels are represented on contacts 5 to 6 of the contactor relay 4314. There may however be ten similar contacts representing ten levels of the switch. The circuit of relay 6304 includes: the battery, its winding, contact 1 of relay 5207, contact 5 of relay 5210, conductor 4227 which represents a number of conductors, contacts 6 of relays 4207, 4206 and 4314, the contact 3 of the 3200 cross-bar switch, the operating circuit described above for the holding electromagnets and earth.



  Relay 6304 establishes a blocking circuit to conductor 4227 through contact 5 of relay 5210 and also operates relay 6303 in a circuit comprising: the battery, its winding, contact 2 of relay 6402, contact 1 relay 6301, relay 6302 contact 2, relay 6304 contact 2 and earth When operating, relay 6303 establishes the earth blocking circuit on its contact 1 through contacts 3 and 2 of relay 6402 and operating causes the trip of relay 5303 by opening the circuit of this relay at contact 3. When tripping, relay 5303 opens the operating circuit of the primary selector electromagnet 3204, causing it to trip. However, the switches are held in position by the holding electromagnet.

   Relay 5303 also removes the shunt from the right winding of relay 6401 and connects the two windings of this relay in a series circuit comprising: the battery, resistor 6411, the left winding of relay 6401 , contact 1 of relay 6303, the right winding of relay 6401, contact 3 of relay 6307, and earth. The operating circuit of the holding electromagnets must be constantly maintained and for this reason the control circuit must not release this circuit until a holding earth has been applied.

  <Desc / Clms Page number 59>

 qué by the socket circuit by the switching contacts. The 6401 sensitive polarized relay is used to indicate to the coupling control circuit when this ground has been applied.

   The coupling control circuit thus waits for certain conditions to be met before energizing the release relay 5403. Applying the holding earth to the socket conductor as explained later operates the relay 6401 which partially prepares the relay. circuit to operate the 5403 release relay.



   Position track.



   ----------------
At this moment, the connection has been established by the cross-bar switches (Fig. 32), from the conductors of the incoming junction to a free position track and the following operations take place in the position and in the position track circuits. As previously established, the closing of the crossing points of the crossbar coupling switch due to the operation of the selector electromagnets and the holding electromagnets causes the appearance of earth on the collectors 5540 and 5543 as before. followed, which operated relays 5512 and 5511. While operating, relay 5512 establishes obvious circuits to turn on occupancy lamp 5515 and guard lamp 5517. Relay 5511 establishes an obvious circuit for the guard lamp 5514.

   When operating, relays 5511 and 5512 establish a circuit for the associated track relay that in this example is represented by relay 5503. This comprises: the battery, the winding of the relay 5503, the contact. 1 of relay 5511, contact 3 of relay 5512, contact 2 of relay 5503, contact 1 of relay 6507 and earth. Relay 5503 blocks to the earth applied to its contact 2 and opens the operating circuit of relay 5507 extending through its con-

  <Desc / Clms Page number 60>

 tact 1. When triggering, relay 6507 triggers relay 5508, so that all the channels in the position are made occupied for the time required for the attendant to establish communication.

   When operating, relay 5503 connects the earth of contact 1 of relay 5600 through contact 1 of relay 5503 and the coil of relay 5507 to the battery. When operating, relay 5507 causes relay 5504 to operate from earth through contact 4 of relay 5506, contact 8 of relay 5507, winding of relay 5504 to the battery and changes the constant lighting of the lamp 5514 into a flashing ignition by connecting the switch 5513 in the lamp wire. This flashing light signal indicates to the operator of the position that an incoming junction has been connected to a free position channel, and constitutes a preparatory signal preceding an acoustic signal given to the operator a fraction of a second later.

   Relay 5507 establishes a holding earth circuit through its contact 3 and contact 4 of relay 5512 for holding electromagnets 3205 and 3208 and for blocking relay 5512.



  While operating, relay 5504 closes circuit paths for the talk and signaling conductors of the coupling switch in position, opens the blocking path for relay 5511 which returns to the normal state and closes the operating path for relay 5505 by contact 10 of relay 5504, contact 7 of relay 5600, contact 1 of relay 6603, contact 3 of relay 6503, contact 2 of relay 6604 to earth. Relay 5505 is a marginal verify relay and operates only if no other similar relay in another channel is operating.

   There is an overlapping call state in which another 5505 relay in a different channel can be associated with that 5505 relay, so that in order to function it must wait for the overlapping call.

  <Desc / Clms Page number 61>

 is completed It then functions to connect conductors of the position circuit to the coupling switch.



   While operating, relay 5504 establishes a circuit through the crossbar switches to actuate relay 1212 in the circuit of the incoming trunk interjunction, which circuit comprises: earth, contact 1 of relay 5604, contact 1 of relay 5603, contact 6 of relay 5504, conductor 5546, contact
12 of switches 3203 and 3200, conductor 3231, contact 2 of relay 1220 and the battery by the winding of relay 1212 which locks to the earth applied to the contact
6 of relay 1307 through contact 1 of relay 1320, contact
2 of relay 1202, contact 3 of relay 1304 and contact
5 of relay 1220.

   While operating, relay 1212 removes the coupling start earth from conductor 4300 extending through the contacts of relays 4314, 4206 and 4207 to conductor 4228, causing the relay to trip.
5210 in the coupling control circuit. When tripping, this relay trips relays 5303 and .5207, which triggers relay 6304. When the coupling is made occupied by the application of earth to the holding electromagnets, relay 6401 is actuated. which removes the battery from the driver 4253, causing the test relay 6405 to trip.

   The triggering of this relay and the triggering of relay 6304 which took place before that of relay 6401, establishes a circuit to operate the release relay of the control circuit of coupling 5403 which operates in a circuit comprising: the battery, its winding, relay contact 1 6304, relay contact 6401, relay contact 6405 and earth.



   When operating, relay 5403 trips relay 6306 and relay 5407 operates relay 5405 and

  <Desc / Clms Page number 62>

 removes ground from the chain contacts of relays 6206 to 6211 originally used to actuate relay 6208.



  This last relay also triggers. Relay 5405 locks to the ground provided by relay 5402 and prepares a circuit for relay 5404 that operates when relay 5403 trips, if another call awaits service. Relay 6201 also trips, which removes the battery from the secondary selector electromagnet 3208 on the coupling frame.



  This electromagnet returns to idle, opening the relay 6301 circuit. This causes the coupling chain to remove the earth from the relay 5401 which trips. When tripping, relay 6208 opens the circuit of relay 5305 which opens the battery circuit for relay 4321, thus triggering the relay on the frame of the coupling which commanded the double test of the circuit of the selected channel, and made additionally trigger relay 6207 which was used to establish the position channel link. The battery is also removed from the relay of test circuit 6405. On tripping, relay 6207 opens the circuit of relay 6307 and removes the earth of the associated conductors. Relay 6307 opens the circuit of relays 6302 and 6406.

   When tripping, relay 6406 triggers relay 6402 which now opens the circuit of relay 6303, and the release relay of the control circuit 5403. A circuit is now established by the contacts of the release relay 5403. to activate relay 5204 which remains activated if another call awaits service. If no other relay is waiting for service, relay 6314 trips.



  On tripping, this relay opens the start circuit, causing relay 4201 and relay 4209 to trip. This trips connector relay 4207 and multi-contact relay 4206, opening the circuit for relay 4208 and them. other circuits between connector and control circuit, causing relay 5402 to trip

  <Desc / Clms Page number 63>

 and the associated relays. This removes the ground of the test lead from the control circuit, allowing it to be gripped by another connector.



   Junction category signals.



   ----------------------------------
The operation of the relay described above 5507 in one of the channels connects the earth via its contact 1 to the coil of relay 6508. The relay operates and connects the earth via its contact 1, contact 5 of selais 5600, contact 1 of the normal category 7217 and 7219 relays, and the winding of the 6504 category relay to the battery.



  Relay 6504 operates and connects conductors 5547 and 5548 through its contacts 1 and 2 to the windings of category relays 7221,7222, 7223 and 7224 to the battery through resistors 7225 and 7226 respectively, thereby initiating category determination. Earth from contact 1 of relay 6508 also extends earth through contact 3 of relay 6504 to operate relay 6510.



  Relay 6510 opens conductors 5547 and 5548 extending to the telephone circuit and actuates relay 6511 by its contact 2 to earth on contact 1 of relay 6508.



  Relay 6508 locks to this operating earth by its contact 6. Category signals are passed to the position circuit so that the recorder-sender and the position marker can be guided by the type of the incoming trunk trunk. connected to it. Incoming trunk trunks which are connected by the cordless position for trunk or termination communications can be of the type with call on the circuit or with call on the line and automatic listening of the incoming operator. from remote long distance offices or from tandem offices, and their transmission characteristics may vary.



  For example, an outgoing inter-trunk-trunk trunk must be chosen by the marker for /

  <Desc / Clms Page number 64>

 a call from a remote long distance office that will be directed at its exit to another long distance office.



  On the other hand, if a call is destined for a link which may extend from a long distance office to that interurban cross-bar switching office and there terminate at a local subscriber station, it does not. It is not necessary to use a trunk trunk having transmission characteristics equivalent to those of the trunk used for the intermediate call. There are also junctions which have these characteristics with regard to the transmission qualities but which have a difference in the signaling devices, such as the difference in signaling existing between the trunk trunk trunk with call on the line and automatic listening of the arrival speratsice and the inter-city interjunction junction with call on the circuit.

   The category signal in each case indicates the species of the junction by associating a grounded circuit which may or may not include a resistor in series with it and open circuits in various combination with the category relays. These are connected from the junction circuit through the contacts of relay 1301 or a similar relay in the various inter-city inter-circuit circuits by conductors 3223 and 3224, the cross-bar switches in Fig. 32, conductors 5547 and 5548 to category relay 7221,7222, 7223 and 7224. These relays are marginal and operate accordingly according to the resistance in series with the excitation circuit. Below are examples of some combinations made.

   If an earthed resistor is connected to conductor 5547, and if conductor 5548 remains open, relay 7221 operates, this ui energizes relay 7217. Relay 7217 is actuated by the contact of relay 7221 to earth, on contact 11 of the

  <Desc / Clms Page number 65>

 relay 6511 and hangs at this same earth. When conductor 5547 is directly connected to earth, without there being any resistance in series with it, relays 7221 and 7222 are actuated which causes relays 7217 and 7218 to operate, both blocking at earth on contact 11 of relay 6511.

   The same combination is used where conductor 5548 is either connected directly to earth or connected to earth through a resistor, which operates relay 7223 in one case and both relays 7223 and 7224 in the other case. This causes relay 7219 or both 7219 or 7220 to operate, which block in the same manner as described for relays 7217 and 7218. Other and various combinations are commonly used to indicate the characteristics of different junctions. are transmitted later to the recorder-sender and marker used to connect the incoming trunk to an outgoing trunk trunk having the same transmission characteristics.



  * Note that when a category determination is made, the operating path for relay 6504 is opened by the operation of relay 7217 or 7219, thus causing relay 6504 to trip.



  On tripping, relay 6504 operates relay 6509 and trips relay 6510. Relay 6509 circuit includes: earth, relay 6511 contact 5, relay 6504 contact 5, relay 5600 contact 5, winding of relay 6509 and battery. When operating, relay 6509 associates earth with conductor 5549 to operate sission relay 1301 of the incoming junction through a circuit comprising: earth, contact 1 of relay 6509, contact 9 of relay 5504, conductor 5549, contacts 6 of switches 3203 and 3200, contact 4 of relay 1212, the winding of

  <Desc / Clms Page number 66>

 relay 1301 and the battery.

   Relay 6510 is a delayed trip relay and prevents further action in the position until sufficient time has elapsed to ensure that split relay 1301 has operated. The split relay dissociates the inner and forward ends of the junction and associates the forward end with the circuit in the uncorrupted position. However, before the split relay operates, a check for socket holding earth is made by applying earth to the inner socket conductor 5550 by operation of relay 1304 in the incoming junction, as previously described.

   If this earth is present and if the conductors between the position and the incoming junction are closed, the 6505 relay will operate in a circuit comprising: the battery, the windings of the 6505 and 6506 relays in series, the contact 5 of the 5604 relay, the contact 6 of relay 5609, contact 5 of relay 6601, contact 4 of relay 6603, contact 7 of relay 5507, conductor 5550, contacts 9 of the coupling switches (Fig. 32), conductor 3228, contact 9 of relay 1301, contact 4 of relay 1304 and earth. Relay 6505 is blocked to earth on contact 8 of relay 6511.

   This low resistance holding earth is later used to hold the switch hold electromagnets of the incoming and outgoing coupling frames, Figs. 9, 10 or 14, 15 and some relays in the incoming and outgoing junctions if at these times the split relay 1301 of the incoming junction is actuated.



  In the circuit followed above for a new call, relay 6506 does not work. This distinguishes between new calls and callbacks by checking to see if there is an established link. After relay 6505 and split relay 1301 in the incoming junction circuit have operated,

  <Desc / Clms Page number 67>

 the marginal test relay 6506 operates if the holding electromagnets of the cross-bar switches of an externally established link associate the battery circuit followed by the winding of relay 6506 to the earth applied to contact 8 of relay 6511 , indicating a callback on an already established link.

   A circuit is established for relay 6600 by contact of relay 6506, contact 4 of relay 6511, contact 2 of relay 6510, contact 5 of relay 5600, to the earth applied to contact 1 of relay 6508. While operating , the relay 6600 supplies the earth to the circuit of the position to light one of the reminder lamps, 7117, 7118 or 7119; whose role will be explained later. If no connection has yet been made, relay 5506 will not work to me at this time but will eventually work when the marker has established the connection and returned to idle.



   The forward relay, such as position track 5505 is actuated if no other forward relay in the sequence circuit is actuated. A circuit for this relay is established when the backward relays 5504 and 5507 of the track are operating. Relay 5505 establishes a circuit for relay 5608 by an obvious circuit, and this latter relay establishes a circuit for relay 6503 which connects the forward and reverse parts of the position circuit together for use in the circuit. same call. The circuit of relay 6503 can be traced from earth through contact 3 of relay 5608, contact 3 of relay 6603, winding of relay 6503 and battery.

   In order to indicate to the attendant the type of call to be answered, an arrangement of signals is provided which are given by combinations of relays in the circuit of the position under the control of the circuit of the junction. inter-urban interjunctions with call on the incoming circuit (Figs. 12 and 13) or trunk circuits

  <Desc / Clms Page number 68>

 Incoming trunk interjunctions of other species which have switchgear responding to different signals transmitted over trunk lines or The operation of switchgear in the junction / incoming circuit under different conditions connects junction to the battery by different resistance values to conductor 3226 which can be followed by the switches of the coupling and (Fig.

   32) to conductor 5540 and from there through the windings of the marginal relays 7121, 7122 and 7123 to earth. The number of these actuated relays depends on the value of the resistance associated with them responding to calls from different species. For example, when the call is a new call for the link with an outgoing trunk trunk, relay 1212 is actuated, which associates resistor 1211 in the circuit with relays 7121,7122 and 7123. The value of the resistor 1211 is such that only relay 7121 is actuated.



  This establishes a circuit for relay 7106 to earth on contact 12 of relay 6511. Since this is a new call, the apparatus will be in the proper position to establish a circuit for the relay. 7124 from the battery by its winding, contact 1 of relay 6600, contact 3 of relay 6511, contact 1 of relay 6510 and earth. This will establish a circuit to give the operator a distinctive call, as described later. In the case of a callback by the calling remote operator, the same circuits will be established except for the circuit of relay 7124. As explained previously, in the sense of a callback, relay 6600 is actuated and it There would therefore be no circuit for relay 7124.

   Therefore, in the event of a reminder a circuit is established to turn on the call lamp 7117 and a distinctive acoustic signal indicating a reminder is transmitted to the attendant.

  <Desc / Clms Page number 69>

 



   The following lines constitute a preliminary description of the apparatus and the circuits intended to establish a communication with a remote office, but which will be studied now within the framework of the structure of the circuit of the position. In the case of a callback by the called office, by an outgoing junction and the switches of Figs. 9 and 10 or Figs. 14 and 15, which have been previously set to the appropriate position by the marker to establish a connection, circuits are established for the relays 1212, 1320 and 1308 of the incoming junction (Figs. 12 and 13). (Note in Fig. 13 that TTC goes to the test circuit, TSC to the telephone circuit, and TTAC goes to the trunk / trunk allocation connector).



  When operating, the three relays above connect resistor 1310 in the circuit in series with relays 7121, 7122 and 7123. The value of resistor 1310 is such that it causes the operation of relays 7121 and 7122. As a result operating, the two relays 7121 and 7122 establish an obvious circuit for the relay 7105 which establishes a circuit for the lamp 7118 and associates a distinctive acoustic signal with the operator's earpiece.



  A different signal is given when the remote called station does not answer. In this case, the relays of the incoming junction 1212 and 1320 are actuated, which connects resistor 1309 in series with relays 7121, 7122 and 7123. The value of resistor 1309 is such that it causes the operation of all three relays. above. In operation, the three relays establish an obvious circuit for the two relays 7105 and 7106 which make a circuit for the lamp 7119 through their contacts.



   The acoustic signal circuit known as the "order tone", used to indicate to the operators that a connection has been established, is

  <Desc / Clms Page number 70>

 under the control of the acoustic signal relays shown in Fig. 71. The operation of either relay 7105 or 7106 indicates to the operator in the position that the incoming call comes from an inter-trunk trunk with a call on the circuit and also establishes a characteristic circuit. towards the marker. These relays being triggered, circuits are established to indicate that the call comes from an inter-city interjunction junction with call on the line and automatic listening of the incoming operator.

   In the event that two relays are triggered, three order tone pulses are transmitted to both the remote operator and the operator without cables. When only one of the above relays is activated, the acoustic call signal will be transmitted only to the operator without cables. One signal pulse is transmitted when relay 7105 is actuated, and two signals are transmitted when relay 7106 is actuated.



   The command acoustic signal circuit is established from the position control circuit by contact 10 of relay 6511 which associates earth with conductor 7140 by contact, 4 of relay 7108, conductor 7141, contact 4 of relay 7127, contact 4 of relay 7126, the winding of relay 7128 up to the battery. Relay 7128 is the first in a series of operations to energize and de-energize the command signal circuit. This command signal circuit includes: the source of the call signal 7142, various contacts of the relays 7120, 7125, 7126, 7127 and 7128, the right winding 7111 of the acoustic call signal transformer 7109 and Earth .

   The acoustic call signal is transmitted by induction by the winding 7110 of an acoustic call signal transformer 7109 via contacts 1 and 5 of relay 7108 to the conversation conductors which in one case extend through the contacts 1 and 5 of relay 7203 and

  <Desc / Clms Page number 71>

 the windings 7205, 7206 and 7207 of the transformer 7204, by induction by the coil 7208 to the operator's receiver without cables.

   As previously established for certain calls, the order acoustic signal is only transmitted to this operator without cords, but in the case of a call on a long distance interjunction trunk with a call on the line and automatic listening of the telephone. incoming incoming attendant, when relays 7105 and 7106 are both triggered, the acoustic call signal is transmitted by contacts 1 and 7 of relay 7106,1 and 8 of relay 7105, then by contacts of relays 7102 and 7101, contacts 4 and 5 of relay 5504, conductors 5544 and 5545 to the conductors of the junction. The sequence of operation of the audible call signal relays is as follows: relay 7128 operates to the earth applied to contact 10 of relay 6511 as previously followed.

   Operation of this relay establishes a circuit for relay 7127 to the same earth through contact 4 of relay 7128 and contact 4 of relay 7126. When operating, relay 7127 closes the acoustic call signal circuit. contact 3 from the call signal source and the call signal coil 7111. The relay 7127 blocks by its contact 4 and the contact 4 of the relay 7126, and opens the operating circuit for the relay 7128 which trips. che. A circuit is therefore established for relay 7126 through contact 5 of relay 7127 and contact 3 of relay 7128. When operating, relay 7126 opens the acoustic call signal circuit to terminate the first signal pulse. 'call. The circuit of relay 7127 is opened by the operation of relay 7126, which causes it to trip.

   A circuit is now established for relay 7125 through contact 1 of relay 7126 and a circuit

  <Desc / Clms Page number 72>

 blocking is established by its contact 3. This sequence of operations again establishes an operating circuit for relay 7128 through contact 6 of relay 7126 and contact 4 of relay 7127. A second acoustic signal pulse from call is now initiated when the call signal circuit is closed again by contact 1 of relay 7128, normal contact 1 of relay 7127, contact 1 of relay 7125, which is actuated by coil 7111, until To the earth . The circuit of relay 7126 was opened by operation of relay 7128 and returns to idle.

   A circuit is now established for relay 7127 which is the same as the circuit which was previously established, and a circuit is also established for relay 7120 by contact 2 of relay 7125 which is held blocked, the contact 2 of relay 7127 and contact 1 of relay 7126 to the primitive earth, as followed from contact 10 of relay 6511. Relay 7120 locks on this same earth. While operating, relay 7127 opens the circuit for relay 7128, causing it to trip and opening the call signal circuit which terminates the second acoustic call signal pulse.



  A circuit is now established for relay 7126, which circuit is the same as the circuit previously established for this relay. This again closes the call signal circuit for a third call signal pulse and opens the circuit for relay 7127. This call signal circuit which is the last call signal tone circuit established, can Be followed by the call signal source 7142 by relay contact 1 7128, relay contact 2 72126, relay contact 3 7120 and the call signal coil winding 7111 to ground.

   A circuit is now established for relay 7128 through contact 6 of relay 7126, contact 4 of relay 7127, conductor 7141 to primitive earth, and the

  <Desc / Clms Page number 73>

 relay 7128, when operating opens the call signal circuit, ends the third pulse and also establishes a circuit for relay 7108 through contact 1 of relay 7120, contact 2 of relay 7127, contact 2 of relay 7128 to land of origin. In operation, relay 7108 establishes a blocking circuit for itself through its contact 4 and conductor 7140 to earth. While operating, relay 7108 separates conductors 7140 and 7141 at its contact 4, thereby tripping all relays that were held to this ground, including relays 7120, 7125 and 7128.



   The foregoing lines explain the operation of the acoustic call signal circuit when a series of three call signals is initiated in the event that a call enters the long distance office through a trunk with call on and line / set. automatic listening of the incoming operator, signals which are heard by the operator without cords and the long distance operator who requested communication in a remote office both in the case of a new call and in the case of a callback by the remote operator who requested the call. During a call of this kind, neither relay 7105 nor relay 7106 is actuated.



   As previously described, where no use is made of a trunk with call on the incoming circuit for an incoming call, relay 7106 is actuated when the call is a new call or a callback from the calling remote operator. . When establishing a callback from the remote calling office where the called station does not answer, relay 7105 # is actuated, In the switchgear arrangement, when the called station does not answer, the two relays 7105 and 7106 are actuated but relay 7105 alone is effective in controlling the signal circuit

  <Desc / Clms Page number 74>

 call acoustics.



   It will be recalled that when the category indications were described, the operation of relay 7121 indicated a new call coming from a trunk inter-trunk junction with a call on the incoming circuit or a callback from the calling end of the line. a trunk interjunction trunk with call on the incoming circuit, and that during this call or this callback a circuit was established for the relay 7106, and, as said, only a pulse is transmitted to the operator without cords. The conversation circuit to the junction. incoming is opened by contacts 1 and 7 of relay 7106 and this pulse therefore does not reach the incoming junction and is not transmitted to the remote toll operator who requested the call.

   With relay 7106 activated, a circuit is established for relay 7108 after a pulse has been transmitted. This circuit includes: battery, winding of relay 7108, normal contact
3 of relay 7105, contact 3 of relay 7106, contact
1 of relay 7126 which is actuated at this moment, conductors 7141 and 7140, contact 4 of relay 7108, contact
10 of relay 6511 and earth. When operating, the relay
7108 separates the conductors 7141 and 7140 and is blocked by its contact 4 to the conductor 7140. The relays of the acoustic call signal circuit are thus triggered and the transmission of the call signal is terminated after a pulse. It will also be remembered that the relay 7105 is actuated during a callback from the called long distance office or when the called station does not answer.

   Relay
With 7105 activated, two pulses are transmitted to the operator without cords, but these call signal pulses do not reach the incoming or outgoing junction.



   When relay 7105 is actuated, operation of the audible call signal circuit relays continues

  <Desc / Clms Page number 75>

 as previously described until relay 7127 operates the second time. A circuit is then established for relay 7108 comprising: the battery, its winding, internal contact 3 of relay 7105, contact 2 of relay 7125, contact 2 of relay 7127, contact 2 of relay 7128, conductor 7141 and earth. While operating, the relay 7108 opens the circuit of the acoustic call signal, as previously described and is blocked by its contact 4 to the driver 7140.



   In some examples, more than one operation occurred at the same time. For example, the 6502 recorder-sender's turn-on relay is actuated as soon as certain relays are in the following positions: Relay 6508 actuates relay 5600 tripped, relay 6510 tripped, relay 6511 actuated, relay 6506 tripped, relay 6503 actuated and relay 6501 tripped.



  The operating circuits for the above relays indicated as being actuated were established as previously described. The circuit for the recorder-sender switch-on relay 6502 therefore consists of: earth, contact 1 of relay 6508, contact 5 of relay 5600, contact 2 of relay 6510, contact 4 of relay relay 6511, relay contact 6506, relay contact 5 6503, relay contact 2 6501, relay winding 6502, and the battery. Relay 6502 is blocked by conductor 6516, relay contact 5609, conductor 5618, normal contact 5 of relay 6604, conductor 6610 to earth, by contact 2 of relay 5608 which was actuated by relay 5505.

   While operating, the logger-sender switch-on relay 6502 establishes an operating circuit for the logger-sender control relay 2408 of the logger-sender, which comprises: its contact 3, conductor 2420, coil of relay 2408 and battery. Relay 2408 activates the

  <Desc / Clms Page number 76>

 relay 6501 in a circuit comprising: the battery, its winding, conductor 6515, contact 2 of relay 5609, conductor 2421, contact 8 of relay 2408, and earth. Relay 6501 is blocked on this same earth, by its contact 1 and the conductor 2421. This opens the operating path of the recorder-sender start relay 6502 which now remains actuated under the control of its blocking circuit. .

   The above relay 6501 is a delayed operation relay to prevent the recorder-sender from being picked up too quickly.



   The elements of the position recorder-sender can be roughly divided with regard to their functions, into the following main parts. The keyboard, the recorder circuit, the connector control circuit to associate a connector between the recorder-sender and the marker and control relays to establish circuits going through the connector to the marker to control the operation of the device. the apparatus of the marker.



   The keyboard is of the locking type and consists of eleven rows of keys each comprising ten individual keys.



  The eleven rows are numbered 0 to 9 from the bottom and may have letter designations in addition to the numbers for the position designations used in some cases. The key 3401 to the left of the call sign keys is used to associate incoming calls with the call order table (not shown). During calls to the call order table, the cordless attendant will activate key 3401 and forward the attendant's number to the first row of keys.

   Key 3401 operates relay 5704 in the recorder-sender which establishes a circuit through conductor 7484 to actuate marker relay 4701 which transfers the records.

  <Desc / Clms Page number 77>

 to a different set of relays to extend the call to the call order table. For all other calls, the cordless attendant puts the keys with area codes 3403, 3405 and 3407 in the appropriate position and continues through the keypad in the regular order when the digital keys are needed to set the recorders. Earthed circuits are established for the keys of code 3403, 3405 and 3407 by the operation of relay 5701.



  Grounded circuits for the digital keys are established by the operation of a power key 4530 which is energized after the digital keys have been placed in position. Activation of key 4530 establishes a circuit for the start relay 5705 which keeps the contacts closed for later use and at this time establishes a circuit for relay 2411 through conductor 5735. This circuit includes: ground, relay 6714 contact 3 when actuated, relay 5705 contact 4, conductor 5735, relay 2411 winding and battery.

   The digital keys are required for termination calls, where an extension is established in an area office in which that interurban office is located and for calls requiring the services of an outgoing recorder-sender. The keys recording the area code and the recorder relays of this inter-city office are provided with such wiring that a distinction is made between long-distance calls which are extended to another long-distance office and long-distance calls which terminate locally. . For example the trunk codes are arranged in such a way that a 0 or a 1 appearing as the first sign of the code indicates in a definite way that the call must be extended to another long distance office and that the connection must be established by the intercity switch train, of Figs. 14 and 15.

   For this purpose, when key 0 of keyboard 3403 is pressed, a positive signal

  <Desc / Clms Page number 78>

 is recorded by the operation of recorder A1 relay 3309 of the recorder-sender and relay 3312 of the recorder-sender A4 recorder.



  (Observe that in Fig. 33, R designates the A code recorder). This recorder is transferred later to a chosen free marker and therefore the relays A1 and A4 of the marker recorder are actuated to indicate that 0 is the first digit of the callsign. This is also true of key 1, which sets relay 3310 of recorder A1 in the recorder-sender to the appropriate position, which later sets the relay of recorder A1 to the appropriate position. of the marker to indicate that the first digit of the code is 1. In another case, the code registers are set to the appropriate position in a manner well known in the art.

   For example, when the attendant places key n 1 of keypad 3403, 3405 or 3407, an obvious circuit is established to operate relay n 1 of relays 3309, 4400 and 4404 of recorders A. , B and C.



  (the latter designated by BR and CR). Key # 2 sets recorder relays 3311, 4401, and 4406 to position. Key # 3 sets recorders 1 and 2 which in recorder A would be 3309 and 3.11. Key # 4 will set recorder # 4, relays 3312, 4402 and 4407. Key # 5 will set recorder # 5 which are relays 3313, 4403 and 4480 to position.



  The other keys set the position of the recorders which are added to establish a circuit through the particular conductors to adjust the position of the recorders of the marker following the call sign recorder. For example, key 6 operates recorders 1 and 5, key 7 operates recorders 2 and 5; key 8 activates recorders 1, 2 and 5,6, key 9 activates recorders 5 and 4. The activated recorders establish circuits to the marker as soon as the connection circuit.

  <Desc / Clms Page number 79>

 tor was seized and established.

   It can be said however at this time that the records in the recorder-sender establish circuits through conductors 7456, 7457, 7458 and 7459 to set the recorder relays A of the marker of Fig. 46 (AtR ) depending on the records in the recorder-sender. B records are transmitted from recorder relay of recorder-sender B through conductors 7452, 7453, 7454 and 7455 to the relays of recorder B in Fig. 46 of the marker (B'R) and the C records are transmitted from the recorder C relays of the recorder-sender through leads 7463, 7464, 7465 and 7465 to set the relays of the recorder C to position. in Fig. 58 of the marker (C'R).



   For this example, it can be assumed that the stored code is 057, which indicates an intermediate long distance call, which should be extended by the long distance train of switches 14 and 15 to a remote interurban office. As soon as the recorder-sender is entered and relay 2408 actuated, as previously described, relay 5701 is actuated to associate ground circuits to the keys with code 3401, 3403, 3405 and 3407. The operating circuit of relay 5701 consists of: earth applied to contact 2 of relay 2408, conductor 5715, contact 3 of relay 5700, coil of relay 5701 and battery.



   The operation of relay 5701 extends this earth from contact 2 of relay 2408 through contact 1 of relay 5'101, contact 4 of relay 5703, conductor 5717 to keys 3401, 3403, 3405 and 3407. The operation of key 0 in keypad 3403 connects this earth through the coil of relay 3312 and through the coil of relay 3309. The operation of key no. 5 in keypad 3405 establishes a circuit from this earth, for example

  <Desc / Clms Page number 80>

 the winding of the relay of the recorder B n 5-4403.



  The operation of key # 7 in keypad 3407 associates earth with the winding of relay # 5-4408 in the C-recorder circuit and also by the lower winding of relay # 2-4406 in the control circuit. recorder C. By operating these relays establish circuits as said previously, to actuate the recorder- marker relays, 1 and 4 of recorder A5 of recorder B and 2 and 5 of recorder G. Operating as shown above, the logger-sender relays circuit for battery relay 5700 through its winding, conductor 5718, contact 3 of relay 4408, contact 3 of relay 4403, contact 4 of relay 3309 to earth.

   The 5700 relay circuit is established after at least one recorder in each recorder set has been set. This relay now initiates the selection of a connector circuit to link the recorder-sender to the marker. While operating, the 5700 relay trips the 5701 relay which establishes a circuit to operate the 6700 relay which includes:

   the battery, the lower winding of relay 6700, contact 3 of relay 6703, contact 1 of relay 6707 or 6708, previously activated by the recorder-sender, contact 8 of normal relay 6714, contact 2 of relay 5700 , contact 2 of relay 2408 and earth. Either of the above relays 6707 and 6708 or these two relays are actuated when the recorder-sender is seized following the category record of the calling incoming trunk or the record made by the operator without cords under the keys of the call sign recorders.



   When the transmission characteristic of a

  <Desc / Clms Page number 81>

 Calling incoming trunk is the one used for intermediate calls to an outgoing trunk trunk extending to another trunk office, relay 6707 is actuated from the battery by its winding, contact 4 of the relay 6714, to ground, on the 7219 category recorder relay which has been actuated as previously described by a circuit to the incoming trunk trunk.



  When the transmitting characteristic of the calling incoming trunk is that which terminates in the long distance office area, a terminating call, relay 6708 is actuated from the battery by its winding contact 1 of relay 6714, conductor 7324 to earth on contact 4 of the 7217 category relay, also actuated by a circuit as previously described, extending to the incoming junction. In some cases for intermediate calls in combined groups, relays 6707 and 6708 are both actuated. In the case of a long distance call, with relay 6707 actuated or both relays 6707 and 6708 being actuated, relay 5703 responds to indicate to the marker that a trunk link should be established.

   When relay 6507 only is actuated, a circuit can be drawn for relay 5703, which includes: the battery, its winding, contact 3 of relay 5704, contact 4 of relay 6707, contact 3 of relay 6708 and Earth . When relays 6707 and 6708 are both actuated, and when the call sign registers are set to the appropriate position to direct the call to an outgoing trunk trunk, the circuit of relay 5703 is established by the relays. recorder and can be followed by the battery by its winding, contact 3 of relay 5704, contacts 3 and 2 of relay 6707, contact 7 of relay

  <Desc / Clms Page number 82>

 6714, conductor 6723, contact 6 of relays 3307 and 3308, contact 6 of relay 3309, contact 6 of relay 3311 normal,

   to earth on contact 1 of relay 2408. As previously established, logger relay 3309 is operated by key 0 and thus indicates a long distance call when relays 3311 and 3313 are normal. Clearly, if relay 3311 or 3313 is actuated, as might be the case for a termination call, the circuit followed above for relay 5703 would not be established.



   There are optional features in the trunk system to transmit call sign indications to the marker. For three-digit networks it is necessary to transmit the indications to the marker from the call sign registers A, B and C. In two-digit networks, and other special networks, it is only necessary to transmit indmcations to the marker from recorders A and B with if possible a 0 for recorder C which actuates relays Cl and C4 to transmit 0 to the recorder of the marker. For a 1-digit network and other special networks, it is necessary to transmit the marker indications only from recorder A with a 0 from recorders B and C.

   This would mean that relays 1 and 4 are actuated in both registers B and C. This also applies to call sign indications for links with special operations. The TX 3401 key activates relay 4701 in the marker so that the call is made to a special attendant.



   Marker connector.



   ----------------------
When the digits of the office code have been

  <Desc / Clms Page number 83>

 recorded in the recorder-sender and the relays 5700 and 6700 have been actuated or when the recorder-sender has recognized a new order signal, it establishes a start circuit to actuate a marker connector driven in Figs. 73 and 74. The role of the connector consists in entering a free marker in a common group of markers and in associating the recorder-sender with it.



  If no tag is available, the connector waits a limited amount of time for a free tag to become available and grabs that tag to make the appropriate connections. A busy connector is indicated by the nernent function of relay 7302 which associates ground with the 7450 conductor, and a free connector is indicated by the absence of earth on that conductor. While operating, relay 5700 establishes a circuit to test whether the preferred connector is free or busy, which circuit can be followed from the battery by connector 4 of relay 5700, contact 6 of relay 6711, resistor 5720, l winding of relay 5707, conductor 7450, to contact 1 of relay 7302.



  If the preferred connector is busy, and relay 7302 is actuated, the circuit is established for relay 5707 to ground on relay contact 7302. On operation, relay 5707 transfers the connector start lead to another connector (not shown).



  The drive circuit for the preferred connector, as followed later, goes through lead 7451 and for another connector goes through lead 7451A.



  If the preferred connector is free, as will be assumed in this example, relay 7302 remains normal and no circuit is established to operate relay 5707. The connector turn-on circuit, for this reason, includes: battery, contact 3 of relay 6700, contact 4 of relay 6711, contact 4 of relay 6703, contact 6 of relay 6704, contact 3 of re-

  <Desc / Clms Page number 84>

 lais 5707, the conductor 7451, the winding of the relay 7301, and the earth, the latter relay being specific to this recorder-sender in this connector. This connector is shown associated with a number of recorder-senders to each of which is connected a relay such as 7300 or 7301.

   A chain circuit is extended by relays such as 7300 and 7301, to make the connector busy for other loggers-senders in a logger-senders group when a group logger-sender grabs the connector. As stated previously, when a recorder-sender finds the preferred connector busy, it is transferred by operation of relay 5707 to another connector and therefore no conflict is encountered between the recorders-senders of a group for ' grasp connectors to connect recorders-senders to free markers - Relay 7301 operates in the follow-up start circuit, which establishes a circuit for multiple contact relay 7304 to ground, through contact 3 of the relay 7300,

   a chain circuit passing through similar relays associated with a number of recorders-senders, contact 3 of relay 7301, the winding of relay 7304, to the battery as followed by the setting conductor on 7451. When operating, multiple contact relay 7304 now circuits from the recorder-sender through conductor 7445, to obtain use of a free marker. This circuit is extended to a relay associated with the preferred marker. If this marker is occupied, 1 (circuit is progressively advanced by a chain of contacts to find a free marker.

   This circuit, to gain access to a free marker, extends from the battery to the recorder-sender relay 6700, through its contact 3, contact 4 of relay 6711, contact 4 of relay 6703, contact 3 of relay 5703, conductor 7445, contact 6 of relay 7304, contact 2 of relay

  <Desc / Clms Page number 85>

 7401, and the winding of relay 7402 and earth.



   The circuit followed assumes that the marker preferred by this connector is free. If, however, this marker was previously entered by a recorder-sender using a different connector, a busy state will have been established which will have operated relay 7401 in the connector shown here. This would advance the relay circuit. switching on by internal contact 2 of relay 7401 to activate relay 7404, so marker n 2 associated with relay 7404 is free. When this state of affairs exists, marker # 2 is taken to be used in place of marker # 1 and the conductors coming from recorder-sender are extended to marker # 2 by the operation of relay 7406.

   Assuming that marker # 1 is found free, relay 7402 is actuated in the circuit as previously followed, which establishes an obvious circuit for multiple contact relay 7405 to connect the operating and control leads from the logger- sender to the marker. A busy state is also immediately established for the marker in all other connectors, where it appears for service connections with logger-senders. When operating, relays 7402 and 7405 place a shunt on relay 7401 to prevent it from operating when ground is applied to conductor 7498 by the marker, as will be followed later, to make that marker busy for. all recorders-senders associated with other connectors.

   This shunt circuit consists of: earth, contact 3 of relay 7405 and contact 3 of relay 7402, up to a point between resistor 7418 and the winding of relay 7401. Earth is connected by contact 4 from relay 7405 to conductor 7497 extending through the coil of marker relay 5003 to the battery, which operates and connects earth through its 7498 contact which extends through the windings of a number of relays 7401 used for link this marker to

  <Desc / Clms Page number 86>

 recorders-senders, by other connectors.

   As explained above, a shunt was placed around the winding of 7401 in this connector to ground on contact 3 of relay 7405, and for this reason, relay 7401 in this connector does not operate from earth, placed on conductor 7498, but this earth is extended by multiple connections 7409 through the windings of other relays such as 7401 in other marker connectors to which the earth is not connected It is therefore clear that in the other connectors, relay 7401 operates to extend the start conductor to another marker through a chain circuit previously described.

   The operation of the marker preference relay 7402 also connects the earth from contact 5 of relay 7304 to conductor 7499 to actuate relay 6808 which circuit comprises: earth applied to contact 5 of relay 7304, contact 3 of relay 7402, conductor 7499, contact 7 of relay 6807, contact 7 of relay 6806, conductor 6811 through sheets 69,70, 60, 61, 49, 50,51, 40, 30, 20 and 19 at contact 4 of relay 1901 then again through the same sheets through conductor 6810, the coil of relay 6808 and the battery. This last relay operates and locks to the same earth.

   In operation, relay 6808 establishes operating circuits from its contacts 1, 2, and 3 to relays 6801, 6802, and 6803 through obvious circuit paths through contact 2 of relay 6804 and contacts 2 and 3 of relay 6805. Relay 6808 also connects ground to conductors 7467, 7568, and 7469 extending to the recorder-sender circuit through multiple contact relays 7405 and 7304 to conductors 7467, 7468, and 7469 respectively, in the logger circuit. recorder-sender. The 6808 relay also connects

  <Desc / Clms Page number 87>

 earth to conductors 6812, 6813 and 6814 extending to the marker and closes a circuit from the battery through this contact 4, the use of which will be given in the description of the operation of the marker circuit.

   To make it easier to follow the circuit paths from the recorder-sender through the connector to the marker, the circuit conductors have been given the same numbers in the recorder-sender, connector, and marker.



   When the marker connector establishes a link between a recorder-sender and a `` marker, the marker immediately receives the record which has been established in the recorder-sender, record comprising for example the callsign, the preference of the recorder-sender for odd or even crossbar switch rack connectors, details of the type of the incoming trunk through which the long distance call was initiated and the transmission characteristic of that trunk, the direction required by an outgoing trunk and the transmission characteristic of the outgoing trunk, including the cross-bar switch train to be employed in establishing the link.

   The type of outgoing junction to be chosen is automatically given to the marker by the category and type records of the calling incoming junction and by the records of the call sign. The register-sender then informs the marker if a previous attempt has been made to establish the connection from the calling incoming trunk. If for some reason the marker does not perform properly on the first try, its time counter circuit will ground lead 7473 which causes relay 6703 to operate to give the recorder-sender l '' order to release the marker and to proceed to a second subsequent attempt

  <Desc / Clms Page number 88>

 a mode of operation of the circuits which will be described later for this second test.

   When this second test is carried out, a different label is usually obtained, although under certain conditions the same label may be chosen. The time count circuit 5108 is shown schematically associated with a time count switch which operates a series of relays 5104, 5105, 5107,5106 and 5103.



  Relay 5103 connects ground to conductor 7473 through the connector to operate relay 6703 in the recorder-sender. Relay 6703 trips relays 6700 and 5700, which opens the start leads for the connector and marker, thus freeing the leads between them, breaking all direct connections between the recorder-sender and the marker and also triggering all relays used to record indications in the marker.



  As a result, the 6700 and 5700 relays are reactivated to make a second attempt to establish the link. All the recorder relays in the marker, including those recording the above indications, are actuated again, provided of course that none of their conductors are open. Those which are not ground actuated from the recorder-sender, are ground actuated from the contacts of relay 6808 extending to the contacts of the recorder relays of the recorder-sender, as will be shown. in the description .



   Marker records.



   ---------------------------
Considering as a first attempt, the association of the marker to the recorder-sender as previously described, the subsequent recorder relays in the marker are actuated, including the recorders to establish a verification circuit. initial series,

  <Desc / Clms Page number 89>

 some of which may be tripped before the connection circuits are established.

   All the relays of recorders A and B in Fig. 46 and the relays of recorder C in the upper part of FIG. 58 are actuated from the earth placed on conductors 7467 and 7469 by the operation of relay 6808 in the marker or by earths placed on some of the conductors 7452 through 7459 inclusive, and from conductors 7463 through 7466 inclusive by the operation of some of the recorder-sender's recorder relays.

   The earth circuits for conductors 7467 and 7469 can be followed from contacts 1 and 3 of relay 6808 by contact 3 of relay 6805, contact 2 of relay 6804, the contacts of connector relays 7405 and 7304 to the contacts of recorder relay of recorder-sender 3309 to 3313 and 4400 to 4408, inclusive The earth circuits are therefore established by the contacts of all relays of recorders A, B and C of the recorder-sender which ee are not at this moment actuated, and extended by any conductors 7452 to 7459 inclusive, and 7463 to 7466 inclusive associated therewith,

   through the contacts of connector relays 7304 and 7405 to the relay windings of recorders A, B and C of the marker. Relay 5808 is actuated by conductor 7319 from the recorder-sender category relays or from ground on conductor 7468 by conductor 7462 extending to the marker.

   Relay 7005 is actuated from ground on conductor 7468 which is connected in the recorder-sender to conductor 7481. Relay 7004 is actuated by the category relay contacts of the recorder-sender by conductor 7482; relay 4701 is actuated from earth by the contacts of relays 5704 by the driver

  <Desc / Clms Page number 90>

 7484. Relay 5807 is actuated by conductor 7461 and earth by contacts of relay 6704. Relay 5806 is actuated from this same earth.

   Relay 5805 is actuated by conductor 7460 either from earth on relay contact 6702 or from earth applied by relay 6808 to conductor 7468 which, as noted, is connected to conductor 7460 in the recorder-sender. these recorder relays are all actuated, a series circuit is established by their contacts for the operation of relays 6804 and 6805, which can be followed by earth on contact 4 of relay 4601 of recorder A1 by a series circuit extending through the contacts of relays 4602, 4603 and 4604 of recorder A to contact 3 of relay 4605 of recorder B1, through a series circuit extending through the contacts of relays 4606, 4607 and 4609 of recorder B to contact 3 of relay 5801 of recorder C1,

   via a series circuit extending via relays 5802, 5803 and 5804 of recorder B, via contact 3 of relay 5805, contact 6 of relay 4701, contact 1 of relay 7004, contact 4 of relay 7005 , contact 3 of relay 4008, contact 2 of relay 5808, contact 2 of relay 6801, contact 2 of relay 6802 and contact 2 of relay 6803 via the left windings of relays 6804 and 6805 to battery . While operating, the 6804 and 6805 relays remove the earth from the windings of the 6801, 6802 and 6803 relays and from the conductors 7467, 7468 and 7469. By removing the earth from the conductors 7467 and 7469, the earth is disconnected from the windings of the relays of the relays. marker recorders which operated by circuit routes extending through the unactuated relay contacts of recorders AB and C of the recorder-sender.

   By removing the earth from the conductor 7468, we interrupt

  <Desc / Clms Page number 91>

 also circuits as tracking, which are not established by records in the recorder-sender. For this reason, the only recorder relays of the marker which remain actuated at this time are those which are actuated directly from earth by contacts of the recorder relays of the recorder-transmitter in order to record. directions to the marker to guide the marker in establishing the link as notified by the incoming trunk trunk.



   The 6804 relay, while operating, and the 6801 relays,
6802 and 6803 by tripping establish a circuit comprising: earth, contact 1 of relay 6804, contacts
1 of relays 6803, 6802 and 6801, the windings of relays 6806 and 6807 and the battery, which operates these last two relays. While operating, relay 6808 also connects earth to conductor 6812, 6813 and
6814. A circuit is established for the marker relays providing battery and ground 1903 and 1904, comprising: earth, contacts of relay 6808, conductor 6812, extending through leaves 69, 70,
60, 61, 49, 50,51, 40, 30, 20, relay contact 3
1901, the windings of the 1903 and 1904 relays which both trip and the battery.

   Circuits passing through conductors 6813 and 6814 are not established at this time and are used during operation of the marker apparatus.



   Selection of the route relay.



   ----------------------------
Route relays are actuated by circuit routes created by the operation of recorder relays, Figs. 46 and 58, some fiftieth relays and some tens. As we know, the number of relays of the fifties and tens depends on the maximum number of directions that must be established.

  <Desc / Clms Page number 92>

 blies in an office. Two fifties only relays, 5903 and 5904, and two tens relays 5901 and 5902 were shown for typical closed circuit routes for this trunk office. The operating circuits of the 50 relays are established by the contacts of relays 4601, 4602, 4603 and 4604 of recorder A and relays 4608 and 4609 of recorder B.

   The operating circuits of the tens relays are established by the contacts of relays 4605, 4606, 4607 and 4608 of recorder B. The circuits for the operation of the route relays pass through a combination of relay contacts established by the controller. operation of some of the 5801, 5802, 5803 and 5804 relays of recorder C, some tens relays such as 5901 and 5902 and some fifties relays such as 5903 and 5904. Clearly a large number of combinations contacts can be made in the above manner in order to establish circuit routes to operate the various route relays.

   The route relay circuit extends through the route relay windings through the contact combinations made by the above relays to earth on the contacts of relays 6804, and 6805 as will be followed later. An example of a route relay for this trunk office is shown in the right part of Fig. 47 and the left part of FIG. 48 to associate inbound junctions with outbound junctions with particular destinations - There can be approximately as many route relays assigned to inter-office routes as there are junction group relays, which are also known as of terminal block relays, associated with the various groups or sub-groups of outgoing trunks going to long-distance offices.

   Other road relays have the role of

  <Desc / Clms Page number 93>

 to connect incoming junctions from interurban offices to outgoing trunk switching junctions, going to offices located in the inner city area and to junctions extending to tributary offices which may arise either on the frame of assignment to the interurban junctions of FIG. 31 or the termination junction assignment frame of Fig. 51.



  Other route relays are assigned to inter-city trunk groups known here as hop-scan trunk groups which can be reached by a route relay, such as relay 4802, which can be assigned to a group. of junctions which was added in order to enlarge a normal group of junctions. The hop scanning mechanism will be explained in connection with trunk groups that do not have sufficient capacity to handle an unforeseen demand for calls to a particular toll office. This addition of junctions on a jump exploration basis is however only made necessary when there is not sufficient space for the assistant group of junctions on the same frame as the primitive group of junctions.

   The means of associating this group of assistant junctions with skip exploration with the groups of junctions originally assigned to an office will be explained below with regard to the frame number indication system. The terminal block associated with a group of outgoing junctions usually has a capacity of .40 junctions each of which is associated with a road relay to associate the equipment of the marker with the test terminals and the equipment of the outgoing junctions. of the group by the contacts of the multiple contact relays of the terminal block, as shown in Fig. 31.

   There are a large number of similar junction block relays which equates to at least the number of route relays to facilitate pairing of the device-

  <Desc / Clms Page number 94>

 The marker is assigned to all trunk groups and subgroups to assign a link between an incoming trunk and an available free outgoing trunk having the desired destination.



   A large number of three-digit codes may be provided for trunk and service inter-office switching codes; end-sender codes which the recorder-sender receives as 1, 2 or 3-digit codes are usually received by the marker as 3-digit codes in which the recorder-sender replaces the digits omitted by a zero. Examples of arrangements are given below with arbitrary letters for different species of networks.



   Network A, B, C - absence of zero or one in three places,
Network A, B, X - zero or one missing in the first two places.



   Network A, B, - zero or one missing in the first two places.



   Network A - absence of zero or one in the first place.



   Network, A, B'or A, B, X - absence of zero or one in the first two places.



   Network A or A, B - absence of zero or one in the first place.



   Three-digit codes that are not used as local or service codes or that do not start with zero are used as area codes; examples of three-digit area codes can be distinguished as follows:
Network 1 - any code containing zero or one in any place except codes beginning with one, which also have the digit one in the second or third place.

  <Desc / Clms Page number 95>

 



   Network 2 - any code containing zero or one as the first two digits except codes starting with one, which have the number one in the second place.



   Network 3 - Codes containing zero or one as the first digit except for codes starting with one, which have the number one in the third position.



   Network 4 - Where a three-digit combination does not allow sufficient trunk codes, four-digit codes may be used, however these need not be described for the invention making use of the network. subject of this presentation.



   As stated above, outgoing tributary trunks from a cross-bar switch office appear in both the intercity switch train and the local switch train, and as a result, the tributary codes may appear. be either termination codes or interurban codes
Late outside attendant codes can be 1, 2 or 3 digit codes, but no combination of these is used to reach the late outside attendant. can be “centralized II” or “decentralized.” During calls from pulse junctions, the incoming recorder-sender receives from;

   distinctive preliminary digits such as 11, and during calls to the cordless position, the position recorder-sender interprets the lowering of the key of the external attendant with delay as a signal indicating that a delayed exterior code is requested. In either case, driver 7484

  <Desc / Clms Page number 96>

 going to the marker is grounded to operate the 4701 contactor relay which transfers the loggers to a different group of 50's relays to operate the exact route relay, extending the link to the outside operator with delay.



   Incoming long distance calls can be made to groups containing intermediate or combined terminating trunks or any combination of the above three types. The type of trunking required is usually indicated by the first digit of the trunk code, being since zero alone or zero precedes "a" before a registers an intermediate callsign. A / alone or a preceding one or zero records a termination code. In the marker a circuit comprising:

   earth, relay 6806 contact 2, relay 4701 normal contact 5 and logger relay contacts A, B and C (Fig. 46 and 58), when actuated to register an intermediate area code, is used to operate intermediate call sign relay 7002.



  Another circuit coming from the same earth and passing through contact 5 of relay 4701, when activated, goes through the contacts of the actuated relays of recorders A, B and C, to record a termination code and is used. to operate a 7001 non-intermediate code relay, which operates on all termination calls. The intermediate relay 6907 or the termination relay 6908 used to control the test of the junctions in the subgroups is therefore activated according to the direction of the call.



   The existence of two sets of switches, one intended for telephone communications which terminate in the network of the interurban office and the other intended for telephone communications which are extended to interurban offices.

  <Desc / Clms Page number 97>

 remote baths, allows the selection of many more routes to route telephone calls than would be possible with a single set of switches.



   The inter-city inter-junctions connected to each of the two switch trains are of the same type. Trunks known as intermediate trunk trunks are connected by the trunk train of switches, when they extend to a remote trunk office, but are joined by the terminating train of switches, when they extend to an office located in the interurban center network. The type of trunk employed depends entirely on the distance the call must travel, and the type of switch train employed depends entirely on where the call ends.

   A call using an intermediate trunk trunk can be initiated in a remote trunk office, for example, in office A, and can be extended, by the trunk train of switches from that trunk office, to a third trunk office. . A call made in this same remote trunk office, for example in Office A, which must terminate in the interurban office with crossbar switches, must use a terminating trunk trunk and a connection must be established by train. termination of switches.

   A call made to a second remote long-distance office, through the office
A, which is to terminate in this cross-bar switch trunk office, must use an intermediate trunk trunk, which would be extended by the switch termination train in the cross-bar switch trunk office, to a switching outgoing trunk intercity extending to an office located in the reed at the interurban

  <Desc / Clms Page number 98>

 bath .

   The above explanation is given to highlight the advantage of having two switch trains in the cross-bar switch intercity office and to understand the nature of the junctions, which are used in the facility. the various links by the various switch trains.



   Routing by intercity train of switches.



   -----------------------------------------------
A typical route or artery relay arrangement has been shown in the right part of Fig. 47 and in the left part of Fig. 48, for controlling routing to the various types of outgoing trunks, which arrangement appears to include examples of sufficient scope to show the establishment of connections for routing inbound calls, originating from trunk or tandem trunk trunks, to remote toll offices or to termination offices located in the network from the cross-bar switch office to tributary offices located a short distance from the toll center.

   The bunker relays 4702 are arranged in combination to successively associate the marker equipment with two groups of junctions of the same type and to choose free junctions in one and the other group. Route relay 4702 is also wired to selectively and successively associate the marker apparatus by way of example with small subgroups of outgoing junctions of different types under the control of a single route relay.

   By this method an incoming call can be routed to any of three outgoing trunks of different types, i.e. intermediate trunks for trunk links comprising more than two trunk offices, trunks

  <Desc / Clms Page number 99>

 trunk for links from one trunk to another trunk office and combined trunk junctions, which can be used either as intermediate trunk junctions or as terminating trunk junctions. Route relay 4804 is arranged to choose free junctions extending towards the operator. The 4801 route relay is arranged to select only termination junctions.

   The 4802 route relay, known as the jump exploration route relay, is arranged to select junctions, which have been temporarily added to a group of junctions, which can no longer meet the requirements of the necessary service in this group. Assume, as a first example, that an incoming call has been received in this office from a remote trunk operator who has requested a connection, to be directed by another remote trunk office, and that the call is, for this reason, considered as an intermediate call which requires the use of interurban junctions having the best possible transmission qualities.

   It will also be assumed that this group of junctions is large enough to require the service of two total relays 4702 and 4703. In this case, the transfer relay 4701 is normal, the fifty-fifty relay 5904, as is the relay of the 50s. tens 5902, are activated, and the relays of loggers A, B and C (Figs. 46 and 58) must be set for this type of connection.

   Assuming logger relays 4608 and 4601 have been actuated, the 5904 fifties relay operating circuit includes: battery, 5904 fiftieth relay winding, 4701 relay contact 3, conductor 4729, contact 3 of relay 4608 action born, contact 2 of relay 4602 normal, contact 3 of relay 4604 normal, contact 5 of relay 4601, activated,

  <Desc / Clms Page number 100>

 contact 3 of relay 4603 normal, contact 1 of relay 5805 normal, contact 3 of relay 6801 normal, contact 3 of relay 6804 activated and earth.

   Assume that the recorder relay 4607 has been actuated to close a circuit for the tens relay 5902, which circuit includes: the battery, the tens relay coil 5902, the conductor 5950, the contact
5 of relay 4605, normal, contact 4 of relay 4606 normal, contact 1 of relay 4607 energized, contact 3 of relay 6802, normal, contact 4 of relay 6805 energized and earth.

   The above relays being actuated, as well as a particular relay of the fifties of a large group of relays of the fifties and a particular relay of the tens, a circuit is established for the road relay 4702 by the operation of the relay relays. particular recorder 5803 and 5804 which circuit comprises: the battery, the winding of the road relay 4702, the contact 4 of the fifties relay 5904, the contact 2 of the tens relay 5902, the conductor 5932, the contact 2 of the relay d 'logger 5804 activated, contact 2 of logger relay 5803 energized, contact 2 of normal logger relay 5802, contact 1 of normal logger relay 5801, contact 4 of relay 5803 energized, contact 2 of relay 5805 normal, contact 3 of relay 5803 normal, contact 1 of relay 6805 and earth.



   Route relay 4702 operates and thus establishes circuits to try and choose a free trunk from a group of trunks extending to a particular remote trunk office. Connector circuits are used between the marker and the junction blocks of a junction allocation frame of a species similar to that of the connector existing between the record.

  <Desc / Clms Page number 101>

 treur-sender and marker. These connectors are chosen to be used temporarily by the marker, as needed.

   In this example, the contact 9 of the route relay 4702 is connected to a connector activation lead to actuate the activation relay 4803 corresponding to the allocation connector associated with the terminal block containing the inter- junction. Desired outgoing trunk trunks extending to the requested remote trunk office on the inbound trunk trunk.



   When the route relay 4702 has operated, conductors are connected from certain logger relays to the terminal block with which the group of junctions is associated and are controlled by that particular route relay. As previously established, the switch racks and logger-senders are divided into even and odd groups. If an odd-numbered recorder-sender grabs a marker on the first try, the tag's recorder relay 5803 is actuated. If, during the first attempt, the marker is seized by an even recorder-sender, this relay remains normal. An odd logger-sender directly associates ground to conductor 7462, which keeps relay 5808 energized.

   When an even logger-sender grabs a marker, relay 5808 is momentarily actuated by ground applied to conductor 7468, but, when some of the relays described above trip, relay 5808 trips. Assuming that the marker is picked up by an odd recorder-sender, a circuit is established to operate relay 5101, if it is a first attempt, and relay 5102, if it fails. This is a second try. The circuit for operating the relay 5101 comprises; earth, contact 3 of relay 6807, contact 1 of relay 5808,

  <Desc / Clms Page number 102>

 contact 2 of relay 5807, conductor 5927, coil of relay 5101 and battery.

   On a second try, relay 5807 is actuated, which establishes a similar circuit, through conductor 5928, for relay 5102.



  The relays 1903 and 1904 having been previously actuated in a circuit comprising: earth, contact 8 of relay 6808, conductor 6812, contact 3 of relay 1901, the windings of relays 1903 and 1904 and the battery, it will be at We now establish a circuit for actuating the marker preference relay 4119 to associate the member known as the "allocation rack connector" between the marker and the groups of outgoing junction test leads.

   This circuit includes: the battery, contact 8 of relay 1903, contact 3 of relay 5101 which can be assumed to be actuated, contact 1 of relay 5102, which can be assumed to be normal, conductor 4820, contact 2 of relay 4803, the winding of relay 4119 and the battery, then a chain circuit through the relays preferably of the marker, contact 3 of relay 4121 and earth. In operation, relay 4119 establishes a circuit for multiple contact relay 4122, which circuit includes: the battery, its winding, contact 1 of relay 4119, and ground.



  In operation, this latter relay 4122 connects a number of conductors, from the marker to the junction allocation frame, which ultimately provides the test devices to ensure that there is a free junction in the group. of junctions controlled by the route relay 4702.



   The. multiple contact relay 4122 first establishes a circuit to operate the junction check relay 1801 by conductor 4130. Each connector of the group of such connectors assigns

  <Desc / Clms Page number 103>

 can be fitted with a number of terminal block relays such as 3113, 3114, 3115 and 3116, each arranged to connect a group of outgoing junctions, which may include a small number of junctions, for example 5 or 10 junctions, or a greater number of junctions, such as forty outgoing junctions.

   The marker s corresponding terminal block relays, represented by relays 4902 through 4905, are common to the terminal block relays of all connectors representing many different groups of junctions; each connector has the same number of terminal block relays as the marker, which have corresponding designations. To establish a typical circuit, the terminal block relay 4902 is jumpered to contact 10 of the road relay 4702 and is associated by this relay contact to ground with contact 17 of the multiple contact relay 5905. The relay 4902 is therefore actuated when the route relay is actuated, since its winding is associated with the battery by the winding of the counting relay 4901.

   In operation, relay 4902 connects conductor 4921 to conductor 4922. Conductor 4922 is connected to the battery through contact 8 of relay 1903. Conductor 4921 is connected to the winding of terminal block relay 3116 through contact 5 of multi-contact connector relay 4122. Thus, the connector terminal block relay is actuated to associate the joint test leads of the desired joint group with the marker test relays in FIG. 38. Conductor 3125 is shown as an example of a junction test conductor.



   The following operations occur prior to testing the junctions of a group to find a

  <Desc / Clms Page number 104>

 free junction to a particular office. Relay 2807 is actuated in a circuit comprising: the battery, its winding, conductor 4732, contacts 2 and 3 of relay 4710, contacts 7 and 8 of the relay of terminal block 3116, and earth. Relay 2801 actuated in a circuit comprising: the battery, its winding, a series circuit passing through the contacts of the junction test relays 3813, 3812, 3811 and 3810, contact 3 of relay 1707, contact 1 of relay 1801, conductor 1815, contact 4 of relay 6806, and earth.



  The series circuit passing through the contacts of relays 3813 etc., as described, establishes that these relays are all in a condition to establish a junction test and precedes the operation of these relays for the junction test. tion. In Fig. 38, three rows of relays are shown, each row extending horizontally across the figure. There are as many relays in each horizontal row as there are junctions to be tried simultaneously in the largest group or subgroup of junctions in an office, usually forty. En has shown only a sufficient number of relays to give an example of the test devices. From this small number of relays, we can probably get a clear idea of the rest of the equipment and how it works.

   A differential relay 2808 is actuated to continue circuit preparation shortly before testing the junctions in the group controlled by the route relay. It will be noted that the circuit of this relay was established by relays previously activated, but was maintained in the non-operating state by a bypass going from the earth by the contact 7 of the relay 1904 and the contacts of the relays 2807 and 2808. In operation, relays 2807 and 2801 make the operating circuit through

  <Desc / Clms Page number 105>

 the upper winding of relay 2808 and going from the battery, through contact 4 of relay 1903, to the earth applied to contact 8 of relay 1904. While operating, relay 2808 connects earth to the first of relays 3810 and
3813 which is not actuated.

   The relays in this row which are normal (not actuated) represent the free junctions of the group. The first junction of a group of junctions is tried and taken to be used, if it is free, by the operation of relays 3801,
3806 and 3810, the vertical rows of relays shown in this figure representing the test apparatus for the junctions, bearing successive numbers, of a group of junctions.



   It has been assumed that the incoming call to be routed comes from a remote toll office and is to be extended to another remote toll office, which link is known as an "intermediate toll link". For this purpose, the "intermediate" relay is actuated in a circuit established by a combination of recorder relays constituted by the recorder-'sender. Relay 7002 is first actuated in a circuit comprising the battery, its winding, conductor 5943, contact 1 of relay 4603, contact 5 of relay 4604, contact 5 of relay 4602, contact 2 of relay 4601, contact 5 of relay 4701, contact 2 of relay 6806 and earth.

   The circuit established by the logger relays for the relay 7002, establishes a circuit for the "intermediate" relay 6907, which circuit comprises: the battery, its winding, the contact 1 of the relay 7001, the contact of the relay 7002, contact 4 of relay 4808, conductor 4822, contact 2 of relay 6806 and earth. Assuming in this case that all the trunks in the group to be tried extend to the same remote trunk office and are therefore all "intermediate" trunks with high transmission characteristics, an "inter-trunk" relay.

  <Desc / Clms Page number 106>

 mediary "6915 is connected by jumper wire to contact 12 of the route relay 4702 and is actuated when the route relay is actuated.

   This route relay is used for progressive operation in the event that the junctions of this group are all occupied. While operating, relay 6907 establishes a circuit for relay 6909, which circuit includes: battery, right winding of relay 6909, contact 2 of relay 6910, contact 1 of relay 6908, contact 1 of relay 6907 , contact 4 of relay 6806 and earth. This earth is also extended by the contact of relay 6907 to the contacts of the route relay to mark the number of junctions of a group to be tested.



  This marking is carried out by the operation of two of the relays of the upper horizontal row (Fig. 38). If, as assumed previously, all of the junctions in the group are "intermediate" junctions, all of the junctions in the group can be tried to find a free junction.

   In this case, the first relay 3801 is activated and the last relay 3805, is activated, which indicates that one can try all the junctions in the interval to find a free junction. For this purpose, the earth is extended. from contact 4 of relay 6806, as described, through contact 1 of relay 6907, contact 1 of relay 6908, contact 2 of relay 6910, conductor 6921, to contacts 3 and 4 of the multi-contact reset relay earth 5905 and to contacts 3 and 4 of the road relay 4702. In this case, the right contacts 3 and 4 of relay 4702 are also connected by jumper wire to the relays 3801 and 3805.

   The circuit established by contact 3 of relay 4702 operates relay 3801 for the test start point, and the circuit established by contact 4 of relay 4702 extends to the relay indicating the end of the test. , or relay 3805. The operation of these two

  <Desc / Clms Page number 107>

 relay therefore indicates the limit of the test. An example of the same arrangement will be given later, when only part of the group is tested and when, therefore, an intermediate relay is actuated to mark the end point of the test.



   If the first junction is occupied, relays 3806 and 3810 are actuated. The circuit established to find the first free junction of a group is therefore extended by a chain circuit passing through relays 3806 and 3807, etc., until a relay is found which does not exist. has not been activated. This represents the first free junction. A ground is applied to a conductor passing through the contacts of relay 3806 which, if the first joint in the group is free and if relay 3806 is therefore normal, will cause relay 3810 to operate. the junction represented by these relays is occupied, the relay 3806 will be activated and will extend the circuit to the relay 3807. If this junction is free, the relay 3811 is then activated.

   Assuming that the first junction is free, a circuit is established to actuate relay 3810, which circuit includes: the battery, contact 4 of relay 7011, contact 3 of relay 7006, conductor 7043, winding it ment of relay 3810, contact 1 of relay 3806, which is normal, contact 2 of relay 3801 which is actuated, conductor 3830, contact 5 of relay 5807, conductor 5830, contact 1 of relay 1804, contact 5 of relay 2801, contact 1 of relay 3801, contact 1 of relay 3805, conductor 3831, contact and armature of relay 2808, contact 2 of relay 2807, contact 4 of relay 6806 and earth.



   When operating, any relay in the series of forty relays, such as 3810 to 3813, opens the circuit for relay 2801 to prevent another similar relay from operating, should a junction preceding the entered junction become

  <Desc / Clms Page number 108>

 free after choosing the free junction. This obviously presupposes that the chosen free junction is found later in the series, that is to say that it is for example junction 10 or 15, instead of being the first junction, as we have chosen. for this link. By tripping, relay 2801 causes the armature of relay 2808 to move towards the. right.



   In operation, relay 3810 connects the conductors coming from the chosen free outgoing junction to the marker and also links a conductor coming from the selector electromagnet of the crossbar switch associated with this outgoing junction, to the marker, for example, the bar switch 1511. The closing of the circuits established by this link and the operation of the outgoing junction and of the associated switches will be repeated after a description of the operations, which occur in the marker, when no free junction is found in the marker. the group of tried junctions.



   Heavy traffic between some trunk offices may require the use of various trunk groups, each group comprising forty trunks. In the event that a free trunk is not found in a trunk group, another trunk group extending to the same remote trunk office is available and is therefore tried so that a free trunk in this trunk is found. second group of junctions can be obtained. The second group of junctions is associated with a second route relay and is under the control of the latter, this relay having to be actuated to associate the junction conductors with the test equipment of the marker.

   The following operations occur when the cross-bar switches for this second group of junctions are located on the same frame as the first group of junctions tested- Like all

  <Desc / Clms Page number 109>

 the junctions of a group were found to be busy and there are other junctions available in the same office, a chain circuit is established passing through the test relays of Fig. 38, lead 7045, the winding of relay 7011 to the battery, which circuit operates this relay. In operation, relay 7011 establishes an operating circuit for relay 6910, which circuit comprises: the battery, its winding, contact 3 of relay 6909, contact 5 of relay 7011, contact 4 of relay 6806, and earth.

   While operating, relay 6910 establishes a blocking circuit for itself, through conductor 2831, to ground through contact 2 of relay 7066 and through contacts of relay 7011. When operating, relay 6910 opens the circuit. blocking by relay 6909 which trips. While operating, relay 6910 again establishes an operating circuit for the junction occupancy relay 7006 through the contacts of the junction model relay 6915 to the battery, through the winding of the relay 7006, contact 1 of the relay 6909, contact 2 of relay 6910, contact 1 of relay 6908, contact 1 of relay 6907, contact 4 of relay 6806 to earth.

   In operation, the junction occupancy relay 7006 establishes a circuit to transfer the operating circuits and junction test circuits from the road relay 4702 to the road relay 4703 by the operation of a protective circuit apparatus. gression or circuit transfer apparatus, which transfers the conductors establishing the circuit from one route relay to another. To accomplish this transfer, the junction occupancy transfer relay 5906 is first actuated in a circuit comprising: earth, contact 4 of relay 7006, contact 14 of relay 4702, contact 11 of relay 5905, winding of relay 5906

  <Desc / Clms Page number 110>

 and the battery.

   While operating, the last relay locks to ground at contact 4 of relay 7006 and establishes an obvious circuit to operate relay 5937, from its 6 ground contact to contact 3 of relay 6806.



  A blocking circuit for relay 5907, passing through contact 5 of relay 5906 and contact 5 of relay 6002, is established, when relay 5906 trips, as will be described later. Relays 5906 and 5907 establish a circuit to operate the multiple contact relay 5905, which operates and thus opens all circuits previously established by the contacts of the road relays 4702, causes the relays which were actuated for the ES to trip. - sai previous and closes new circuits to transfer the junction test command to another 4703 road relay. The operating circuit of relay 5905 consists of the battery, ringing, contact 2 of relay 5907, contact 2 of relay relay 5906, relay 3606 contact 2, relay 6806 contact 3, and earth.

   The multiple contact relay 5905 is blocked, by its contact 17, by the contact 4 of the relay 5907 and by the contact 1 of the relay 6101, to the earth applied to the relay 6806. Since the operating circuit of the relay 5906 is established. through contact 11 of relay 5905, this relay 5906 now trips and, when tripping, opens the operating circuit of relay 5907, but establishes a latch circuit for relay 5907, through its contact 4, to the earth applied to relay 6806, as described above. Thus, relays 5905 and 5907 remain actuated and relay 5906 trips.

   When relay 5905 operates, the circuit of relays 3801 to 3805 is opened, returns to rest and thus opens the operating circuit of relay 7011 which, it will be remembered, operates, when all the junctions of the group have been found occupied, relay circuits

  <Desc / Clms Page number 111>

 Junction Model 6915 and Junction Busy Relay 7006 are also opened by tripping relay 5905.

   Relay 5905, when operating, and the junction occupancy relays, when tripping, now establish a circuit to operate the immediately next route relay, which selects another group of junctions to be tried. of the route relay 4703 is connected to contact 11 of the route relay 4702 and from then on, a circuit is established for the relay 4703 comprising the battery, its winding, contact 11 of the route relay 4702, which remains active, the contact 15 of relay 5905, contact 3 of relay 5906, which tripped, conductor 5947, contact 1 of relay 6104., conductor 5948, contact 6 of relay 6806 and earth.



   Progress from one route relay to another route relay in order to find a free junction to a particular trunk office has now been completed, the transfer being effected by activated relays, when all the junctions of the previous group are found occupied and also by the operation of relays 5906,5907 and 5905 and the subsequent tripping of relay 5906. Some control conductors coming from the recorder-sender and the circuits grounded previously described are thus transferred from the contacts of relay- 5905 to the contacts of relay 6001, which are now connected to the contacts of route relay 4703.



  Where there are a large number of junctions to a particular trunk office, use may be made of more route relays than shown, and the transfer from one route relay to another, as well as, consequently, from one group of junctions to another, each group being controlled by a route relay, is carried out

  <Desc / Clms Page number 112>

 in the manner described for the transfer from route relay 4702 to route relay 4703. If no free junction is found in the second group and a third route relay is used, relays 6002,6003 and 6001 are actuated in the manner described for relays 5906, 5907 and 5905, to effect the transfer of the control conductors, from the second route relay to a third route relay.

   A transfer to a new route relay, to test a different group of junctions which are part of a large group of junctions going to the same office, would normally establish circuits to operate the common marker apparatus. as previously described. The same turn-on circuit for a connector between the marker and the allocation frame can be employed, or in some cases a different turn-on circuit may be used. In this example, the same start circuit is connected to road relay 4703 and relay 4803 is energized again. This causes the selection of the same connector between the marker and the allocation frame, if this connector is not taken by another marker.

   If, however, it is taken by another marker, a sequence circuit is established in the manner described for the connector placed between the recorder-sender and the marker, and therefore use is made of. another connector, which operates in the same way as the connector previously described. The particular purpose of transferring from one route relay to another is to establish circuits to try a different block of outgoing junctions going to a particular trunk office and to designate the extent of that group of junctions by marking the starting point. and the termination point of the sub-group of junctions in the apparatus of FIG. 38.

   For this example, the marker group or terminal block relay 4903 is connected
AT /

  <Desc / Clms Page number 113>

 by jumper wire to contact 10 of road relay 4703 in the same way that the junction group relay 4902 was connected to contact 10 of road relay 4702. A circuit is thus established comprising: the battery, the coil the relay 4901, the winding of the relay 4903, the contact 10 of the road relay 4703, the contact 17 of the relay 6001 and earth.

   In operation, trunk group relay 4903 connects conductor 4922 to conductor 4923. Conductor 4922 is connected to the battery through contact 8 of relay 4903 as previously described.



  Conductor 4923, however, extends to a relay of a junction group different from the preceding one, since it is connected, through contact 6 of relay 4122, to earth by the winding of junction block relay 3115. , and associates the test conductors with a second group of trunks extending to the same trunk office. The rette relay 4703 is connected to the same category relays as the route relay 4702 since, in this example, the category does not change. Assume that the second group of junctions includes only 17 junctions and therefore the test for a free junction started at junction 0 and ended at junction 16.

   In order to mark the limit of the test, relay 3801 is connected to contact 3 of route relay 4703 and the seventeenth relay or relay 3803 is connected to contact 4 of route relay 4703. This naturally assumes that relay 3803 is the seventh relay in the series of forty relays. As was previously the case, the "intermediate" relay 6907 is actuated and the terminating trunk relay 6908 is normal, indicating that an intermediate outgoing trunk to a remote interurban office should be chosen. Thus, an earth is connected from contact 4 of relay 6806 by contact 1 of relay

  <Desc / Clms Page number 114>

 6907, contact 1 of relay 6908, contact 2 of relay 6910, the winding of relay 6909, to the battery, which operates the latter relay.

   This earth is also extended from contact 2 of relay 6910, by conductor 6921, contacts 3 and 4 of relay 6001, contacts 3 and 4 of road relay 4703, windings of relays 3801 and 3803 and relays 2806 and 2809 , to the battery. Relay 2806 is a warning relay for even numbered test relays, such as number zero relay 3801. Relay 2801 is a warning relay for odd numbered relays, such as number relay seventeen 3803. As will be explained, these relays associate the earth with a time counter circuit, which operates only after a certain time, allowing the maximum time to complete the test of a group of junctions.

   If the test of the junctions of a group is not carried out within this maximum period of time, the warning circuit and a fault circuit indicate that there is in the marker a fault of a nature such as the test of junctions cannot be completed. In this case, the marker is released and the recorder-sender enters another marker for a second attempt. The test leads coming from the outgoing junctions of this group are connected to the test relay in Fig. 38 in the manner previously described.



  To perform this test, the same relays are actuated by the terminal block relay as before, including relay 1801. The junction test circuit is connected by the series circuit extending through the contacts of relays 3801 to 3803, as well as the intermediate relays and by the contacts of relays 3806 to 3817, including the intermediate relays. When one of the relays 3806 to 3817 is found normal, this indicates that the numbered junction corresponding to the group is free, and, therefore-

  <Desc / Clms Page number 115>

 quence, that the circuit passing through the series of contacts terminates at this relay and is extended by the winding of the corresponding relays 3810 to 3818.

   In operation, a particular relay of the horizontal row 3810 to 3818 associates the conductors of junctions by the contacts, to carry out the seizure of the outgoing junction and to carry out a second test of the junction in order to ensure that this junction is in. state of linking.



   The extended circuit of contact 1 of relay 3806 by an associated series of contacts, when this relay and the associated relays of this horizontal row are found actuated (indicating that the associated junctions are busy) is the same circuit as that which operates relays 6810 to 6813, when a free junction is found. For simplicity of discussion, assume that junction zero is found free and that a circuit is established for relay 3810.

   This circuit includes: the battery, relay contact 4 of relay 7011, relay contact 3 of 7006, conductor 7043, the winding of relay 3810, contact 1 of relay 3806, which is normal, contact 2 of relay 3801 which is actuated, conductor 3830, contact 5 of relay 5807, conductor 5830, contact 1 of relay 1804, contact 5 of relay 2801, contact 1 of relay 3801, contact 1 of relay 3803, conductor 3831, the contact and armature of relay 2808, contact 2 of relay 2807, contact 4 of relay 6806 and earth.

   By operating relay 3810 establishes for itself a locking circuit comprising: the operating battery, contact 4 of relay 711, contact 3 of relay 7006, conductor 7043, winding of relay 3810, its contact 3, conductor 3856, contact 3 of relay 1707, conductor 1765, which is connected to conductor 1850, contact 4 of relay 6806 and earth. As previously described, relay 2808 operates

  <Desc / Clms Page number 116>

 starts in the opposite direction as soon as relay 3810 is actuated and, accordingly, relay 3810 remains actuated by the above-mentioned interlock circuit to ground at contact 4 of relay 6806.

   In operation, relay 3810 connects a conductor to its contact 1 from the free outgoing junction to operate the marker apparatus and to perform a second test of the junction, to ensure that another marker is not has not seized this junction during the time between the operation of relay 3810 and the seizure of the junction.

   This circuit from the free outgoing junction includes: the battery, the winding of relay 1610 of the typical outgoing trunk junction shown in Fig. 16, contact 1 of relay 1616, conductor 3126, a branch jack 3110 on the allocation frame, the neck or ring springs of this branch jack, the conductor 3125, contact 5 of the junction group relay 3116, contact 8 of the multiple contact connector relay 4122, the conductor 3125, contact 1 of relay 3810, conductor 3840, contact 7 of relay 6101, conductor 6140, the windings of relays 1705 and 1704 and a potentiometer, one branch of which extends through conductor 1743, contact 6 of relay 4001, resistor 4015 up to the battery,

   the other potentiometer branch extending through resistors 1717 and 1716, conductor 1760, contact 1 of relay 1740, conductor 1723, contact 3 of relay 5105, and 5106, to earth to contact 3 of relay 1902. The potentiometer ground circuit has a low resistance and establishes a circuit through relay 1703 and relay 1610 in the outgoing junction circuit. In operation, relay 1704 establishes a circuit to operate relay 1706, which establishes a lower resistance ground circuit for the potentiometer and also establishes other circuits.

  <Desc / Clms Page number 117>

 which will be described later. A blocking circuit for relay 1706 is later established by a contact of relay 1802.

   This latter relay is, however, not actuated until a coupling and connector circuit, as shown in Figs. 15, 25, and 26, has not been put into service.



   Recycling the marker.



   ---------------------
The polarity of relay 1705 is in the opposite direction to that of relay 1704, and relay 1705 only works if the sostante junction is entered by another marker between the time the 3810 relay is actuated and the time this marker attempts to switch. enter the junction.



  In this case, there is a double connection and a ground is connected to conductor 3126 of the outgoing junction (Fig. 16) by the first marker to grab the junction.



  A circuit is therefore established for relay 1705 to the battery on the battery branch of the potentiometer, as described. In operation, relay 1705 establishes a circuit, to operate relay 1717, from the earth applied to the contact of relay 1705, by conductor 1760, contact 4 of relay 4001, conductor 4043, contact 8 of relay 2801 and the winding of relay 1707 up to the battery. The relay 1707 has a latch circuit which is only established, if the relay is actuated, by a double connection, after the operation of the coupling and connector circuit (Figs. 15,25 and 26). This latch circuit also extends to ground on a contact of relay 1802.

   In operation, relay 1707 opens the latch circuit of relay 3810, since this latch circuit extends, as described, through contact 3 of relay 1707. Relay 3810 trips and opens, by tripping, the circuit established by its. contact 1 for relays 1704 and 1705, causing them to trip and the

  <Desc / Clms Page number 118>

 relays 1706 and 1707, since at this moment no locking circuit is established for these two last relays. This operation is known as the marker recycle operation, since after triggering relay 3810, the marker immediately re-establishes its test circuit, with a view to finding another free junction, the circuit being the same as previously described.

   Since the junction previously found free was entered by another marker, relay 3806 is actuated and when the double connection triggers relams 3810, the test circuit used to find a free junction is extended by contact 1 from relay 3806 to the armature of relay 3807 and then through the chain circuit from one relay to another, until a normal or unactuated relay is found, which indicates that the corresponding junction is free . When this free junction is found, the operations take place in the manner described above to actuate the relay of the lower horizontal row corresponding to relay 3810 associated with the relay of the following horizontal row which was found to be normal.



  The corresponding free junction is entered as previously described and a dual connection test is performed on this junction as described above.



   In trunk offices, there are many small trunk groups extending to small trunk centers, and therefore some trunk blocks or trunk groups may include trunk trunks having joint transmission characteristics, such as, for example, termination junctions that extend from one inter-city office to another and terminate in the second office

  <Desc / Clms Page number 119>

 toll, intermediate toll junctions used for links which extend beyond the next remote toll office and combined toll trunks which may be used either for intermediate service or for termination service.

   A group of such junctions can be given as an example of groups consisting of three subgroups, i.e. a subgroup of twelve termination junctions, a subgroup of eight intermediate junctions and a subgroup of fourteen junctions. is combined. The arrangement / such that if no free terminating junctions are found in the subgroup of terminating junctions, a transfer is automatically made to the subgroup of combined junctions.



  Likewise, if no free interconnecting junctions are found in a subgroup of intermediate junctions, a transfer is automatically performed to a subgroup of combined junctions, so that in one and in the other case, an attempt is made to find a free junction having the desired transmission characteristics. As an example of a trunk test in a group of this kind, it will be assumed that an incoming call requires an intermediate trunk, as in the previous example of incoming calls, and, therefore, that the "intermediate" relay 6907 is actuated.

   It will also be assumed that the route or feeder relay 4702 is arranged for this type of split group and that for this reason its contacts 1, 2, 3, 4, 5 and 6, are connected to the windings of some of the forty relays. 0 to 39, such as relays 3801 to 3805, in the following manner to mark the junctions of the start and end of each subgroup. Thus contact 1 of relay 4702 can be connected by jattie wire.

  <Desc / Clms Page number 120>

 re to zero relay 3801 of the horizontal row to control the start circuit for the test of the junctions of the subgroup of termination junctions. The second contact of relay 4702 can be connected to relay 11 of this horizontal row to control the end of the test of the termination junctions.

   Contact 3 can be connected to relay 12, contact 4 to relay 19 to control the start and end of the sub-group of intermediate junctions. Contact 5 can be connected to relay 20 and contact 6 to relay 33 to control the start and end of the sub-group of combined junctions. The connection of the contacts at the road relay 4702 to the windings of these relays is made in the manner shown for that which goes from contacts 5 and 6 of the relay 4702 to the windings of the relays 3801 and 3805 respectively. Since, as established here, relay 6907 is actuated, the earth applied to contact 4 of relay 6806 is associated, as before, by contact 1 of relay 6907 and contact 1 of relay 6908 to actuate relay 6909 and connect earth at the start and end points of the intermediate junctions subgroup.

   The free junction test is performed as described herein. If no free junction is available in the sub-group of intermediate junctions, a transfer is automatically carried out to the sub-group of combined junctions without taking place a transfer to another route relay. This is accomplished by the operation of relay 6905, which in this example can be assumed to be connected by jumper wire to contact 12 of road relay 4702 instead of relay 6915. As previously described, when it is not found in a group no free junction, relays 7011 and 7006 are actuated. This also applies to small subgroups when the relay contacts

  <Desc / Clms Page number 121>

 routes are connected as described.

   In the foregoing arrangement, these relays accomplish the transfer of conductors from one road relay to another, but in the present arrangement of small groups in a group of forty junctions, the transfer simply takes place of the trial run. a small test group from another small group, which transfer in this case will be from testing a subgroup of the intermediate junctions to the subgroup of the combined junctions. When relay 7011 is operating, earth is applied to contact 5 which extends through contact 3 of relay 6909, the winding of relay 6910 to operate the latter relay.

   In operation, this relay establishes a circuit to operate the combined junctions relay for the application of earth through the windings of the associated relays in FIG. 38, to mark the start and end points of combined seams as follows. While operating, relay 6910 opens the circuit of relay 6909, causing the relay to trip. A circuit is therefore established for relay 6901, from earth on contact 4 of relay 6806, by contact 1 of relay 6907, contact 1 of relay 6908, contact 2 of relay 5910? which is actuated, contact 1 of relay 6909 which has tripped, contact 2 of relay 6905, contact 4 of relay 6902, relay 6901, up to the battery, which operates the latter relay.

   The earth which operated relay 6901 is also extended to contacts 5 and 6 of relay 59J5 and contacts 5 and 6 of route relay 4702. The test of the combined junctions now continues as described above. - not for intermediate junctions, and it can be assumed that a free junction is found in that subgroup of junctions which is captured by the marker. When the call is intended for a trunk of the termination type,

  <Desc / Clms Page number 122>

 marker relay 7001 is actuated by a record from the sending recorder and previously actuated relay 7002 for an intermediate call remains normal. This establishes an operating circuit for relay 6908 to link to an outgoing terminating trunk.

   The earth intended to operate the "terriination" relay 6908 is extended by the loggers in the same way as before, by contact 5 of relay 4701, contact 4 of relay 4808, contact of relay 7002, contact 2 of relay 7001, and winding of relay 6908 to the battery. Thus, a ground is connected through contact 1 of relay 6907, contact 3 of relay 6908, contact 2 of relay 6904, and the coil of relay 6909 to the battery. This earth is also extended by contacts 1 and 2 of relays 5902 and 4702, to operate the relays marking the start and end of the sub-group of termination junctions.

   If no free junctions are found in the termination junction sub-group, relays 7011 and 7006 are actuated as before and a ground is connected from contact 5 of relay 7011 through contact 1 of relay 6903, and winding relay 6904 to the battery, operating the latter relay. When operating, relay 6904 triggers relay 6903 and thus connects earth to relay 6901 to activate relays to mark the test of the combined junctions. This earth can be connected by contact 3 of relay 6908, contact 2 of relay 6904, contact 3 of relay 6903, contact 1 of relay 6905, contact 4 of relay 6902, and the winding of relay 6901 to the drums .

   This same earth also extends to contacts 5 and 6 of relay 5905 and 4702 to operate the relays marking the start and end of the subgroup of combined junctions, and a test of the junctions of this subgroup is
AT

  <Desc / Clms Page number 123>

 then performed.



   Routing of incoming calls through the switch termination stream -------------------------------------- --------
Route relay 4801 is given as an exemplary arrangement for routing an incoming call through the switch termination train shown in Figs. 9 and 10. As previously established, the junction through which a call is to be extended through this train of switches, can be in the form of an intermediate trunk interjunction or an inter-city trunk trunk. termination. The representation making use of route relay 4801 is arranged to allow routing of a call from a terminating trunk to an office located in the area of the cross-bar switched trunk office.

   The 4801 route relay is actuated in the same manner as the other route relays, that is, from a circuit established by the recorder relay setting (Fig. 46 and the top of Fig. . 58). These relays operate a particular tens relay, such as relay 5908, and a particular fifties relay, such as 5909, which establishes a circuit for the road relay 4801, which includes: the battery, its winding, the contact of the relay 5909, relay contact 5908, contact 6 of logger relay 5802, contact 5 of logger relay 5801, contact 1 of logger relay 5804, contact 1 of logger relay 5803, contact 2 of relay 5805, contact 3 of relay 6803, contact 1 of relay 6805, and earth.



  In operation, relay 4801 associates the control conductors through the contacts of relay 5905 with the test apparatus of the junction of Fig. 38, and to the trunk group relay control gear, extending through the termination trunk assignment connector 5110.



  This terminating trunk assignment connector is

  <Desc / Clms Page number 124>

 the same as that shown in FIG. 41 and the terminal block or terminal group relays for the switch termination train are the same as shown in FIG. 31. They are however associated with the outgoing junctions going to the offices located in the area of this interurban office with cross-bar switches. These junctions which are shown in FIG. 11 of the drawing extend to various types of local offices as well as to tributary offices which may be located outside a flat rate zone, but are reached by a trunk switched trunk.

   This allocation frame and the terminal block relays have been shown schematically at 5110 so as not to reproduce the circuit arrangement and apparatus shown in detail in Figs. 41 and 31. The circuits established by this allocation frame towards the junction block relays, towards the outgoing junctions, are constituted in the same way as described for the circuits established by the apparatus of Figs.



  41 and 31. Contacts 1 and 2 of road relay 4801 establish the number of junctions to be tried by the circuit maker to operate relays, such as 3801, and 3805, in the marker. The circuit of relay 3801, marking the starting point of the test, extending through contact 1 of the route relay is the same as the circuit previously followed to establish a link through the interurban train. switches. The circuit of relay 3805, establishing the end point of the test is also the same as the circuit followed for this relay when a link was established by the intercity train of switches.



   As previously established, use has been made for this example of a terminating trunk interjunction and, accordingly, relay 7001 is actuated at the contacts of the recorder relay (Fig. 46 and part

  <Desc / Clms Page number 125>

 upper part of FIG. 58). Relay 7007 is normal. For this reason, a circuit is established for the relay of terminating junction 4908, and the relay of intermediate junction 4907 remains normal. The 4908 relay circuit consists of: the battery, its winding, contact 2 of relay 7001, contact 1 of relay 7002, contact 4 of relay 4808, contact 2 of relay 6806, and earth.

   When relay 6908 is actuated, a circuit can be followed for relays 3801 and 3805 comprising: earth, contact 4 of relay 6806, contact 1 of relay 6907, contact 3 of relay 6908, contact 2 of relay 6904, normal, contacts 1 and 2 of relay 5905, contacts 1 and 2 of road relay 4801 and the windings of relays 3801 and 3805. The circuit from the winding of relay 3801 is extended to the battery by winding of relay 2806, and the circuit of relay 3805 is extended to the battery by winding of relay 2809. Contact 4 of road relay 4801 is connected to the terminal block relay winding of marker 4905, for which a circuit is established including: battery, relay winding 4901, relay winding 4905 , contact 14 of relay 5905 and earth.

   In operation, relay 4905 establishes a circuit for a particular terminal block relay connected by the contacts of the allocation frame connector relays 5110 which are actuated until the start circuit is established.



   This starting circuit is established by contact 3 of road relay 4801 which energizes relay 4809 by a circuit comprising: earth, contact 13 of relay 5905, contact 3 of road relay 4801, the winding of the relay 4809, the coil of relay 4807, and the battery.



  While operating, relay 4809 establishes a circuit to choose a preferred connector between the marker and the

  <Desc / Clms Page number 126>

 junction allocation frame 5110. This circuit includes: the battery, resistor 1905, contact 7 of relay 1903, conductor 5121, contact 3 of relay 5101 which is actuated, contact 1 of relay 5102, which is normal , conductor 4820, contact 2 of relay 4809, conductor 4827, the winding of a marker preference relay the same as 4919 and ground, which marker preference relay is in the allocation connector of the termination junction 5110.

   In operation, the marker preference relay establishes a circuit for the multi-contact connector relay similar to relay 4122. In operation, this multi-contact relay associates a number of conductors between the marker and the relay relays. terminal block of the termination junction allocation frame. A circuit is now established to select a particular junction block relay through the contact of relay 4905.

   Lead 4922 extends from the battery through resistor 1906 and contact 8 of relay 1903 as previously followed to contact of relay 4905, thence through lead 4924, the connector's multi-contact relay to ground, by winding a trunk group relay, such as 3114 or 3116, but in the termination trunk assignment connector 5110. A trunk group extending through the switch termination train is thus associated with the marker for the test.

   The contacts remaining on route relay 4801 are similar to those previously described, contact 6 extending to category 3 terminal (Fig. 75) to actuate relay 7504 and contact 7 s' extending to the combination of route occupancy relays comprising the relays 7006 and 7011 previously described, which operate when all the junctions of a group are occupied. Each junction in the connected junction group

  <Desc / Clms Page number 127>

 to the termination train of switches to conductors extending to the trunk allocation frame as described for outgoing trunk junctions, such as conductors 3126 and 3127.

   Since a multi-contact relay was actuated in a connector of the allocation rack extending to the outgoing junctions of the switch termination train, all of the relays in FIG. 38 are connected by this multiple contact relay to the switchgear of the group of junctions and to the outgoing junctions of a group of junctions ending in this switch termination train, and are not connected to the junctions associated with the intercity train of switches. It is for this reason carried out a test by the contacts of the relays 3806 to 3809 in order to find a free junction in this group of outgoing junctions.



  This takes place in the same way as previously described to obtain a free junction in a group of junctions connected to the intercity train of switches. When a free junction is found one of the relays 3810 to 3813 is actuated corresponding to the number of the free junction, and a circuit is established by contact 1 of the actuated relay to connect the battery of the outgoing junction relay to the switchgear. The test (Fig. 17) as previously described, a double test of the junction being performed in the same manner as previously described, by the operation of relay 1705. After the free junction has been found, the multi-frequency signals are transmitted. as will be described with respect to multi-frequency signals.



   Junctions going to the call order table.



   -------------------------------------------------
Route relay 4804 (Fig. 48, where TTB stands for to terminal block relay) is given as an example of an arrangement for routing an incoming call through a terminating train of switches to the switchboard.

  <Desc / Clms Page number 128>

 order of calls. Calls are routed to a call order attendant during a period of high number of calls and all trunks to a particular office are found to be busy, and during which the cordless operator considers no trunks. free will only be available during the time allowed to maintain the apparatus containing the marker pending a free junction. The incoming call may have been initiated on any type of trunk entering the office.

   Route relay 4804 is operated in the same manner as other route relays, i.e. from a circuit established by setting the recorder relays (Fig. 46 and top of Fig. 46). 58), except that in addition to setting the call sign recorder keys, the cordless operator also sets key TX 3401. When activated, key 3401 establishes a circuit for relay TX 4701 which transfers the conductors of the recorders to a set of fifty relays different from that used for the connections with the interurban offices and the offices located in the air of the interurban center.

   The TX 4701 relay circuit is established as follows: the recorder-transmitter relay 5704 is first actuated by a circuit comprising: earth, conductor 5717, key contact TX3401, winding of the relay 5704 and the battery. When operating, relay 5704 associates earth through its contact 2 with conductor 7434 which extends through the contacts of connector relays 7304 (remember that SO .... S9 mark recorder-senders 0 ... ..9) and 7405 to conductor 7484 in the marker and the coil of relay 4701 to the battery. A circuit is therefore established by the contacts of the recorder relays, contact 4 of relay 4701 and the winding of the relay from fifty 5903 to the

  <Desc / Clms Page number 129>

 drums .

   The tens relay 5901 is also actuated by a combination of contacts in the register relays as previously described. A circuit is therefore established for road relay 4804 comprising: the battery, its winding, contact 1 of relay 5903, contact 1 of relay 5901, contact 5 of recorder relay 5804, contact 4 of logger relay 5801, contact 1 of logger relay 5802, contact 1 of logger relay 5803, contact 2 of relay 5805, contact 3 of relay 6803, contact 1 of relay 6805, and Earth .

   In operation, the road relay 4804 associates the control leads through the contacts of relay 6001 with the junction test apparatus of FIG. 38 and to the switchgear :: Trunk route relay control extending through Termination Trunk Allocation Connector 5110. This Termination Trunk Allocation Connector is the same as shown in Figure Fig. 41 and the terminal block or trunk group relays for the switch termination train, are the same as shown in FIG. 31. The trunk groups reached by this allocation frame and by the associated trunk block relays include the trunks going to the call order table and the information desk.

   These junctions are shown schematically in FIG. 11 of the drawings. The circuits established by the allocation frame to the terminal block relays are constituted as described, for the circuits established through the apparatus of Figs. 41 and 31.



   The 4804 road relay contacts 1 and 2 set the number of junctions to be tried by making circuits to operate relays such as 3801 to 3805. The circuit of relay 3801, marks the starting point of the test,

  <Desc / Clms Page number 130>

 and the circuit of relay 3805 or similar relay establishes the end point of the test. Since a terminating trunk inter-junction is employed, a circuit is established by the logger relays for relay 70. He which in this case is actuated, and therefore relay 7002 is normal, one or the other of these relays being activated for a call determining the type of the junction in use. For this reason, a circuit is established for the terminating junction relay 4908 and the intermediate junction relay 4907 remains normal.

   The circuit of relay 4908 consists of: the battery, its winding, contact 2 of relay 7001, contact 1 of relay 7002, contact 4 of relay 4808, contact 2 of relay 6806 and earth. When relay 6908 is actuated, a circuit can be followed to operate relays 3801, and 3805, from earth to contact 4 of relay 6806, through contact 1 of relay 6907, contact 3 of relay 6908, contact 2 of relay 6904, normal contacts 1 and 2 of relay 6001, contacts 1 and 2 of road relay 4804 up to the windings of relays 3801 and 3805.

   The circuit coming from the winding of relays 3801 is extended to the battery, by the winding of relay 2806 and the circuit of relay 3805 is extended from the battery by the winding of relay 2809. Contact 3 of the control relay route 4804 is connected to establish a start circuit extending through the winding of the start relay 4809, and contact 4 of the road relay is connected to a terminal block relay such as the switch relays. terminal block 4902, 4903, 4904 and 4905 and this circuit is closed in the same way as the circuits previously followed for these relays.



   The start circuit established by contact 3 of road relay 4804 energizes relay 4809 by a circuit.

  <Desc / Clms Page number 131>

 baked including: earth, relay 6001 contact 13, road relay contact 3, relay 4809 winding, relay 4807 winding and battery. In operation, relay 4809 establishes a circuit to choose a preferred connector between the marker and the 5110 junction allocation frame.

   This circuit includes: the battery, resistor 1905, contact 7 of relay 1903, conductor 5121, contact 3 of relay 5101 actuated and contact 1 of normal relay 5102, conductor 4820, contact 2 of relay 4809 , conductor 4827, the winding of a marker preference relay such as relay 4119 and ground, which marker preference relay is in termination junction supply connector 5110. In operation , the marker preference relay establishes a circuit for the connector multi-contact relay similar to relay 4122.

   This multi-contact relay, in operation, associates a number of conductors between the marker and the function block relays of the termination junction allocation rack. A circuit is now established to choose a particular terminal block relay, by the actuated terminal block relay contact to contact 4 of the 1-4804 route relay. This circuit is established like other circuits passing through the terminal block relays in which the battery is extended by conductor 4922, to the contact of the terminal block relay such as 4902, thence through a conductor (no shown), the connector's multi-contact relay and the winding of a terminal block relay or a terminal group such as 3114, in the 5110 terminating trunk assignment connector.

   A group of outgoing junctions going to the call order table is therefore associated with the marker for testing and the testing of these junctions is performed by the relay contacts such as 3806 to 3809 to find a free junction. to the call order table. As

  <Desc / Clms Page number 132>

 previously established, a relay such as 3806 to 3809 which is normal indicates that the junction of this number in the junction group is free and that therefore a circuit passing through the contacts of this normal relay is extended to the relay located below, like relays
3810 to 3813 inclusive. This circuit is extended by the winding of the relay of the lower horizontal row which causes the relay to operate in the manner previously described.

   In operation, this relay associates conductors coming from the junction and extending to the marker call order table in the same way as previously described for other outgoing junctions and the outgoing junction going to the table. order of calls can thus be entered after a double test made to determine whether it is free or occupied, test which is carried out by the apparatus of FIG. 17, as previously described.



   After the free junction has been found, multi-frequency signals are transmitted to the marker equipment to indicate to the marker the situation of the rack on which the crossbar switch connected to the calling incoming junction is placed and the rack number. on which is placed the crossbar switch which is connected to the outgoing junction going to the call order table.

   The operation of this apparatus in the marker designates the connector to be employed between the marker and the switches of the coupling to cause the operation of the secondary incoming cross-bar switches and the primary output cross-bar switches to establish a connection. channel between the primary incoming crossbar switches connected to the calling incoming junction and the secondary output crossbar switches

  <Desc / Clms Page number 133>

 connected to the junction of the call order table.



  A description of this link is given later for handling calls by both the inter-switch train and the switch termination train.



   Multi-frequency signaling system intercity train.



   -----------------------------------------------
In order for the marker to operate to operate the crossbar switches between a calling incoming junction and a chosen free outgoing junction to a particular office, which involves selecting a junction conductor lane between them, the number of the frames on which these junctions are located must be transmitted by signals to the marker and a signal must be given indicating whether the frame is even or odd.



  An intercity system should be particularly simple and for this reason the present intercity system with cross-bar switches is arranged to transfer groups of trunks to desired locations without in any way interfering with the operation of the intercity system and the communication. ability of the marker to locate the position of incoming junctions coming from particular offices or outgoing junctions going to particular offices - It can be seen that thanks to the appropriate frame number signaling system, a route relay actuated to choose an outgoing junction going to a particular office does not have to be associated with a particular rack for the system to operate efficiently.

   The number of the incoming frame on which the calling incoming junction is located is given to the marker shortly after the marker has been entered by the recorder-sender and the marker registers have been set to operate circuits. per-

  <Desc / Clms Page number 134>

 Putting to establish this frame number signaling circuit. It has been assumed, for this description, that the incoming junction is located on frame number zero which is an even number frame. Below is a description of the method by which the numbers of the crossbar switch frames are transmitted to the marker.



   Fig. 20 shows a multiple frequency transmitter comprising several current sources shown as generators 2072 to 2078 inclusive, each arranged to transmit current of a frequency which differs from that of the others. There is associated with each generator an adjustable amplifier as well as a transformer such as 2048 tuned to oscillate at a particular frequency as well as an output transformer such as 2040 to transmit current of this frequency to the number signaling circuit. built. The circuit structure of an amplifier 2001 is shown and the other amplifiers 2002 to 2007 inclusive which have the same circuit structure are shown schematically.

   There are resistances such as 2011 to 2036 inclusive specific to each signal conductor to distribute the load. A large number of different signals are required which equals the maximum number of toll office frames plus other signals intended for special uses. These are obtained by combining several current frequencies from different generator circuits for each transmitted signal. There are three mounted combinations for actuating corresponding receivers and combinations of equipment in a circuit receiving the marker.

   Conductor 2960 is shown as an example of a signal sending circuit extending to a switch on an incoming rack connected by three conductors to resistors 2011, 2016 and 2021, a current of different frequency.

  <Desc / Clms Page number 135>

 rent going through each of these resistances. A given number of generators and amplification circuits makes it possible to have a large number of combinations of three frequencies all having different combinations of frequencies. Ordinarily, eight generators and similar amplifying circuits provide a number of combinations sufficient for a large telephone office.



  In the example given here, the office contains forty frames of incoming junctions and forty frames of outgoing junctions. Special combinations of frequencies are employed for devices belonging to junctions where junctions are added to a normal group of junctions for temporary service when the adjuncts and normal junctions are located on different racks. This arrangement is known as the jump scan for special junctions which will be described in detail later. The three frequencies are transmitted over a single conductor, such as conductor 2060, to a transformer associated with the selector electromagnets of the crossbar switches of a frame.

   In this case, conductor 2060 has been connected by transformer 1401 which is associated with the selector electromagnets of the zero arrival frame. Each incoming rack has a similar conductor connected to a transformer, such as 1401, and a different combination of frequencies is transmitted through the primary winding of the transformer in each rack. Each rack can have any number of these transformers, all of the primary windings of these being in series with each other, connected by a conductor such as 2060 to the output of three generator and amplifier circuits, the windings secondary of these transformers being specific to the selector electromagnets of the different

  <Desc / Clms Page number 136>

 cross-bar switches on a frame.

   Such an arrangement can be used to distribute the load over several of these devices. A combination of three frequencies also runs through a single conductor going to the transformers associated with the selector electromagnets of the secondary cross-bar switches of the outgoing junctions, the frame being connected practically as illustrated in FIG. 15. A transformer 1517 is mounted, the primary winding of which is connected to the frequency generator circuit and the secondary winding of which is connected by the windings of the selector electromagnets 1509 and 1510.



   The multi-frequency signals of rack numbers are transmitted from selector electromagnets in particular racks to a receiver circuit shown in FIG. 27 of the marker. These signaling circuits coming from the particular frames are associated with the receiver circuit of FIG.



  27 by the apparatus of the marker actuated during the progressive sequence of operations in the marker to give the number of the arrival frame on which the calling junction is located and subsequently the number of the frame on which a free exit junction to a particular office is found. After each signal has been transmitted, the marker is again set for a next signal. Each combination of signals is transmitted through conductor 3540 to input transformer 2702 of the receiver circuit.



  The output winding of this transformer is associated with an amplifier circuit which includes tube 2701, the primary winding of transformer 2709 being in the plate circuit of this tube. The secondary winding of transformer 2709 is connected to a number of special receivers including the filter circuits

  <Desc / Clms Page number 137>

 2741 to 2748, inclusive. Each of the above filters is designed to pass a particular band of frequencies. Tuned transformers, such as 2714 or 2722 are connected by an adjustable resistor such as 2713 or 2721 to the filters, each transformer being tuned to operate its gate only at a particular frequency.

   The three frequencies transmitted for a signal from the frame therefore actuate three matched transformers associated with the particular filter circuits, each transformer creating a current in the gate circuit of an associated amplifier to actuate particular relays, such as as 2727 and 272, in the amplifier plate circuit. These frame signals therefore actuate a combination of three relays such as 2717 and 2725, which sets! circuits for actuating three of the relays shown in FIG. 37 at the bottom of FIG. 27. It is a well-known fact that it is difficult to create sufficient current in an amplifier circuit such as that shown in FIG. 27 to actuate relays of the kind shown in FIG. 37 and in the lower part of Fig. 27.

   Therefore, relays such as 2717 and 2725 are used to create individual circuits for relays which are heavily loaded with contacts. These relays 3701 to 3704 inclusive and 2729 to 2732 inclusive each have a large number of contacts by which different combinations of circuits can be established for the signals created by the multi-frequency transmission circuit. It is clear that these relays can be operated in combinations as numerous as the combinations of frequencies transmitted. The circuits established by these contacts actuate the marker equipment in various ways to control the operation of the marker.

  <Desc / Clms Page number 138>

 in order to associate it with the frames of a given number.



  * These circuits are established in such a way that the created result verifies the correctness of the transmitted signals.



   Indication of the interurban train arrival frame.



   ------------------------------------------------
The indication of the arrival frame is transmitted to the marker as follows:
The contact breaker relay indicating the number of the incoming frame 3501 is first actuated by a circuit which comprises: earth, contact 4 of relay 6807, conductor 6820, a chain of contacts comprising: the highest contacts of relays 3701, 2702, 3703, and 3704 and the lowest contacts of relays 2729,2730, 2731 and 2732, conductor 2740, contact 3 of relay 3504, the winding of the contactor relay 3501 and the drums .

   This circuit is extended by the contacts of relays 3701 to 3704 and 2729 to 2732 inclusive, in order to prevent the transmission of a multi-frequency signal if some of these relays are activated and are therefore not in a state to respond. current signaling. Relay 3501 operates and is locked by its contact 2 and contact 4 of relay 3504 by conductor 3545 which joins conductor 6820 extending to earth on contact 4 of relay 6807. Relay contactor 3501 can consist of a relay single or in several relays having a sufficient number of contacts to simultaneously connect the frame number signaling conductors coming from all the frames.

   However, the signaling conductor through which the signal of the frame number is transmitted is made individual to the particular frame on which the calling incoming junction is located, thanks to the connection of this signaling conductor with the marker, via the circuit of the calling incoming junction. For this reason, relay 3501 connects in

  <Desc / Clms Page number 139>

 operating the multi-frequency signaling circuit extending through the winding of the incoming primary selector electromagnet 1405 of the cross-bar switch connected to the calling incoming trunk interjunction (Figs. 12 and 13), to the primary winding of the input transformer 2702.

   This circuit comprises from its origin: the generator current transmitted from generators 1, 2 and 3, a: plified by the associated amplifier circuits, the output transformers 2040 and similar transformers of the second and third circuit frequency transmission as well as resistors 2011, 2016 and 2021 which are connected to the conductor 2060. The three frequencies are thus transmitted by the primary winding 1403 of the transformer 1401 and to the secondary winding 1402 by induction.

   From secondary winding 1402 frequencies are transmitted by the winding of the associated selector electromagnet 1405 of the crossbar switch connected to the incoming calling junction shown in Figs. 12 and 13. The circuit comprises: the selector electromagnet, the conductor 1453, the contact 7 of the relay 1213 actuated in the circuit of the incoming junction and the conductor 3229 extending through the coupling switches (Fig. 32). which were actuated to associate the incoming junction with the operator position without cords and with the recorder-sender associated with it.

   Conductor 3229 extends through contact 10 of coupling crossbar switches 3200 and 3203 to conductor 5501, through contact 7 of relay 5505, conductor 5501, contact 3 of recorder-sender relay 5601, conductor 7311, marker connector 7304 multi-contact relay contact 2, 7405 multi-contact relay contact 1, conductor

  <Desc / Clms Page number 140>

 tor 7471, relay 1707 contact 1, relay 1714 contact 3, conductor 1740, relay 7003 contact 5, conductor 7040, normal relay 3504 contact 1, relay 3501 contact 1, and conductor 3540, to input transformer 2702 of the multi-frequency signaling circuit.

   It will be noted that the circuit going to the transformer 2702 is in multiple with a circuit passing through the resistor 3506 and the shock coil 3505 towards the earthed battery, which serves only to reduce the resistance of the contacts. As established previously, the three frequencies transmitted by the tracked circuit to the transformer 2702 are amplified and transmitted to the filters 2741 to 2748 arranged to pass particular frequency bands. In the circuit described, the first three frequencies were used to indicate that the incoming junction is located on the incoming zero frame.



  Therefore, the first three wire circuits;, res are used to operate the devices indicating the number of the marker. The first and last amplifier circuits associated with the filters are shown. The intermediate circuits are the same as shown, one i.e. they each have / relays such as 2717, to establish working circuits, In this case the first three relays such as 2717, are actuated by frequencies transmitted by the filters 2741, 2742 and 2743. Each relay associates a ground by a conductor extending to the relays of FIG. 37 and the lower part of FIG. 27.

   In this case, the earth is associated with the conductors 2750, 2757 and 2756 to actuate the relays 3701, 3702 and 3703. Circuits are therefore established to actuate the frame relay 3902 in order to signal to the marker that the chosen junction

  <Desc / Clms Page number 141>

 is on frame number zero, and relay 2902 to signal the marker that the frame on which the junction is located is an even frame. Relay 2902 circuit includes: battery, its winding, conductor 2941, contact 3 of relay 3501, contact 3 of relay 3702, contact 2 of relay 3703, conductor 3710, contact 5 of relay 6807 and the earth.

   The marker has one relay, such as 3902, corresponding to each arrival frame and another relay which will be described later corresponding to each output frame. The circuit to operate relay 3902 corresponding to frame zero includes: the battery, contact 1 of relay 2907, resistor 2910, the winding of relay 3902, conductor 3962, contact 5 of relay 3501, contact 9 of relay 3703, contact 4 of relay 3702, contact 3 of relay 3701, contact 5 of relay 6807, and earth.

   After a free outgoing junction has been chosen, circuits are established to indicate the frame number on which the outgoing junction is located, but a blocking circuit must first be established for the inbound frame relay 3902, since the circuits are established by both the incoming and outgoing frame relay contacts to determine the operation of the coupling and connector circuits for the incoming and outgoing frames.

   The output frame coupling and connector circuit is shown in Figs. 15, 25 and 26, and is substantially the same as the incoming housing coupling and connector circuit shown schematically in FIG. 14 in 1420. The blocking circuit of the 3902 inlet frame relay. ' operates as a switching circuit for the multi-frequency system, so that prior to transmitting the multi-frequency frame number signal giving the frame number of the outgoing junction, the multi-frequency relays shown in Figs.

  <Desc / Clms Page number 142>

 



  27 and 28 can trigger. This blocking and tripping circuit arrangement is as follows: relay 3503 is first actuated from the battery by its winding, conductor 3621, contact 4 of relay 2905, contact 1 of relay 2902, contact 3 of relay 3902, conductor 3962, which was the operating circuit of relay 3902, extending through contact 5 of relay 3501, contact 9 of relay 3703, contact 4 of relay 3702, contact 3 of relay 3701, contact 5 of relay 6807 and earth. While operating, relay 3503 connects the earth of contact 1 of relay 6807, through conductor 6835, the armature and middle contacts of relay 3503, conductor 3547, contact 1 of relay 2902, contact 3 and l winding of relay 3902, resistor 2910, winding of relay 2907 and the battery.

   The traced circuit blocks relay 3902, and ground from the inside contact of 3503 establishes an obvious circuit for relay 3504. In operation, relay 3503 also establishes a blocking circuit for itself, which circuit comprises: battery, its winding, conductor '3621, contact 4 of relay 2905, conductor 3547, contact of relay 3503 , conductor 6835, contact 1 of relay 6807 and earth.



   A record has now been made in the marker containing the indication of the number of the incoming frame on which the crossbar switch connected to the calling incoming junction is located and the indication that the frame number is even. The device also functioned to block the recording device to await the location of the crossbar switch rack connected to the chosen free outgoing junction. At this time, an adjustment is made in the marker to prepare it to receive other signals.

  <Desc / Clms Page number 143>

 of the multi-frequency signaling system. It will be recalled that the blocking circuit of the incoming frame contact relay 3501 was established by its contact 2 and contact 4 of relay 3504.

   For this reason, relay 3504 now activates the trip of relay 3501 which disconnects the multi-frequency signaling circuit from conductor 3540 extending to transformer 2702. All of the apparatus of Figs. 27 and 37 actuated to establish the number of the arrival frame, are triggered.



   Multi-frequency circuit to indicate the frame number for the outgoing junction.



   -------------------------------------------------
A circuit path for operating the apparatus indicating the output frame number is prepared by tripping relays 3701, 3702 and 3703, operating relay 3504, and tripping relay 3501. It is now established a circuit for a contactor relay that has enough contacts to receive signals from any outgoing junction crossbar switch racks.

   For this contactor relay 3502, a circuit is established comprising: the battery; its winding, conductor 3548, contact 2 of relay 3605, contact 3 of relay 3508, contact 7 of relay 3501, contact 3 of relay 3504, conductor 2740, the lowest contacts of relays 2732, 2731, 2730 and 2729 and the highest contacts of relays 3704, 3703, 3702 and 3701, conductor 6820, contact 4 of relay 6807 and earth.

   It will be noted that the followed circuit extended through the contacts of the relays of FIG. 27 and FIG. 37 who. were checking the proper reset of the marker to receive the multi-frequency signal indicating the frame number on which the bar switch is located

  <Desc / Clms Page number 144>

 that is connected to the chosen free outgoing junction. Relay 3502 is blocked by its contact 2 and contact 4 of relay 3508, conductor 3545, which forms a branch of conductor 6820 extending to earth on contact 4 of relay 6807.

   For this example, there. It is assumed that the free outgoing junction chosen for this connection is the zero junction of a group of junctions located on the odd output frame number 39 and that therefore the corresponding frame relay in the marker will be actuated. by a combination of frequencies transmitted from the marker frequency signaling transmitter. The marker relay 3901 has been shown to represent the frame relay for frame 39 of the outgoing junction frames. In addition to the rack indication, other relays, 3903 and 3905 are actuated by the multi-frequency system to establish circuits in the marker that are necessary for its operation, when the free outgoing junction is on an odd rack. .



  For this reason, a combination of three frequencies is transmitted by the selector electromagnet of the outgoing junction crossbar switch to actuate the particular relays of FIG. 37 and the lower part of FIG. 27, which will establish series circuits passing through their contacts to actuate these relays.

   In this case, electric currents of frequencies generated by the generators 2076, 2077 and 2078 are employed in combination, amplified by the amplifiers which are associated with these 2004, 2005 and 2006, which are identical to those which are shown associated with the generator 2072. These three frequencies are transmitted by the resistors 2025, 2029 and 2033 which are connected to the conductor 2070 so that they are transmitted by this single conductor to the transformer 1517, which in this example

  <Desc / Clms Page number 145>

 is associated with frame number thirty-nine.

   The three frequencies are transmitted from the primary winding 1519 to the secondary winding 1518 of this transformer and are thus transmitted to the selector electromagnets of the secondary crossbar switch associated with the free outgoing junction which has been chosen for the connection. with the incoming junction, calling. In this example, this is outgoing trunk zero of the Intermediate Trunk Trunk Group. Winding 1518 is specific to the switch with which it is associated.

   These currents of different frequency are therefore transmitted by the winding of the selector electromagnet 1510, the conductor 3841, the connection jack 3110, the tip springs of this connection jack, the contact 2 of the terminal block relay 3116, allocation rack connector relay contact 9 4122, conductor 3841, to relay 3810 contact 2 which, it will be recalled, was actuated when free junction was selected.

   The circuit continues with conductor 3842, contact 4 of relay 1707, contact 2 of relay 1714, conductor 1752, contact 1 of relay 7003, conductor 7047, rear contact of relay 2904, conductor 2911 and to top conductor 2812, contact 7 of relay 2801, conductor 2813, contact 1 of relay 3502, conductor 3513, contact 4 of relay 3507, conductor 3514, contact 2 of relay 3504, conductor 3540 and the transformer 2702.

   The three frequencies transmitted by the circuit followed to control the signaling equipment of the frame pass through the filters 2745, 2746 and 2747 respectively, the bands of which pass the amplified currents coming from the generators 2076, 2077 and 2078, and excite the trans- trainers granted associated particular to these circuits-

  <Desc / Clms Page number 146>

 filters to activate the three associated relays similar to relay 2717.

   The three actuated relays connect the earth to conductors 2752, 2753 and 2754, to actuate the relays 2729, 2730 and 2731, which establish series circuits by their combined contacts to actuate the apparatus of the marker in order to finally establish telephone communications between an incoming trunk on the even frame of the incoming trunk switch and an outgoing trunk on an odd frame of the outgoing trunk switch.

   The outgoing junction frame relay 3901 is actuated from the battery by the coil of relay 2908, resistor 2909, coil of relay 3901, conductor 3963, contact 7 of relay 3502, conductor 3515, contact 9 of relay 2731, contact 4 of relay 2730, contact 4 of relay 2729, conductor 3710, contact 5 of relay 6807 and earth. A circuit is also established to indicate that the frame is an odd frame, by the operation of relays 3903 and 3905. The circuit of these relays includes: the battery, the windings of the two relays 3903 and 3905, the conductor 3960, the contact 4 of relay 3502, contact 4 of relay 2731, contact 1 of relay 2729, contact 1 of relay 2730, conductor 3710, contact 5 of relay 6807 and earth.

   At the same time, a blocking circuit is established for relays 3901, 3903 and 3905 as follows: when operating, relay 3901 associates its operating earth, from its internal contact 3 to its armature to actuate relay 2903, circuit which can be followed by earth by the upper armature, contact 2 of relay 3905, contact 4 of relay 2906, the winding of relay 2903 to the battery. Relay 2903 establishes a blocking circuit for relay 3901, which includes: earth, relay 6807 contact 5, conductor 3710

  <Desc / Clms Page number 147>

 contact 1 of relay 2801, contact 2 of relay 1801, contact 2 of relay 2903, contact 2 of relay 3905, armature 3 and winding of relay 3901, winding of relay 2908 and drums.

   The tracked circuit also connects earth through contact 2 of relay 2903 to operate relay 2904.



  It will also be noted that when operating, relay 2903 associates earth with armature 3 of relay 3905 as a blocking path for the two relays 3905 and 3903. When operating, relay 2904 opens the multi-frequency circuit followed by generators to transformer 2702, thus opening the operating circuit for the relays of the receiver circuit of the frame number of Figs. 27 and 37 which are now triggering. In operation, relay 2904 also establishes by its internal contact an energized circuit, for the selector electromagnet 1510 which is effective when the apparatus of Figs. 15, 25 and 26 has worked, which will be explained in connection with the description of the coupling and connector circuit shown in the aforementioned figures of the drawings.



   Multiple frequency verification circuit.



   ----------------------------------------------
It is clear that if an error should occur in the multi-frequency transmission system which would result in the transmission of more or less than three frequencies, inaccurate switching connections would result, if the marker does not. did not include a checking arrangement to guard against these errors. This verification arrangement includes special wiring of the series circuits passing through the relay contacts shown in FIG.



  37 and the lower part of FIG. 27, so

  <Desc / Clms Page number 148>

 that when less than three frequencies are transmitted, no circuit is established to continue the progressive operation of the marker, and therefore the marker cannot continue to operate to actuate the crossbar switches to establish the link . The marker is then released after a lapse of time which is measured by the time-counting circuit 5108 described above. When more than three frequencies are transmitted, the arrangement of the circuits in series passing through the contacts of the relays in FIG. 37 and in the lower part of FIG. 27 is such that several frame relays are actuated.

   For example, if this occurs during transmission of the incoming frame number indication, relay 3902 and another similar relay for a different frame would be actuated. Should this occur during transmission of the output frame number, relay 3901 and another similar relay will be actuated. Rack relays, such as 3902 and 3901, bypass the battery for operation through the windings of marginal bias relays 2907 and 2908, as previously followed for operation of rack relays.

   When a rack relay, such as 3901 or 3902 is operated from the battery by the 2907 or 2908 test relay winding, the resistance of the rack relay winding is large enough to prevent operation of these. check delay since the current is below the operating value. When more than one frame relay windings are multiple-associated by the 2907 or 2908 relay winding, the resistance is reduced and enough current is flowing through the test relay winding in use to cause its operation. .

   While operating, the check relay

  <Desc / Clms Page number 149>

 tion 2907 establishes an obvious circuit for relay 2905 which stalls at its operating ground. When operating, relay 2908 establishes a circuit to operate relay 2906 which locks at its operating ground. In operation, either relay 2905 or relay 2906 establishes a circuit to operate the main control relay 1902 from ground to contact 2 of either relay by winding relay 1902 to the ground. drums .

   While operating, relay 1902 opens at its contact 1, the control circuit for the allocation frame terminal block relays, such as 3116, which are actuated by conductors 4922, 4921, and 4923 extending through the contacts. marker terminal block relays 4902, 4903, 4904, and 4905 that are associated with particular route relays.



  Also by opening its contact 3, relay 1903 removes ground from the control circuit to operate the coupling and connector circuits shown in Figs. 15, 25 and 26 of the drawings and the operating circuits for the inbound connector and coupling circuits shown in FIG. 14. (note that in Fig. 14, 0F denotes an odd frame and MKR the marker).



  The operation of the marker is thus blocked, and no error occurs in the telephone communications. A signal is sent to the recorder-sender for a second try as described. This marker is therefore released, and the register-sender and the calling incoming trunk are subsequently associated with a different marker which establishes the link.



   Multi-frequency system for junction groups with jump exploration.



   -----------------------------------------------
It is assigned to the groups of interurban junctions going to the various interurban centers of the normal positions or situations on the various frames of

  <Desc / Clms Page number 150>

 switches and on the allocation rack where the service jacks are located, with additional space allocated on these racks being provided for an assumed normal expansion of the installation. These branch jacks are in particular intended to expand groups of trunk junctions when the opportunity arises either as a result of temporary special requirements or as a result of unforeseen additional requirements.

   In the case of special needs, larger trunk groups may be added to the normal trunk groups extending to a particular office, if trunks are rerouted through another long distance office to the long distance office in which this exceptional need is met. introduces himself.



  In other cases, junctions are added for permanent use between two long distance offices. In the event of an unforeseen increase or special necessities, it is sometimes impossible to immediately place the adjoining junctions on the same frame as the junctions originally installed between the two offices, and for this reason, a temporary arrangement by means of which the junctions originally installed between offices can be tried to obtain a free junction and, if there is no free junction in this group of trunk junctions, another group of junctions located on a A different frame, known herein as the hop-scan trunk group, can be tried to find a free trunk extending to this long distance office.



   In the previous description, a free outgoing trunk junction was found, in the normal group of outgoing trunk junctions reached by route relays 4702 and 4703. The term group

  <Desc / Clms Page number 151>

 normal will be applied here to groups of interurban junctions which can be reached from the primitive route given to the marker and which are located on the same frame of outgoing trunk switches.

   As previously described, the junctions associated with the route relay 4702 were first tried and since no free junction was found in this group, a second route relay 4703 was actuated BAR the route relay contacts 4702, so that a second successive group of junctions located on the same frame and extending to the same trunk office can be tried to find a free junction. It will now be assumed that the normal junction groups reached by route relays 4702 and 4703 were all occupied and that an assistant junction group is available through the jump exploration process.

   Assume also that the adjoining junctions are on a different switch rack than the junctions that could be reached by road lines 4702 and 4703, and that a third road relay not located directly below the Route relay control 4703 must be actuated in order for the adjoining junctions to be reached. It will be apparent from the above description that in order to indicate a frame number to the marker one must use a combination of multi-frequency circuits which constitutes a particular combination of circuits in the marker.

   Circuit arrangements are also necessary to prevent false maneuvers from establishing a link between the calling incoming junction and the outgoing junction of the adjoining group located on a different frame. In the illustration, route relay 4702 is intended to append trunk junctions to what may be assumed to be a normal group or subgroup of terminating, intermediate or combined junctions.

   Since in the description

  <Desc / Clms Page number 152>

 above it has been assumed that this was a call on an intermediate trunk, it will also be assumed in this case that the route relay 4802 is used to add a group of junctions to a group of intermediate junctions or to a group of combined junctions which can be used as intermediate junctions.



   It is shown in FIG. 31 an assembly by which one adds a group of junctions with exploration by jump to a normal group of junctions. In this figure, ITJ leads to intermediate junctions in the hop search groups and ITR goes to intermediate junctions of regular junctions. The connection cord 3130 with the fibers which are associated with it is connected between the exploration jack by jump 3104 and the last connection jack of a normal group of junctions. For this description, it can be assumed that this junction is junction number thirty-nine associated with route relay 4703 and that the normal group consists of forty junctions, zero to thirty-nine associated with route relay 4702 and thirty-nine. zero to thirty-eight junctions associated with relay 4703.

   The fortieth normal junction position is used for exploration by jump to the assistant group and is shown here as being the junction associated with branch jack 3108. Note in the drawing that two other taps of the normal group associated with the route relay 4703 are connected to branch jacks 3110 and 3109, 3110 being the first normal junction of this group and 3109 being an intermediate junction of the group. Since the 3130 patch cord plug is inserted into the 3108 jack, the last junction of the normal group is not available for use since the contacts extending to the last outgoing junction are opened by inserting. of the

  <Desc / Clms Page number 153>

 plug .

   Insertion of this patch cord into jacks 3108 and 3104 associates the test and operating leads of the marker with the jump scanning apparatus shown in the left part of FIG. 31. The outgoing trunk line can be disconnected from the jack and connected elsewhere. The first and last outgoing trunk trunks of the hop scan trunk group are shown schematically at 3134 and 3133 associated with relay 3107 and associated with conductors 3125 and 3136 extending to marker test relays in FIG. 38. The intermediate trunk junctions of this hop-scan group are also connected to the windings of relay 3107 as shown by the multiple jumpers.

   Two normal outgoing junctions have been shown in order to be able to describe the circuit arrangement adequately. 1A outgoing trunk density of FIG. 16 is associated with branch jack 3110 and an outgoing junction 3131 is schematically shown associated with branch jack 3109. In each case, it can be assumed that the outgoing junctions 3131, 3133 and 3134 are of the same type as the outgoing junctions. shown in Fig. 16 and "that they have the same circuit arrangement and the same apparatus. In each case these junctions are shown in the free state.

   If a junction is occupied the earth will not be associated with the socket of the connection jack, and the battery will not be associated by the relay with the neck conductor of the jack which, as we have noticed, extends towards the marker in order to try the busy and free junctions. Therefore, as long as there are free junctions in the normal group of junctions, the earth is associated by the socket conductor of one of the branch jacks..ient and wind it-

  <Desc / Clms Page number 154>

 ment of relay 1108 in the overflow or discharge circuit. This relay placed in the discharge circuit is used to prevent a calling incoming junction from being routed to the discharge if there are free junctions available.

   Earth from any free junction in the normal group also extends through the socket of the 3130 service cord; the socket of the jump scan jack 3104, and the bottom coil of the scan relay through jump 3106. In the group of jump scan junctions, the ground is also extended from any free junction by a special jump scan relay winding 3107 which activates relay 3107. This associates the ground in the circuit. which has just been followed to the inverter winding of relay 3106. As long as there are free junctions available in the normal group, relay 3106 does not operate since the earth previously followed from free junctions in the normal group. the normal group bypasses the lower winding of relay 3106.

   However, when all the junctions of the normal group are occupied, it is not associated with earth to relay 3106 and for this reason it operates by a circuit comprising: the battery, the winding of the discharge relay 1108, the 3108 jack socket, 3130 patch cord, 3104 jump scan jack, 3106 relay bottom coil, 3107 relay contact, and ground. Thus the group of jump exploration junctions are made available for use when earth is removed from the neck conductor extending to the marker. This land is used as a false occupation to tell the marker that the jump scan control junction 39 is occupied whenever there are free junctions available in the normal junction group.

   The marker finds the

  <Desc / Clms Page number 155>

 junction 39 in the free state when all the junctions of the normal group are occupied and, for this reason, seizes this junction in the same way that he would enter any free junction by activating the relay 3813 which associates the circuit of the marker to the exploration circuit by jump of the upper left part of FIG. 31.



  The operating circuit of relay 3813 is the same as the circuit followed for relay 3810 which includes: battery, conductor 7043, winding of relay 3813, contact 1 of relay 3809, normal, a series of contacts on the relays 3808, 3817, 3807 and 3806 which each are associated with occupied junctions and are therefore actuated, contact 2 of relay 3801, conductor 3830 and earth.



   While operating, relay 3813 establishes the following circuit, prepares the marker to release the apparatus associated with the normal group of junctions, so that the circuits can be rearranged for association with the group of exploration junctions. by jump. This circuit includes:

   the battery, a shock coil 3602, resistor 3603, contact 8 of relay 3601, conductor 3622, which forms a branch of conductor 2911, rear contact of relay 2904, conductor 7047, contact 1 of relay 7003 , conductor 1752, contact 2 of relay 1714, contact 4 of relay 1707, conductor 3842, contact 2 of relay 3813 which was actuated, conductor 3837, contact 10 of connector relay allocation 4110, 3114 terminal block relay contact 4, 3108 jack tip, 3130 branch cord tip conductor, 3104 jack tip, 3106 relay top coil,

   winding relay 3105, multi-frequency coil 3103, and ground. The established circuit also extends from

  <Desc / Clms Page number 156>

 the multi-frequency coil by the circuit followed to the rear contact of relay 2904, conductor 2911, forming a branch to conductor 2812, contact 7 of relay 2801, conductor 2813, contact 1 of relay 3502 which is actuated, the conductor 3513, relay 3507 contact 4, conductor 3514, relay 3504 contact 2, conductor 3540, to multi-frequency transformer 2702. Relay 3105 does not operate in the tracked circuit due to high strength 3603.

   Three frequencies are transmitted from the frequency generator circuit through the rear contact of relay 3105, and coil 3102, inductively transmitted to coil 3103, through the circuit followed by transformer 2702. A special combination of frequencies is transmitted to For this purpose, generators 2074 and 2077 for the amplifier circuits associated with them 2003, 2005 and 2006, the resistors 2024, 2028 and 2031, the conductor 2081, the rear contact of the relay 3105, the winding of the transformer 3102 by induction to the winding of transformer 3103, then by the circuit followed to transformer 2702.

   The three transmitted frequencies extend through the die circuits 2743, 2745 and 2746 to actuate the associated tuned transformers which are the same as 2714. An electric current is thus established in the associated plate circuits of the associated tubes, such as 2716. , to actuate relays such as 2717. The contacts of these relays associate the earth with the conductors 2756, 2764 and 2753 to actuate the relays 3703, 2729 and 2730.

   While operating, these last three relays establish a circuit by their contacts to actuate the exploration relay by jump 3507 of the earth by the contact 5 of the relay 6807, the conductor 3710, the contact 4 of the relay 2729, the contact 4 of the relay

  <Desc / Clms Page number 157>

 2730, contact 7 of relay 3703, conductor 3711, contact 5 of relay 3502, contact 1 of relay 3606, the right winding of relay 3507, conductor 3516, resistor 2909 and the winding of the relay. relay 2908 up to the battery. Relay 3507 is blocked by its contact 3, conductor 3517, contact 6 of relay 6102, conductor 6105, and contact 5 of relay 6806 to earth. This same earth extends through contact 8 of relay 3507 to actuate relay 3508.

   Relay 3502 trips. now since this relay was blocked at contact 4 of relay 3508. While operating, relay 3502 opens the special frequency indicator circuit established by its contact to indicate to the marker that a group of skip exploration junctions should be tried. In the circuit previously followed by the winding of the jump scan relay 3105, it will be remembered that resistor 3603 was included in the circuit.



  This resistance is high enough to prevent operation of relay 3105, so that the special frequency can be transmitted through its rear contact.



  When operating, however, relay 3507 removes resistor 3603 from the circuit followed by the winding of relay 3105, bypassing resistor 3603 through its contact 2. Relay 3105 is now operating to transmit another frequency to select one. road relay. which will be used for testing this particular group of assistant junctions. The group of three transmitted frequencies is one of many combinations of frequencies which are transmitted according to the route relay employed to reach a group of junctions appended to any particular normal group of junctions.



  As will be seen, from the circuits which are followed, the route relay actuated according to the transmitted frequency is controlled by the primitive routing for selection.

  <Desc / Clms Page number 158>

 from an outgoing junction to a particular office.



   In preparing to select a jump scan route relay, the 6101 jump scan ground relay is operated by a circuit comprising: the battery, its winding, relay contact 3 6103, conductor 6107, contact 2 of relay 3508, conductor 3517, contact 2 of relay 6807, and earth. A relay is now actuated to connect a combination of frequencies to indicate which route relay to use.

   This relay 3605 is actuated by a circuit comprising: the battery, its winding, contact 8 of relay 3502, contact 1 of relay 3601, contact 3 of relay 3508, contact 7 of relay 3501, contact 3 of relay 3504 , conductor 2740, the lowest contact 2731 of relays 2732, / 2730 and 2729, the highest contacts of relays 3704, 3703,3702 and 3701, contact 4 of relay 6807 and earth. Relay 3605 is blocked by its contact 4, contact 6 of relay 3601, contact 9 of relay 3507, conductor 3545, to earth on contact 4 of relay 6807.



   A combination of frequencies is now transmitted by the contact of relay 3605 as follows: the generators 2072, 2076, and 2077 provide the frequencies which are transmitted by the amplifiers which are respectively associated with them, the resistors 2015, 2026 and 2030, conductor 2082, inside contact of relay 3105, transformer winding 3102 to ground.



  This combination of frequencies is transmitted through transformer winding 3103, relay winding 3105, and relay top winding 3106 in multiple with capacitor 3117, the tip of jack 3104, the tip of the jack. connection cord 3130, the tip of the jack 3108, the contact 4 of the relay 3114, the contact 10 of the

  <Desc / Clms Page number 159>

 relay 4110, conductor 3837, relay contact 2
3813, conductor 3842, contact 4 of relay 1707, contact 2 of relay 1714, conductor 1752, contact 1 of relay 7003, conductor 7047, armature of relay 2904, conductor 2911 which forms a branch - ment of driver 362:

   which in turn forms a branch of conductor 3623, contact 11 of relay 6101, conductor 6169, contact 3 of relay 3605, contact
2 of relay 3601, contact 5 of relay 3507; the contact
2 from relay 3504, conductor 3540 to transformer
2702. In this case the frequencies are transmitted by the filters 2741, the tips 2745 and 2746, to their respective tuned transformers which actuate the associated relays such as 2717, energizing the plate circuit of the associated tubes. Earth is thus connected to conductors 2758, 2754 and 2753 to energize the relays
3701, 2729 and 2730 respectively.

   A circuit is established by the energized relay contacts to operate the jump scan route relay 4802, which includes: battery, coil 4802 relay, conductor 4824, contact 17 of relay 3605 , contact 8 of relay 3701, contact 4 of relay
2730, contact 4 of relay 2729, conductor 3710, contact 5 of relay 6807, and earth. While operating, the road relay 4802 extends the operating ground for that relay through its contact 8, conductor 4825, the coil of relay 3606 to the battery. While operating, relay 3606 connects this earth through the inner spring of contact 3 to conductor 3625 to operate relay 3601.

   A blocking earth is now established for relay 3606 and for road relay 4802 to prevent tripping of these relays when the operating earth is removed by the trip.

  <Desc / Clms Page number 160>

 of relays 3701, 2930 and 2729. The blocking circuit comprises: the battery, the winding and contact 8 of the road relay 4802, the driver 4825 and contact 3 of the relay 3606 and the battery, the winding and the contact 3 of relay 3606, conductor 3517, contact 6 of relay 6102, conductor 6105, contact 5 of relay 6806 and earth. Relay 3605 now trips since its blocking earth was extended by contact 6 of relay 3601.

   The relays 3606 and 3601 when operating, and the relay 3605, when tripping, open the frequency transmission circuit to the transformer 2702 and thus cause the relays of FIGS to be tripped.



  27 and 37, and establish an operating circuit for the relays 6104 and an operating circuit for the outgoing junction frame number signal contact relay 3502. The operating circuit of relay 6104 extends from the battery through its winding and contact 5 of relay 3601 to earth. The operating circuit for the signal contact relay 3502 includes: the battery, its winding, the conductor 3548, the contact 2 of the relay 3605, the contact 1 of the relay 3601, the contact 3 of the relay 3508, the contact 7 of the relay. relay 3501, contact-3 of relay 3504, conductor 2740, lower contacts of relays 3732, 2731, 2730 and 2729, upper contacts of relays 3704, 3703, 3702 and 3701, contact 4 of relay 6807 and Earth .

   In operation, relay 3502 allows a combination of frequency signals to be transmitted to provide the frame number on which the group of jump scan junctions is located after the next series of operations that cause the jump. transfer of the control conductors from the 4703 route relay for the normal junction group to the 4602 route for the jump exploration group.

  <Desc / Clms Page number 161>

 



   The busy junction relay 7006 is first activated by a circuit comprising: the battery, its coil, the conductor 7046, the contact 12 of the relay
6101, conductors 6111, contact 4 of relay 3601, conductor 3627, forming a branch of the conductor
2831, contact 1 of relay 1801 which was kept actuated by the allocation frame relay, conductor 1815, contact 4 of relay 6806 and earth. Relay 7006 is blocked to earth by the contact of relay 1801 and conductor 2831.

   The circuit of relay 3813 which was actuated in order to obtain access to the exploration group by skipping outgoing trunk junctions, extends through contact 3 of relay 7006 to the battery on contact 4 of relay 7011 and the relay 7006, by functioning thus causes the relay 3813 to be triggered. When functioning, the relay 7006 establishes an operating circuit for the relay 6002 which comprises: the battery, the winding of the relay 6002, the contact 15 of the relay 6001, contact 14 of road relay 4703, contact 4 of relay 7006 and earth. Relay 6002 locks at contact 4 of relay 7006 and opens the blocking circuit established earlier for relay 5907.

   The relay 6002 also establishes, while functioning, an operating circuit for the relay 6003, which comprises: the battery, the winding of the latter relay, the contact 6 of the relay 6002, the contact 1 of the relay 5907, the contact 3 of relay 6806, and earth. A circuit is established for relay 6103, from the battery through its winding, contact 7 of relay 6002, contact 2 of relay 3508, conductor 3522, contact 2 of relay 6807 and earth. A locking circuit is established by the left winding of relay 6103, also by its contact 2 towards the operating earth.

  <Desc / Clms Page number 162>

 by the circuit followed above.

   A circuit is established to operate relay 6001 from the battery by its winding, contact 2 of relay 6003, contact 2 of relay 6002, contact 1 of relay 6103, and contact 3 of relay 6806 to Earth . When operating, relay 6001 connects the ground control circuits through its contacts to the contacts of the jump scan route relay 4802. Operation of the ground relay 6001 renders the contacts of the original route relays ineffective. . The allocation frame relay, the category relay, the junction search relay, the junction model relays, the group start and end relays of Fig. 38 are all triggered.

   Triggering of the allocation rack relay is followed by tripping of marker preference and multiple contact relays 4119 and 4122 and also relay 1801. On tripping, relay 4803 and 4903 trips connector relay d. 'allocation 4122 and marker preference relay 4119 as well as junction group relay 3116. Since the blocking circuit for junction occupancy relay 70 () 6 passing through the contact of relay 1801, relay 7006 trips when relay 1801 trips, relay 7006 opens, tripping, the blocking circuit of relay 6002 which opens the blocking circuit of relay 6101.

   On triggering, relay 6101 makes the jump scan route relay 4802 effective in establishing circuits in the marker.



   The group start and end relays are actuated by contact 1 and contact 2 of road relay 4802 from earth to relay contacts 6101 to the battery by the windings of relays 3801 and 3805 if it is assumed that this group of exploration of rush-

  <Desc / Clms Page number 163>

 tions is a group of 40 junctions. This group of jump scan junctions can be of any graininess, and the group start and end conductors from contacts 1 and 2 of group relay 4802 are connected correspondingly. As an example, if the group has 18 junctions, the group start conductor can be connected to relay zero and the group end conductor connected to relay no.

   The category relay via contact 3 of route relay 4802 is connected as before since the category will be the same. The start conductor passing through contact 5 of road relay 4802 establishes a / circuit for the start relay of assignment connector 4806. The circuit passing through contact 4 of the drive relay 4802 establishes a circuit for. operate the 4904 terminal block marker relay. The 4806 relay circuit consists of: battery, 4807 relay winding, 4806 relay winding, 4802 relay contact 5, 6101 relay contact 2, and the earth.

   This establishes a circuit for the relay preferably of the earth marker 4107, through contact 3 of relay 4109, contact 3 of relay 4108, coil of relay 4107, conductor 4132, contact 2 of relay 4806, conductor 4820, contact 1 of relay 5102, which is normal, contact 3 of relay 5101 which is actuated since the recorder-sender associated with the marker is an odd recorder-sender, conductor 5121, contact 9 of relay 1903, and resistance 1905, to the battery. While operating, relay 4107 actuates multiple contact relay 4110 and relay 1801.



  The circuit to operate relay 4110 is obvious and should not be followed. The circuit to operate relay 1801 includes: earth,

  <Desc / Clms Page number 164>

 contact 2 of relay 4107, conductor 4130, coil of relay 1301 and the battery. A ground is also associated with this conductor outside of the operation of relay 4110, which is effective during the return to quiescent of the circuit. The connector terminal block relay is now actuated by multi-contact relay contact 4110.

   The circuit consists of: earth, coil of relay 3114, contact 5 of relay 4110, conductor 4925, contact 1 of relay 4904, contact 2 of relay 4903, contact 2 of relay 4902, conductor 4922, contact 1 of relay 2610, contact 1 of relay 1902, contact 8 of relay 1903, resistor 1906 and the battery.



   In order to make the example given here, of electing a free junction as simple as possible, we will again make use of junction n 0. The test apparatus for this free junction is represented by relays 3806 and 3810. Relay 3806 is normal in this case and, for this reason, a circuit is established by its currents to actuate relay 3810 as previously followed. A circuit is also established passing through the apparatus of Fig. 17 as previously described to test the chosen free junction in order to verify whether it has not been chosen by another marker during the establishment of the circuit. between this marker and the apparatus of the outgoing junction.

   For this example, free junction 0 of the hop scan junction group is found on outgoing junction rack # 3 and a combination of multiple frequencies is transmitted to the marker accordingly to actuate rack relay # 3. The frequencies used to indicate the frame

  <Desc / Clms Page number 165>

 n 3 are transmitted from the generators 2073, 2076 and 2077 by the respective amplifier circuits associated with them and by the resistors 2019, 2027 and 2032 by the conductor 2083 and by a transformer similar to 1517 connected to the selector electromagnet of the cross-bar switch of joncti.on 0 of the group located on frame n 3 in the same way as described for the electromagnet electromagnet 1510 which was located on frame 39 from the electromagnet associated with this junction,

   the circuit extends to the conductor 3137 as in FIG. 31 shows associated with the first junction of the exploration group by jump, from there by the contact
Junction Group Relay 2 3114, Multiple Contact Assignment Frame Connector Relay 4110 Contact 9, Conductor 3841, Relay 3810 Contact 2, Conductor 3842, Relay Contact 4
1707, contact 2 of relay 1714, conductor 1752, contact 1 of relay 7003, conductor 7047, rear contact of relay 2904, conductor 2911 which forms a branch of conductor 2812, contact 7 of relay 2801, conductor 2813, contact 1 of relay 3502, conductor 3513, contact 4 of relay
3507, driver 3514,

   contact 2 of relay 3504, and conductor 3540 to transformer 2702. In this case, the three frequencies are transmitted by the filters 2742, 2745 and 2746 to excite the tuned transformers which are associated with them and to energize the three associated relays, similar to the relays 2717. This associates the earth with the conductors 2757, 2754. and 2753 to operate relays 3702, 2729 and 2730.

   A circuit is established by the contacts of these relays to control the frame relay, which circuit comprises: the battery, the upper winding of the test relay 2908, the resistor 2909, the conductor 3516, the winding

  <Desc / Clms Page number 166>

 frame relay no.3 3911, conductor 3968, contact 6 'of relay 3502, contact 9 of relay 3502, contact 4 of relay 2730, contact 4 of relay 2729, conductor 2710, contact 5 relay 6807 and earth.

   The number of the frame on which the free outgoing junction of the jumping exploration group is located, which has been chosen, is for this reason given to the marker and it is further reported to the marker by the same combination of relays of Fig. . 37 and the lower part of FIG. 27, that the frame on which the junction was found is an odd frame. The circuit established for this purpose is the same as previously described need not be described again with regard to frame 3 since this is an odd frame. The circuit combination for an even output frame is similar and the circuit for establishing the contacts and circuits to indicate that it is an even frame has been given as part of the description of the selection of d. 'a free junction in the normal junction group.

   The circuits for establishing a link between the calling incoming junction on rack 0 of the inbound junction rack and an outgoing junction of the special group of jump-scan junctions on frame 3 can now proceed in the usual manner. Optionally, you can have a second group of jump scan junctions to the same desktop, so that if there is no free junction in the first group of jump scan junctions, the marker can continue. establishing a link by choosing the second group of hop-on exploration junctions as described for choosing the first group.

   In this case, the junction occupancy relay 7006 is again actuated as previously described, to abandon the first group of exploration junctions by jump and to pass,

  <Desc / Clms Page number 167>

 to the neighboring group of jump exploration junctions.



   If a second group of junctions is not available, the marker can link to a discharge junction or to the main busy circuit as described later.



   Multiple frequency signal switch termination train.



   ----------------------------------------------
The switch termination train has the same numbers as the trunk switch train and is made up of a number of even and odd frames. Route relay 4801 was actuated to select a free outgoing trunk connected to a secondary output switch located on an output termination frame. This route relay was actuated in response to an incoming call on one of the various incoming junctions shown on sheet 21.

   In response to this incoming call, a coupling is / actuated to associate the incoming trunk, either directly, to an incoming recorder-sender such as 2214 or 2215 or to a cordless attendant position as above. previously described and a recorder-sender associated with this operator position without cords. In this way, the incoming junction is associated by a coupling with a recorder-sender which was operated either by the remote operator as would be the case when the recorder-sender 2214 is directly associated with the junction, or by the operator without cords as previously described.

   This recorder-sender operates a connection circuit such as that shown in Figs. 73 to 74 to associate a free marker with it and to activate a 4801 route relay by the settings of the recorder relays - As soon as the marker equipment has been activated, a signal is transmitted for

  <Desc / Clms Page number 168>

 indicate the number of the rack on which the cross-bar switch establishing the connection with the calling incoming junction is located. It can be assumed for this example that this calling incoming trunk is connected to the crossbar switch 904 and that the multi-frequency signal is therefore transmitted through the coil of the primary selector electromagnet 902.



   In the marker, the inbound frame number 3501 contact relay is actuated to establish a circuit through which the multi-frequency signal can be transmitted. A circuit can be followed for this relay comprising: earth, contact 4 of relay 6807, conductor 6820, a chain of contacts which are the highest contacts of relays 3701, 3702, 3703 and 3704, and lowest contacts of relays 2729, 2730, 2731 and 2732, conductor 2740, contact 3 of relay 3504, coil of relay 3501 and battery. Relay 3501 is blocked by its contact 2 and contact 4 of relay 3504 by conductor 3545 which joins conductor 6820 extending to earth on contact 4 of relay 6807.

   Relay 3501, in operation, connects the multi-frequency signaling circuit of the incoming primary selector electromagnet coil 902 to the marker circuit. This circuit includes: generators 2072, 2074 and 2078, their respective amplifying circuits and resistors 2013, 2022 and 2035, which are joined to each other and extending through conductor 938 to the winding of individual frame transformer 937. The combination of multiple frequency signals is thus transmitted to the secondary 936 of the frame transformer and through the coil of the selector electromagnet 902, the conductor.

  <Desc / Clms Page number 169>

 tor 927,

   the circuit from the incoming junction calling to the sending recorder or to the cordless position depending on which device has been associated with the incoming junction calling. This signaling circuit extends to the contacts of the crossbar switches of the coupling either in Fig. 22 or in FIG.

     32.If we assume that the circuit passes through the cordless position, the signal conductor extends to conductor 5501 through contact 7 of relay 5505, contact 3 of recorder-sender relay 5601 , conductor 7311, contact 2 of multi-contact connector relay 7304, contact 1 of multi-contact relay 7504, conductor 7471, contact 1 of relay 1707, contact 3 of relay 1714, conductor 1740 , relay 7003 contact 3, conductor 7040, relay 3504 contact 1, relay 3501 normal contact 1, conductor 3540, an input transformer 2702 of the multi-frequency signaling circuit.

   The above circuit followed through the recorder-sender associated with the cordless position is practically the same as the circuit followed through an inbound recorder-sender such as 2214, not associated with the cordless position. and, for this reason, the description of the circuit extending through the recorder-sender may be omitted in this description. The three transmitted frequencies pass through transformer 2702 and associated amplifiers, as well as through filters 2741, 2743 and 2748 to their respective amplifier circuits to actuate relays 2717, 2725 and the relay associated with filter 2743.



  The three actuated relays associate the earth with the conductors 2758, 2756 and 2751 to energize the relays 3701, 3703 and 2732. By operating these last three

  <Desc / Clms Page number 170>

 relays establish a circuit through their contacts to energize the rack relay corresponding to the transmitted signals, which also corresponds to the rack number to which the calling incoming junction is connected. This frame relay is actuated and locked in position in the same manner as described to operate frame relay 3902 which was actuated to indicate the incoming frame number of the interurban train with which the incoming junction is calling. was connected.

   A circuit is also established through the contacts of these relays to indicate whether the frame on which the calling incoming junction is located is an even or odd frame in the same manner as previously described. The inbound rack relay blocking circuit is established in the same manner as described for inbound rack relay 3902 and establishes a switching circuit for the multi-frequency system to restore the normal state of the devices. relay of Figs. 27 and 37 before the transmission of a subsequent signal. The summary of these maneuvers is as follows: relay 3503 is first actuated from the battery by its winding, a circuit extending through the frame relay and contact 5 of relay 6807 to earth.

   Relay 3503 connects the earth of contact 1 of relay 6807 by winding the frame relay and winding a coil such as 2907 to the battery. The traced circuit blocks the rack relay and also establishes an obvious circuit for the 3504 relay. While operating, the 3503 relay also establishes a blocking circuit for itself, which includes: the battery, its winding, relay contact 1 6807 and earth. When operating, relay 3504 triggers the incoming contactor relay 3501 which disconnects the signaling circuit at fre-

  <Desc / Clms Page number 171>

 Multiple frequencies of conductor 3540 extending to transformer 3702. Thus, all the devices of Figs.



  27 and 37 operated to establish the number of the terminating arrival frame are released.



   Output frame number signal.



   As previously described, a free outgoing trunk associated with a switch in the switch termination train was selected by the operation of the 4801 route relay. A circuit route for the operation of the multi-frequency signaling equipment in order to indicate the frame number on which the output junction is located, the triggering of relays 3701, 3703 and 2732, the operation of relay 3504 and the triggering of relay 3501 are prepared.



  A circuit is now established for the outgoing junction frame contact relay 3502 as previously followed from the battery, by its winding, relay contact 3605, relay contact 3508, relay contact 3501, normal. , the contact of relay 3504, the lowest contacts of the signaling relays (Fig. 27), the highest contacts of the signaling relays (Fig. 37), the conductor 6820 and the contact 4 of the relay 6807 to earth . Relay 3502 is blocked by its contact 2 and contact 4 of relay 3508, conductor 3545, conductor 6820 to earth on contact 4 of relay 6807.

   The signals used to activate the outgoing junction frame relay in the marker are transmitted in this case from the generators 2073, 2074 and 2075 by their respective amplification circuits, the resistors 2017, 2023 and 2057 and the conductor 1038 to the signaling transformer of frame number 1035. This transformer is associated with the frame on which the selected outgoing junction is located

  <Desc / Clms Page number 172>

 and is the same as the transformers on the output frames in the switch termination train. The multi-frequency signals reach the primary winding 1037 of this transformer, are passed to the secondary winding 1036 of this transformer, and then travel through the selector electromagnet of the switch to which the outgoing junction is connected.



  For this example, it will be assumed that the multi-frequency signals are transmitted through the winding of the selector solenoid 1010 and conductor 1056 to the associated trunk group relay apparatus in the trunk group relays. connector associated with the allocation connector 5110. This conductor extends through the contacts of the terminal block relay and the multi-frequency connector relay to contact 1 of relays 3810 to 3183 activated for indicate the free junction.

   From contact 1 of the actuated relay, the circuit extends by a chain circuit passing through the contacts of these relays to the conductor 3842 extending to contact 4 of relay 1707, through contact 2 of relay 1714, the conductor 1752, relay contact 1 7003, conductor 7047, relay contact 2904, conductor 2911, conductor 2812, relay contact 7 2801, conductor 2813, relay contact 1 3502, conductor 3513, contact 4 of relay 3507, conductor 3514, contact 2 of relay 3504, conductor 3540 to transformer 2702.

   The three frequencies transmitted on this circuit to control the rack signaling equipment pass through the filters 2742, 2743 and 2744 and their respective amplifier circuits to actuate the associated relays, such as the relay 2717. This associates the earth. to conductors 2757, 2756 and 2755 to actuate relays 3702,3703 and 3704. This establishes a through circuit

  <Desc / Clms Page number 173>

 by the contacts of the latter relays to actuate a frame relay (not shown) which corresponds to the frame number on which the chosen free outgoing junction is located. It can be assumed that this frame relay is actuated in the same manner as the relay 3901 previously described.

   In operation, the aforementioned relays 3702, 3703 and 3704 also establish a circuit through their contacts to indicate whether the frame is odd or even. We can assume that this circuit is one of the combinations previously described. The rack relay is blocked as previously described for rack relay 3901 and thereby opens the multi-frequency signaling circuit extending to transformer 2702 to release the multi-frequency signaling equipment (Figs. 27 and 37). ) which now returns to idle.

   In response to the operation of the apparatus in the marker, indicating the pati numbers in which the terminating train switches of the calling incoming junction and the free outgoing junction are located, and also in response to the operation of the equipment indicating whether these frames are even or odd, circuits are established in the marker to associate the marker with the control relays of the apple connector shown schematically in FIG. 9 and the connector control relays, as shown schematically in FIG. 10. These connector control / relays are associated with each pair of frames in the same way as shown for the connector control relays (Figs. 15, 25 and 26).

   The secondary incoming switches and the primary output switches (Figs. 9 and 10) are therefore chosen to establish a route per conductor of junctions through conductors such as 928, 929,930, 1028, 1029, and 1030, to connect the bar switch

  <Desc / Clms Page number 174>

 primary crossover on the incoming frame to the secondary crossbar switch on the output frame associated with the calling incoming junction and the free outgoing junction chosen as described below.



   Operation of crossbar switches -
Intercity train.
 EMI174.1
 



  --------------------------------------------------
As previously established, a free outgoing trunk to a particular destination was chosen and multi-frequency signals were transmitted to the marker to control the apparatus providing numbers of the frames on which the calling incoming trunk and outgoing trunk are located. free if and indicating these frames are odd or even. For example, the incoming junction may be located on an odd frame of a particular number and the outgoing junction may be located on an even frame of a particular number. The frame numbers indicating the location of the calling incoming trunk switch and the free outgoing trunk switch can both be odd or even or a combination of both.

   The operation of the following apparatus will be reviewed and will occur under the action of the multiple frequency frame number signaling apparatus to facilitate circuiting by the contacts of this apparatus so that the - clearly appears the operation of the coupling and connector circuits serving to connect the marker to the incoming and outgoing switches which must be actuated to establish communication. ..The example chosen for the connection to be described is the case in which the incoming junction is located on an even frame 0 and the outgoing junction is located on an odd frame 39.

   Relay 3902 was actuated to signal to the marker that the frame on which the ring is located

  <Desc / Clms Page number 175>

 Incoming calling tion is frame 0. This relay is actuated by a circuit comprising: the battery, the coil of relay 2907, resistor 2910, coil of relay 3902, conductor 3962, contact
5 of relay 3501, the relays of Figs. 27 and 37 and earth. When the incoming junction is located on an odd frame, the frame number signaling device actuates relay 2901 from the battery by winding up this relay, conductor 2940 and contact 4 of relay 3501 until earth by a combination of relays in Figs. 27 and 37.

   When the incoming junction is located on an even frame, relay 2902 is actuated from the battery by its winding, conductor 2941, contact 3 of relay 3501 to earth by a combination of relays in Figs. 27 and 37. The output frame relay 3901 is operated from the battery by the windings of relay 2908, resistor 2909, the winding of relay 3901, conductor 3963, contact 6 of relay 3502, and contacts of a combination of relays at Fip; s. 27 and 17 down to earth.

   When the outgoing junction is located on an odd frame, the relays 3903 and 3905 are actuated from the battery by the windings of the two relays, the conductor 3960, the contact 4 of the relay 3502, the relays and a combination of relays in Figs. 27 and 37 which are set by the number indication device down to earth on contact 5 of relay 6807. When the chosen free outgoing junction is located on an even frame, relays 3904 and 3906 are actuated from the battery by their windings, the conductor 3961, the contact 3 of the relay 3502 and a combination of relays in Figs. 27 and 37 to earth on contact 5 of relay 6807.



   The cross-bar switch racks to which the coupling and connector circuits and equipment

  <Desc / Clms Page number 176>

 output shown to Fi; s. 15, 25 and 26 are associated, are provided in pairs with a connector, as shown in Figs. 15, 25 and 26 in pairs of frames. Each connector is arranged to associate conductors of junction conductors sockets, conductors of coupling sockets as well as the windings of the primary selector electromagnets with various conductors of various kinds coming from any of the primary or secondary switches located. on one or the other of the frames forming a pair, these circuits being established through the marker by the apparatus which indicates the situation of the incoming and outgoing junctions on the frames of switches.

   This arrangement allows the marker to try out the greatest number of junction conductor socket conductors between the incoming secondary crossbar switches shown in the right side of FIG. 9 and the output primary crossbar switches shown in the left part of FIG. 10, or between the incoming secondary crossbar switches shown in the right part of FIG. 14, and the primary output switches shown in the left partial of FIG. 15. The connector and coupling circuit for a pair of frames as neutralized in Figs. 15, 25 and 26 has four distinct tracks, two extending from FIG. 25 to the even and odd frames of the pair and two extending from FIG. 26 to even and odd frames of the pair *.

   Fig. 25 shows the connector and coupling for the odd rack. The two paths traversing this connector and coupling circuit will be identified here as the local and corresponding paths. The local route of FIG. 25 connects the marker to the switches of the odd frame, the corresponding channel connects the marker to the switches of the even frame. In the coupling and connector circuit

  <Desc / Clms Page number 177>

 shown in FIG. 26, 1A local channel connects the marker to the switches on the even rack and the corresponding channel connects the marker to the switches on the odd rack.



   For example, if a free outgoing trunk which has been chosen for telephone communication is located on an odd rack, and if the uneven couplings and connectors, in Fig. 25, were chosen by the marker, the local path is employed between the marker and the crossbar switches in the upper part of FIG. 15. If this free outgoing junction is located on an odd rack, and the marker has chosen an even coupling and connector circuit such as that shown in Fig. 26, the corresponding channel is used to connect the marker to the crossbar switches on the odd frame where the crossbar switch connected to the junction is located.



   The operation of the marker, when it is associated with a particular coupling and connector as shown in FIG. 25 or in Fig. 26, is initially directed by the recorder-sender which is actuated to establish the link. If the recorder-sender has an odd number, the marker is directed to an odd coupling and connector circuit, as shown in Fig. 25. This maneuver is considered the first attempt which, if successfully established, establishes the connection appropriately. If, on the first attempt to establish the link, the marker is picked up by an even numbered register-sender, then the marker prefers an even-numbered coupling and connector circuit as shown in FIG. 26.

   In each case, the local channel or the corresponding channel is used depending on the situation of the crossbar switch connected to the selected free outgoing junction. When a second attempt is required due to a marker failure, the recorder-

  <Desc / Clms Page number 178>

 associated sender is set by this tag before its release so that a different circuit is established in another tag which is seized by this recorder-sender to establish the link. This new setting is such that, when an odd coupling and connector circuit, Fig. 25 is entered during the first test, the coupling circuit and the even connector, FIG. 26, is seized during the second attempt. When the local channel of a circuit (the coupling and connector is entered on the first try, the corresponding channel is entered on the second try.

   As a consequence of this, when an odd coupling and connector circuit is grasped on the first try, and the local path is grasped, the connection is made from the marker to a crossbar switch by that local path, and on a second try, the other frame and connector or even frame and connector is grasped, and the connection is made from the marker through the corresponding channel thus reaching the crossbar switches on the same frame as through the local channel during from the first try.

   This applies to both interurban train arrival and termination crossbar switch racks, as well as interurban train exit and switch termination crossbar switch racks. times as well as the associated coupling and switch circuits. The input of coupling and connector circuits associated with particular cross-bar switch racks is regulated as established here by the recorder-sender and also by the multi-frequency signaling circuits which establish the connections which must exist between the marker and the special frames.

  <Desc / Clms Page number 179>

 



   Assume that the marker circuit was picked up by an odd-numbered register-sender on the first attempt to establish the connection as described.



  In this case the marker will prefer odd-numbered coupling and switch circuits to associate the marker with switches associated with the calling incoming junction and those associated with the free outgoing junction. The coupling circuit and the connector associated with the outgoing junction switches are first activated by the marker which connects the battery through the start lead 2533 to actuate the associated marker preference relay 2522. Assume that relay 5101 was actuated by an odd-numbered recorder-sender making a first try and relay 3905 was actuated by the rack number signaling equipment since the incoming junction is on an odd rack.

   The circuit for the starting conductor can therefore be followed from the battery by resistor 1908, contact 6 of relay 1903, contact 1 of relay 2906, con-
1 tact / of relay 2905, conductor 5133, contact 1 of relay 5101, contact 1 of relay 3901, conductor 2533 and marker frequency relay winding 2522 to ground. This ground is associated with one of the relays in a chain of relays which are used to prevent more than one marker from being connected to the same connector circuit.

   These relays as noted, have wiring established on a preference and blocking basis, and as indicated by the wiring, the marker preference relay 2522 has a first preference for actuating its marker preference relay 2522 but a last preference to actuate its associated connector relay 2513, which is why when one of the other marker preference relays in the relay chain is actuated, the marker must wait for its release.

  <Desc / Clms Page number 180>

 tion before actuating the associated multiple contact relay 2513 in the connector. When operating, relay 2522 associates the earth through its contact 4 with the winding of relay 2513 which is operating.

   If it is assumed that the local channel is the one that must be used, a circuit is established by contact 2 of relay 2522 to activate the relay of local channel 2502. If, on the contrary, it is the corresponding channel that must be used, a circuit is established through contact 1 of relay 2522 which operates local channel 2503.



   The above circuits are established by the operation of the apparatus. The marker responding to the transmitted multi-frequency signals gives the species of the frame, even or odd, on which the junction is located as previously described. Local channel relay 2502 is actuated by conductor 2531 extending from marker through contact 2 of relay 2522, or local channel relay is actuated by conductor 2532 extending from marker through contact 1 relay 2522 following the multi-frequency signal transmitted to the marker.

   The operating circuit of relay 2502 includes: earth, contact 1 of relay 2503, winding of relay 2502, contact 2 of relay 2522, conductor 2531 which is connected to conductor 3931, contact 4 of relay 3905 which is actuated, contact 5 of relay 3906 which is normal, conductor 1920, contact 5 of relay 1903, resistor 1909 and the battery.

   If use is made of the corresponding channel and if a circuit is established by the conductor 2532, to extend the connection to a corresponding frame, which in this case would be an even frame, the relay 2503 is actuated by a circuit comprising : earth, contact 6 of relay 2502, the coil of relay 2503, contact 1 of relay 2502,

  <Desc / Clms Page number 181>

 the winding of relay 2503, contact 1 of relay 2522, conductor 2532 which is connected to conductor 3932 by contact 5 of relay 3905 normal, contact 4 of relay 3906 activated, conductor 1920, contact 5 of relay 1903 , the resistance 1909 and the battery. In case the marker has been connected to an even connector (Fig.

   26), and where the marker preference relay 2622 was actuated, the aforementioned conductors 3931 and 3932 from the circuit followed to the battery by the marker apparatus, are reversed with respect to the local and corresponding channels, that is i.e., conductor 3931 is connected to conductor 2631 to actuate the corresponding track switchgear to extend the odd frame marker conductors, or conductor 3932 is connected to conductor 2632 to operate the switchgear. of the local track on the even frame. This arrangement is shown in the drawing.

   In the circuits followed to actuate either relay 2502 or relay 2503, it will be noted that the earth for the operating circuit of relay 2502 of the local channel is taken by the contact of the relay of the corresponding channel 2503 and that the earth for the relay of the corresponding channel is taken by a contact of the relay of the local channel.



  Therefore, when either of these relays is operating, the circuit of the other relay is open so that the other channel cannot be mistakenly used by another marker.



   Below are the combinations of devices that can be operated in the marker in response to different situations, combinations that will be useful to enter, if one wishes to understand the operation of the devices in response to the association of the marker with the coupling and connector circuit.

   When an outgoing junction on an even incoming frame is to be connected

  <Desc / Clms Page number 182>

 Tied at an outgoing junction on an even output rack, relays 3904, 3902 and 2902 are actuated by the multi-frequency rack number signaling device. Cepi establishes for relay 3907 a circuit comprising: the battery, its winding, contact 1 of relay 3904, contact 4 of relay 3902, contact 2 of relay 2902, contact 3 of relay 3904 and earth.



  If an incoming junction on an odd incoming frame is to be connected to an outgoing junction on an even outgoing frame, relays 3904, 3902 and 2901 are actuated by the frame number signaling device and it is established. for relay 3908 a circuit comprising: the battery, its winding, contact 2 of relay 3904, contact 5 of relay 3902, contact 6 of relay 2901, contact 3 of relay 3904 and earth.

   If an incoming junction on an odd-numbered incoming frame is to be connected to an outgoing junction on an odd-numbered output frame, relays 3903, 3902 and 2901 are actuated by the frame number signaling device which establishes for the relay 3909 a circuit comprising: the battery, its winding, contact 1 of relay 3903, contact 4 of relay 3902, contact 2 of relay 2901, contact '3 of relay 3903 and earth.

   If an incoming junction on an even incoming frame is to be connected to an outgoing junction on an odd outgoing frame, relays 3903, 3902 and 2902 are actuated by the frame number signaling device which establishes for the relay 3910 a circuit comprising: the battery, its winding, contact 2 of relay 3903, contact 5 of relay 3902, contact 7 of relay 2902, contact 3 of relay 3903 and earth.



   Assuming relay 2502 is actuated by a start circuit from the marker,

  <Desc / Clms Page number 183>

 circuits are established by its contacts to operate the equipment associated with the local channel.



   Relay 2501 is actuated from earth by its winding, contact 1 of relay 2502, resistor 2505 and the battery. Further circuits are established by the contacts of relays 2513, 2502 and 2531 to operate the test relays and establish circuits to the marker, as well as to find a free junction conductor path between the switches of the marker. incoming secondary and primary output switches, whereby the connection can be made from the incoming junction on the primary incoming switches to the outgoing junction on the secondary output switches. In operation, relay 2513 associates earth with conductor 2534 which extends through the winding of relay 1802 to the battery.

   This relay operates after relay 2513 in order to verify the operation of relay 2513 and to establish circuits in the marker at the appropriate time. A verification circuit is also established to the marker from the battery by contact 8 of relay 2501, contact 5 of relay 2513, conductor 2539, relay winding.
1805, to return via conductor 2540, contact 6 of relay 2513, contact 4 of relay 2504 to earth, making relay 1805 operate.



   Inbound junction rack coupling and connector.



   -------------------------------------------------- -
A circuit is now established to initiate the operation of the coupling and connector circuit 1420 associated with the arrival frame. This coupling and connector circuit is shown schematically at 1420 and is substantially the same as that shown in Figs. 15, 25 and 26 and it can be assumed that its operation is practically the same. The start-up circuit

  <Desc / Clms Page number 184>

 The following che is established by the marker relay contacts which were actuated by the multi-frequency frame number signaling apparatus as previously described, to indicate the frame on which the incoming junction is located.

   This starting circuit includes: the battery, resistor 2506, contact 2 of relay 2502, contact 8 of re-. but 2513, conductor 2541, contact 1 of relay 1903 which is actuated, contact 2 of relay 5101 which is actuated to indicate that the call is from an odd recorder-sender, contact 1 of the frame relay Incoming 3902, also actuated and earthed by a marker preference relay in the incoming coupling and connector circuit 1420 which is the same as the marker preference relay 2532, shown in Fig. . 25 for the output frame.

   This incoming coupling and connector circuit now operates to test and establish operating circuits at the same time as the output coupling and connector circuit, as will be described for the output circuit and assigned. the maneuvers of the arrival frame when they occur. In response to the operation of the relay preferably in connector 1420, relays operate which are the same as the relays actuated in the output connector, such as 2513, 2502 and 2501.



   In operation, the foregoing relays 3907, 3908, 3909, and 3910 establish circuits for any one of a number of these, such as 1520 to 1523, in the local channel, or similar relays, such as 1532 to 1535 in the corresponding channel. For this example, assume that relay 3909 has been actuated to establish a circuit through junction conductor breaker relay 1523, which includes:

  <Desc / Clms Page number 185>

 earth, its winding, contact 3 of relay 2513, conductor 2536, contact 1 of relay 3909 activated, contact 2 of normal relay 3910, conductor 2542, contact 9 of relay 2513, contact 3 of relay 2502, resistor 2507 and the battery.

   Relay 1520 is actuated in a similar circuit, except that the circuit is established by contact 1 of relay 3910 when actuated and returns by conductor 2942 in the same manner as followed for relay 1523. . a circuit is also established for actuating the selector electromagnet of the outgoing junction switch 1510 from the battery through resistor 2509, contact 5 of relay 2502, contact 10 of relay 2513, conductor 2543, contact 1 of relay 3905, conductor 3943, contact of relay 2904 which is actuated, contact 1 of relay 7003, contact 2 of relay 1714, contact 4 of relay 1707, conductor 3842,

     contact 2 of relay 3310 which was actuated when the free junction was found, conductor 3841, specific to the free junction chosen by contact 9 of relay 4122, contact 2 of relay 3116, the winding of the electro- mant secondary selector 1510, winding 1518 of the frame number 1517 signaling circuit tramter to ground. The preceding circuit is followed to actuate a secondary selector electromagnet, when the selector electromagnet is associated with a junction on an odd frame.

   A similar route can be followed from the battery by contact 2 of the corresponding relay 2503, conductor 2544, conract 1 of relay 3906 to actuate a secondary selector electromagnet on an even frame, as indicated by the signaling equipment of the frame number.



   An obvious circuit is established for relay 1526

  <Desc / Clms Page number 186>

 comprising: the battery, resistor 2508, contact 4 of relay 2502, the winding of relay 1526 and earth. The operation of relay 1526 and the previous operation of the secondary selector electromagnet of the outgoing junction establish a circuit to actuate the coupling contactor relay 1521 from the battery through resistor 1527, contact 1 of relay 1526, the relay winding 1521, contact 3 of relay 1526, the contact of a selector electromagnet such as 1510, associated with the selected free outgoing junction and earth.

   A circuit is established to actuate three relays in the marker from earth on contact 1 of relay 2521 or contact 1 of relay 2524, contact 1 of relay 2501, contact 1 of relay 2514, conductor 2545 by the winding of relay 4012 up to the battery in multiple with the right winding of relay 4044 up to the battery.

   Conductor 2645 also extends through contact 4 of relay 4906 to the battery through the winding of relay 4911. Another circuit is established from earth through contact 1 of one of relays 1520 to 1523 inclusive, which may include ten relays, then through contact 2 of relay 2501, contact 2 of relay 2514, conductor 2546 to the battery through the winding of relay 4011.



   Channel selection.



   -----------------
There are several channels between each primary output crossbar switch and each secondary incoming crossbar switch to connect the primary incoming crossbar switch to the secondary output crossbar switch. The output connector circuits (Figs. 15 and 25) have been actuated as previously described to associate conductors coming from all of said tracks shown in Fig. 30 of the marker. The track circuits in Fig. 30 are thus connected to all the available tracks between

  <Desc / Clms Page number 187>

 the primary output switches and the secondary incoming switches which can be used to establish this link, whether these channels are free or busy.

   The occupied channels actuate the switchgear of FIG. As will therefore be described by way of removal and sequence circuitry, a free path is chosen. Three routes have been shown in FIG. 30 as an example of a plurality of routes employed. In order to determine which lanes are occupied when the marker is associated with these lanes, the windings of the relays 3004, 3006 and 3008 are connected by the output connector circuit to the switches of the coupling. The circuit for relay 3004 includes: the battery, extending through the coil of relay 910 to contact 1 of relay 4906, conductor 3026, coil of relay 3004, contact 5 of relay 3001, conductor 2549 and the connector circuit.

   This conductor extends through contact 5 of relay 2514, contact 7 of relay 2501, contact of jack 1528, and contact 2 of relay 1524 to socket conductor 1570. A similar circuit extends through contact 2 of relay 1521 to another socket circuit. In this way all switch socket circuits are tested. The straight windings of relay 3005 and other similar track relays 3007 and 3009 test the holding electromagnet. This circuit includes: the battery, relay winding 4960, contact 2 of relay 4906, lead 3025, right winding of relay 3005, contact 4 of relay 3001, lead 2548, and output connector. This conductor extends through contact 4 of relay 2514, contact 6 of relay 2501, contact 2 of relay 1520, to the winding of the holding electromagnet 1507.

   A circuit is also extended to the incoming conductor by the left winding

  <Desc / Clms Page number 188>

 relay 3005, which comprises: the same battery source, the left winding of relay 3005, contact 2 of relay 3001, conductor 1950, a series of contacts in connector circuit 1420 and the electromagnet of primary maintenance of arrival 1412.



  When a junction conductor coupling between a primary output switch and a secondary incoming switch has been grasped by another marker to make a telephone link or a link by means of which telephone communication is made, earth is associated with the holding electromagnet to keep these crossbar switches in action. For this reason, if the earth is associated with a bushing conductor or with the holding electromagnets of a track, either from the output end or from the input end, the track relays of Fig. . 30, 3004, 3006, 3008 or 3005,3007, 3009 associated with these lanes are actuated to 'indicate that the lane is occupied.

   If a lane is found free, the marker then prepares to enter this lane as follows:
The previously described operation of relays 4012 and 4011, which responded to the operations of the coupling circuit breaker relay 1521 and the junction conductor contactor relay 1523 on the output frame, established a circuit to operate the relays 4010 and 4004. whether the input connector circuit relays similar to relay 1521 on the output frame have also operated. The 4010 relay circuit consists of: the battery, its winding, contact 2 of relay 4011, contact of relay 4012 and conductor 1925.

   The circuit of relay 4004 is also followed by its left winding to conductor 1925 which extends to input connector circuit 1420. This circuit continues in the input connector by a

  <Desc / Clms Page number 189>

 conductor similar to conductor 2545 in the output connector which extends through a contact of a relay similar to relay 2514, the contact of a relay similar to 2501, to earth on the relay similar to 1524.



  When actuated, relay 4010 blocks at conductor 1925 through the contact of relay 4012. This blocking circuit extends around the contact of relay 4011, so it will not trip if relay 4011 goes. triggered during a new test of the connecting conductor.



  Note that a relay contact 4010 which is in parallel with the rear contact of relay 4011, removes an earth which has kept relay 4009 unactuated and allows current to flow through the unactuated winding of relay 4005 to charge the capacitor. 4016. After a period of time measured by the charge capacitor 4016, the current in the unactivated winding of relay 4009 decreases and the primary operating winding takes control and operates relay 4009. In this way, a period of time is allocated for the operation of the slowest track relay 3004, 3005, 3006, 3007,

   3008 or 3009 if the junction conductor connection was entered by another marker between the time the channel was found occupied and the time it was entered. If a free channel is available, testing and operation of relay 4009 causes a channel relay in the marker circuit such as relays 3001, 3002, and 3003 to operate.

   If it is assumed that the first channel is free, for the channel relay 3001, a circuit is established comprising: earth, contact 4 of relay 1801, conductor 1810, contact of relay 4009, contact 2 of relay 4002 , contact 7 of relay 4001, conductor 4040, front contact 2 of relay 1806, front contact 2 of relay

  <Desc / Clms Page number 190>

 
1805, conductor 1840, contact 2 of relay 5806, conductor 5921, contacts of the first normal pair of relays 3005 and 3004, the coil of the relay of the associated channel 3001, contact 1 of relay 4003 and the battery .

   The track relay 3001 is blocked by its contact 3 in a chain circuit passing through the contacts 3 of the relays 3002 and 3003, by the driver
1810 and contact 4 of relay 1801, to earth.



   It is clear that when operating any of the relays 3004 to 3009 inclusive, when connected to busy circuits as described, will open the circuit extending through their contacts to the windings of the track relays 3001 to 3003. , inclusive.



   In certain cases, a holding electromagnet may appear free during the test, but may have just been released by another connection and not have had time to return to rest - In order to ensure that the holding electromagnet d ' a switch is seized by a connection, before they have had time to return to idle, use is made of a counting arrangement. the duration to ensure the recovery of the finger, selector on the crossbar switch before it is entered again.

   If a crossbar switch were to be gripped, before the trigger finger has had time to return to rest, successive operations may be performed incorrectly and result in failure of the proper slow setting of the switch. telephone communication In order to prevent an error of this kind, a counting has been provided for the duration of the maintenance electromagnet, by making the relay 4001 to earth work on the relay 1803 by the rear contact of the relay 4008 and to earth on relay 4002. Relay 4002

  <Desc / Clms Page number 191>

 operates to earth on relay 1801; for this reason, this circuit can be closed first.

   Relay 4002 also associates earth with the top winding of its operation of relay 4008 and bypasses capacitor 4019. If relay 4008 is not on its rear contact at the start of the connection, relay 4002 causes it to trip. Selecting a channel by the operation of a channel relay such as 3001 causes relay 4002 to trip, removing ground from an unactivated winding of relay 4008 and allowing capacitor 4019 to charge in series with that winding.

   After an up time period measured by the charge time of capacitor 4029, the lower winding of relay 4008 takes control and operates the relay, causing relay 4001 to trip and controlling the incoming coupling and the output coupling to the windings. primary of relays 1701 and 1702 respectively. The lapse of time measured by the operating time of relay 4008 and the tripping time of relay 4001 is sufficient to allow a previously actuated holding electromagnet to return to rest and to present an unlocked selector finger.



   In order to allow the establishment of circuits for the aforementioned relays 1701 and 1702 in order to finally actuate the primary input and secondary output holding electromagnets, a circuit must first be made passing through the conductor. socket of the particular outgoing junction which extends to contact 1 of relay 3810. In addition to operating relays which are necessary to guide the actuated holding electromagnet, this circuit also tries, when established. , the continuity of the socket conductor of the particular joint. This continuity test is performed

  <Desc / Clms Page number 192>

 by relays 1706 when relay 3810 is operating. A potential is applied to the socket of the outgoing junction to reveal the occupied junction as soon as it is grasped.

   This potential operates a relay in the outgoing junction associated with the socket conductor and may be followed from the battery by relay 1610 in the circuit of the chosen outgoing junction, the allocation connector apparatus of FIG. 41, conductor 3125, contact 1 of relay 3810 which is actuated, conductor 3840, contact 7 of relay 6101, conductor
6140, contact 5 of relay 1714, the relay winding
1705, the winding of relay 1704, a potentiometer including the battery on conductor 1743, from contact 6 of relay 4001 and resistor 4015, and earth through resistors 1717 and 1716, then the conductor
1760, contact 1 of relay 1740, conductor 1723, contact 3 of relay 5105 or 5106, contact 3 of relay
1902 and the earth.

   Relay 1704 operates in the circuit followed above and establishes a circuit to operate relay 1706 which locks at contact 3 of relay 1802 and establishes a ground circuit to the operating windings of polarized relays 1701,
1702 and 1709 which now makes them effective for testing coupling and connecting conductor. This, however, does not constitute an operating circuit for the above relays 1701, 1702 and 1709. This operating circuit will be described later.

   Relay 1706 reduces the potential applied to the socket to a value somewhat closer to that of the earth to ensure the operation of the socket relay of the outgoing junction 1610 in the event that it has not previously operated with the higher potential which was required to operate relay 1704.

  <Desc / Clms Page number 193>

 



   After relay 1706 has operated and a clear path has been selected through the jumper conductors from the secondary incoming switches to the primary outgoing switches, the holding electromagnets operate and the double connection test takes place. On tripping, relay 4001 initiates testing and operation of the holding electromagnets by connecting the primary windings which are the top windings of relays 1701 and 1702 to the holding electromagnets of the primary incoming and secondary output couplings, respectively. . These windings on which the earth is found as previously followed from contact 3 of relay 1901 to contact 1 of relay 1706 have a comparatively high resistance and cannot operate the holding electromagnets.

   Their role is to test the continuity of the conductors to the holding electromagnets, working if they find a battery on these conductors, which is the normal state. This circuit includes: the battery, the windings of the holding electromagnets, the conductor 1570, the contact 2 of the relay 1524, the contacts of the jack 1528, the contact 7 of the relay 2501, the contact 5 of the relay 2514, the conductor 2549 , contact 5 of track relay 3001, which has been activated, conductor 3409, contact 1 of relay 4001, contact 7 of relay 1714, the top primary winding of relay 1702, conductor 1649, the contact 2 of relay 1904, conductor 1949, the top primary winding of relay 1701, conductors 1750,

   contact 6 of relay 1714, contact 3 of relay 4001, conductor 3050, contact 2 of track relay 3001, conductor 1950, coupling and incoming connector 1420, conductors 1470 and the electromagnet 1412. The relays 1701 and 1702 operate and are blocked on their lowest tertiary windings by the continuity contact 2 of the
1

  <Desc / Clms Page number 194>

 relay 1703. At the same time as the winding of the relay
1703 is easily earthed by the contacts of relays 1701 and 1702 in series, this same earth is connected to the holding electromagnets of the secondary input and primary output switch 1422 and 1507 which also operate.

   This circuit includes: the battery, the two windings of the holding electromagnets 1422 and 1507, the contact 2 of the relay 1520, the contact 6 of the relay 2501, the contact 4 of the relay 2514, the conductor 2548, the contact 4 of the channel relay 3001, conductor 3020, contact 2 of relay 4001, contacts of relays 1702 and 1701 which are actuated as established, contact 1 of relay 1714, conductor 1723, contacts 3 of relay 5106, contact 3 of relay 5105 , conductor 5123, contact 3 of relay 1902 and earth.



   In operation, relay 1703 bypasses the high resistance upper primary winding of relay 1701 and relay 1702 and now establishes a low resistance circuit to actuate the incoming primary and output secondary holding electromagnets. Relay 1703 also removes earth from the tertiary circuits of relays 1701 and 1703 to reduce the negative potential on the socket circuit and to aid in the operation and maintenance of the holding electromagnets and socket relays of the incoming junction and of the output junction. The earth that has been applied to these various socket conductors from contact 1 of relay 1714 shunts the operating winding of dual connection test relay 1709.

   When all of the hold electromagnets have operated and both tip and neck conductor sets have been closed, relay 1712 operates, which now operates relay 1714. When operating, relay 1714 removes the relay. shunt relay 1709 and remove solid earth from the

  <Desc / Clms Page number 195>

 junction conductor socket. Relay 1709 is now connected to the junction conductor socket in series with the holding electromagnets. If there is no double connection as indicated by the absence of earth on the junction conductor socket, the relay
1709 works in series with the holding electromagnets and at the same time keeps the holding electromagnets activated.

   If there is a double connection, the earth will be on the socket conductor and will not allow the operation of relay 1709 which blocks the next degree of progress of the marker operation and ultimately causes the marker to disconnect afterwards. a certain amount of time. While operating, relays 1709 and 1714 cause relay 1715 to operate which locks up and removes ground from conductor 7312 to the marker connector. This lead extends through the marker connector to the 6601 recorder-sender relay that operated through this circuit. When earth is removed, relay 6601 trips, which applies a holding earth to the holding electromagnets through their contacts and through the incoming junction circuit.

   The circuit for this grounding comprises: the holding solenoid 1411, the socket conductor, the switch 1407, the conductor 1456, the conductor 1452, the circuit of the incoming junction, contact 7 of the relay of the junction. input 1213, conductor 3229, primary crossbar coupling switch contact 10 3200, secondary coupling switch 3203 extending through conductor 5551, relay contact 7 5585, conductor 5551, contact 3 of the relay 6601, relay contact 1 6605, relay contact 4 6604, relay contact 3 6609, relay winding 6608 and earth, high resistance contact 5 and the battery.

   This earth is connected to the marker by the conduc-

  <Desc / Clms Page number 196>

 socket tor and bypass the previously actuated relay 1709. At the same time, relay 1711 would have operated in the circuit followed by contact 3 of the relay.
1715, contact 5 of relay 1714, conductor 6140, contact 7 of relay 6101, contact 1 of relay 3810, 1 contact of relay 3814, conductor 3125 as previously followed by the allocation frame and by the conductor 3126 to the outgoing junction socket extending through the crossbar switch cross points of the output frame to ground in the marker through conductor 1570 as previously followed.

   This checks the crossing points of the sockets of the primary output and secondary output cross-bar switches. The relay 1709 being normal and the relays
1715 and 1711 being actuated, the operating path of the 1901 marker release relay is partially established. This test, together with the tip and neck continuity tests to be described, checks each cross point for continuity and checks the coupling and junction conductor sockets for continuity, verifies whether there is no dou - make connections as indicated by the absence of earth on the socket conductor and check the application of earth, hold by the recorder-send circuit or position.

   The tip and neck conductors passing through the switches are checked for continuity by the marker. Coil 1726 and variable resistor 1725 connect the ungrounded battery to conductors 1753 and 1752 in series with the coil of relay 1712. This circuit can be traced as follows: The applied test extends from the coil of relay-1712 through the marker connector relay contacts 7304, leads 7356 and 7357, contacts 1 and 7 of the logger-sender relay 5706 which is normal, leads 5736 and 5757, contacts

  <Desc / Clms Page number 197>

 
3 and 4 respectively of relay 5505, the coupling switches 3203 and 3200, the incoming junction with return to the circuit and the cross points of the connection switches.

   This circuit becomes effective when generator ground is applied to coil 1726 and when all tip and neck cross points are closed.



   Connection of junctions.



   -----------------------
The outgoing junction switchgear, in Fig. 16, is partially activated when the junction is found free after the test of this junction is completed, and the rest of the switchgear is activated when the cross points of the switches in the whole train of switches were closed. Relay 1010 is actuated when the junction is found free. The operating earth for this relay is replaced by a holding earth as soon as the switch points have been closed.

   This holding earth is the same as that placed on the socket conductor by the incoming junction to keep the holding electromagnets actuated and can be followed by contact 4 of relay 1304 in the incoming junction by contact 9 of relay 1301, socket conductor 1452, switch contacts, socket conductor 1561, relay winding 1610 and battery. As previously established, each time the seission relay 1301 is actuated, the earth which has just been followed from the con. tact 4 of relay 1304 is replaced by the. earth coming from the switchgear of the trunk line without leads.

   To follow this circuit, remember that relay 6505 was actuated and locked to earth on contact 7 of relay 6511 when the switchgear in the position was operating; this is why this earth circuit

  <Desc / Clms Page number 198>

 socket can be followed - from earth on contact 8 of relay 6511 by contact 2 of relay 6505, the winding of marginal relay 6506, contact 5 of relay 5604, contact 6 of relay 5609, contact 5 of relay 5601, contact 4 of relay 6603, contact 7 of relay 5507, conductor 5550, contacts of coupling switches 3203 to conductor 3228 to a point of junction with socket conductor 1452.

   The relay 1610 and the holding electromagnets are therefore kept in the actuated state in this case after the outgoing junction has been seized. In operation, relay 1610 disconnects ground from test conductor 3127 and associates this ground with a holding circuit for relay 1615 through its left winding and contact 1, which circuit is effective as soon as this relay is actuated. @e relay 1615 is actuated from the earth by its right winding, contact 1 of relay 1610, contact 4 of relay 1516, resistor 1617 'up to the battery. While operating, relay 1615 establishes an obvious circuit for the call relay 1612 through its contact 3 and establishes a circuit for the time count relay 1613 to ground through its contact 2.

   While operating, relay 1612 applies inrush current through junction 1624 to remote trunk office 162. Relay 1613 requires 2 seconds to operate which allows the remote office to be called for 2 seconds as explained later. During this time, relay 1615 is blocked from the battery by resistor 1614, contact 1, its left winding to earth on contact 3 of relay 1610.

   While operating, the switches of the interurban train establish a circuit through the neck conductor to operate the relay 1616 as follows: the battery by the winding of the relay 1616 is extended by its contact 3, the contact 2 of the relay

  <Desc / Clms Page number 199>

 
1610, the lower winding of the shock coil 1611, the neck conductor, the contacts of the actuated switches, the incoming junction conductor 1451, the shock coil 1324, the contact 7 of the relay 1304 which is actuated , the conductor 3227, the contacts of the coupling switch 3200 and of the coupling switch 3203 which are activated, the conductor 5553, the contact 9 of the relay 5505 which is activated, the contact 5 of the normal relay 56u9, the contact
2 of relay 5606 normal, contact 4 of relay 6601 normal,

   contact 2 of relay 6611 which is activated will actuate the high resistance right-hand winding which relay 5605. Relay 5605 operates by the circuit followed but the relay
1616 in the outgoing junction circuit does not work due to the high resistance of the right winding of relay 5605. While operating, relay 5605 establishes an obvious circuit for relay 5606, which when operating, locks at the earth on contact 8 of relay 2408. When operating relay 5606 associates earth through the low resistance left winding of relay 5605 and the circuit followed to the battery by the winding of relay 1616. Relay 1616 operates. now.

   While operating, relay 1616 opens the circuit followed from the neck conductor by its winding and connects the neck conductor by its contact 3 to earth on the contact of relay 1609, which causes the trip of relay 5605. The Relay 5605 having tripped and relay 5606 being actuated, a circuit is established for relay 5607 comprising: earth, contact of relay 5605, contact 2 of relay 5606, the winding of relay 5607 and the battery. When operating, relay 5607 associates the monitoring lamp in position 5517 with the neck conductor as follows: As previously followed, the circuit on the neck conductor passes through the

  <Desc / Clms Page number 200>

 internal spring of contact 2 on relay 5607.

   In operation, relay 5607 associates this conductor with the associated armature and from there through contact 10 of relay 5505 to a midpoint between the battery and monitoring lamp 5517 to which the other terminal of the filament is connected. to earth on contact 6 of relay 5512. Earth extended from the relay contact of outgoing junction 1609 through the lower winding of the shock coil 1611 and the neck conductor establishes a shunt for the monitoring lamp 1517 which turns off the lamp, indicating to the operator that the equipment at the outgoing junction has operated satisfactorily. Coming back to relay 1616 of the outgoing junction, this relay disconnects while operating the battery, connected to test conductor 3126 by the winding of relay 1610 and connects the earth by its contact 1 to this conductor of. test .

   While operating, relay 1616 also opens the circuit to the battery through resistor 1617, contact 1 of relay 1610 and the right winding of relay 1615 to ground. Relay 1615 is now kept actuated by its left winding hold circuit. The relay 1616 establishes for itself a blocking circuit comprising: the battery, its winding, its contact 2, the contact 3 of the relay 1610 and the earth. The circuit of the call signal passing through its contact 5 is also open.

   After a period of two seconds, relay 1613 operates through the circuit established to earth on contact 3 of relay 1610, and while operating, connects the earth through its contact to the midpoint of the blocking circuit for the relay. 1615, thus bypassing the battery from the left winding of the latter relay and causing it to trip. When triggered, relay 1615 opens the circuit of call relay 1612 which ends the ringing call via junction 1624.

  <Desc / Clms Page number 201>

 to remote office 1620. If the operator at office 1620 wanted to send a signal to the long distance operator without cords, inrush current would be applied to junction 1624 which would operate relay 1609, to disconnect the earth from the conductor of neck.

   This opens the shunt path previously followed towards the midpoint of the circuit for the 5517 lamp thus causing the lamp to be ignited from the battery, by its filament to the earth on contact 6 of relay 5512. The attendant without cords respond to the signal by associating its earpiece equipment with the tip and neck conductors extending through the contact points of the crossbar switches.



   Operation of crossbar switches in the termination train.



   -------------------------------------------------
The connector control circuits 90 and 1000 associated with the crossbar switches of the terminating train of incoming switches and of the output switches of the terminating train, are the same as those which have been shown and described to associate the marker with the. intercity train switches. The operation of the marker and of the connector apparatus is the same as that which has been described for Figs. 15, 25 and 26 and or: Finds it unnecessary to describe it again to illustrate the operation of the crossbar switches of the switch termination train.



   Second attempt to establish the link.



   ------------------------------------
When the marker is disturbed, and therefore unable to establish a link between the calling incoming junction and the desired outgoing junction, the time count circuit is actuated as previously described, which operates the relay relays. the lower part of FIG. 51, causing relay 5103 to operate. This relay connects the earth to conductor 7473,

  <Desc / Clms Page number 202>

 which extends through the connector circuit shown in Figs.



  73 and 74 to the recorder-envcyeur. Conductor 7473 is extended through contact 3 of relay 6704, the coil of relay 6703, resistor 6705, to the battery.



  While operating, relay 6703 causes relay 6700 to trip and also opens the connector start conductor and the holding conductors to the connector, thereby fully releasing the used connector. Releasing the connector interrupts conductor 7473, which was operating relay 6703. This causes relay 6704 to operate in series with relay 6703 through a circuit that includes: battery, coil of relay 6703, coil of relay 6704, contact 3 of relay 6703, contact 1 of relay 6710, and earth. While operating, relay 6704 establishes a circuit to again operate relay 6700, which includes, the battery, its winding, contact 5 of relay 6704, contact 1 of relay 6710, and ground.



  A power-on circuit which is the same as previously described to re-enter a free marker is now established for the connector. This is usually a different marker from the previously entered marker, since a delay circuit is employed in the marker which prevents the second seizure from occurring in a short period of time. This delay circuit is established by the delayed triggering of the time-counting relays which keeps the relay 5104 for a determined time. Relay 5104 holds relay 5105 through an obvious circuit and relay 5105 holds relay 5003 to place a busy earth on the marker that has just been released.

   This occupant earth is established from earth on relay 5003 by conductor 7498 which keeps connector relays, such as 7401, energized during this time.

  <Desc / Clms Page number 203>

 and maintains the marker in the busy state. After a connector is entered, the relays are actuated in the marker to indicate that a recorder-sender has entered the marker for a second attempt.

   As relay 6704 is activated in the recorder-sender, it is created in a different state of affairs from that which existed during the first test, since the earth is connected to conductor 7461 by contact 2 of relay 6704, the contacts of the connector 7304 and 7405 to actuate relays 5806 and 5807 in the marker to indicate a second try to the marker. The main difference in the marker between the first and the second trial is an arrangement to make use of a different coupling and connector circuit to associate the marker with the crossbar switches.

   One will recall that it was given as an example, on the first try, a connection. coming from an odd recorder-sender and that the relay 5101 was actuated to guide the marker as previously described during its operation, the latter being associated with an odd-numbered recorder-sender. By operating on the second try, relay 5807 changes the order of the selection, activating relay 5102 through conductor 5928 since an odd recorder-sender is still associated with the marker. With relay 5102 actuated and a link desired to outgoing junctions of the same rack, in accordance with the original routing, the marker now chooses the rack connector circuit shown in FIG. 26 instead of the rack connector shown in FIG. 25.

   The operation of the connector shown in FIG. 26 is substantially the same as the operation previously described, except that the coupling relays 2601 and 2602 are actuated to extend the conductors from the marker through the

  <Desc / Clms Page number 204>

 corresponding track up to the switchgear in Fig. 15, so that the junctions located on the same switch frame can be reached. The differences between the operation of the local channel and the corresponding channel have been described previously and therefore it is believed that this description provides an understanding of the operation of the arrangement shown in Fig. 26.



  These differences are minimal and reside particularly in the inversion of the conductors in the marker and in the connector, to energize the relays of the corresponding channel instead of the relays of the local channel when a link is established during the second attempt.



   If the marker fails to establish the link again, it will wait in the same way as previously described, which eventually links the earth to conductor 7473 which will now cause relay 6703 to trigger. this relay was activated after the first marker failure to properly establish the connection with the desired outgoing trunk.



  After the second failure, the earth connected to relay 7473 extends via internal contact 3 of relay 6704, to place a shunt on the winding of relay 6703. This relay no longer receives current from the battery via resistor 6705. and therefore triggers. On tripping, this latter relay establishes an operating circuit for relay 6709, which includes: battery, coil of relay 6709, contact 1 of relay 6703, contact 1 of relay 8704, and earth. While operating, relay 6709 connects earth to conductor 6720, to actuate relay 6604 to release the recorder-sender.



  While operating, relay 6604 connects earth to the coil of relay 5600. remember that relay 5608 was operated from earth on contact 6 of relay 5505 and relay 6504 was operated from earth

  <Desc / Clms Page number 205>

 on relay 5608 by contact 3 of relay 6603.



   As a result, a circuit is now established comprising: battery, winding of relay 5600, contact 1 of relay 5601, contact 1 of relay 5602, contact 4 of relay 6503, contact 3 of relay 6604, and the earth. When operating, the 5600 relay triggers the triggering of the position relays and the triggering of the position relays causes the release of the recorder-sender device.



   Dump.



   In some cases, if all the junctions extending to a particular office are found to be occupied, and if additional junctions are not provided on a different frame, a group of relief junctions is provided, so that the operator initiating the message and that the cordless operator in this office can be informed that all the junctions of the group tested are temporarily occupied. When this discharge group or sub-group is provided, test leads are extended from the terminal block relay to some of the relays of FIG. 38. These discharge junctions are present on the relays of FIG. 38 in the same way as a normal outgoing junction and are chosen in the same way.

   For example, if the normal group of junctions is made up of junctions 0 to 35, and the discharge subgroup is made up of junctions 36 to 39, in case. junctions 0 to 35 are found occupied, a test of the discharge junctions is made.



  If a discharge junction is found free, it can be assumed that relay 3808 is not actuated and that a circuit for relay 3812 is established in the same manner as described for relay 3810 when a normal outgoing junction was. found free. Thus, a circuit is established

  <Desc / Clms Page number 206>

 by the terminal block relay to enter the free discharge junction and the switches of Figs.



   14 and 15 are directed to associate the through junction with the discharge junction in the same way that their association with an outgoing junction extending to a remote trunk office or a terminating junction in a remote trunk would. local office. A test is performed to determine whether a discharge junction is free or occupied by conductor 4138 in the same manner as for the outgoing junction. Conductor 4138 extends through contact 12 of allocation frame connector relay 4110, contact 5 of terminal block relay 3114, conductor 3147, and discharge relay winding.
1102.

   When this discharge junction is found free, after the apparatus of FIG. 17 has been associated with the discharge junction by conductors 4138 and
3147 in the manner previously described to test an outgoing junction, a low resistance earth is connected from the marker of FIG. 17 to the winding of relay 1102 which causes this relay to operate. The low resistance earth makes the discharge junction occupied for other markers. As soon as the free discharge junction is found, the multi-frequency signaling system indicates the number of the frame on which this junction is located in the same way as described here for a multi-frequency indication of the number of the frame on which a frame is located. normal outgoing junction is found.

   The multi-frequency signaling system would have already transmitted signals to the marker providing the rack position of the primary crossbar switch connected to the calling incoming junction.



   It can be assumed that for this example, the multi-frequency signal from the output frame is transmitted

  <Desc / Clms Page number 207>

 by winding the selector electromagnet 1509 through the conductor 2070. This multi-frequency indication is given by the selector electromagnet of the switch associated with the discharge junction in the same manner as described herein. In response to the indication of the frame number, a frame relay is actuated in the marker in the same manner as previously described. Relays are also actuated to indicate whether the discharge junction is associated with an odd or even frame.

   This establishes circuitry to drive a rack coupling and connector circuit, as shown in Figs. 15, 25 and 26 and a similar connector such as 1420 associated with the incoming frame to test the conductors of the junctors which may be used to connect the switch associated with the discharge junction to the switch associated with the calling incoming junction. Junction switches or conductors are therefore chosen for this use and the secondary incoming switches as well as the primary outlet switches are actuated in the manner previously described for such a connection.



  When the holding electromagnets of the switches are actuated in the previously described manner, the earth is connected to the socket conductor 1558 of the discharge junction from the contact 4 of the relay of the incoming junction 1304 before the low resistance earth of the marker is removed. Thus, the switch hold electromagnets are kept actuated and the discharge junction socket conductor is kept occupied for other markers.



  When the contacts of the switches are closed, a circuit is established to actuate relay 1101 as follows: The battery is extended by its winding and contact 2, the neck conductor 1557, the contacts of the crossbar switches, the conductor of neck

  <Desc / Clms Page number 208>

 
1451 of the incoming junction, the shock coil 1524, the contact 7 of the relay 1304 which is actuated, the conductor 3227, the contact 8 of the coupling crossbar switches 3200 and 3203, the conductor 5553, the contact
9 of relay 5505 which is activated, contact 5 of relay
5609 normal, contact 2 of relay 5507 normal, contact 4 of relay 6601 normal,

   relay contact 2
6611 actuated by the high resistance right winding of relay 5605. Relay 5605 operates in a tracking circuit, but relay 1101 does not operate due to the high resistance of the right winding of relay 5605. It is set an obvious circuit for relay 5606 which blocks to earth through contact
8 of relay 2408 .. While operating, relay 5606 connects earth through the low resistance left winding of relay 5605 to the circuit followed by the winding of discharge relay 1101. Relay 1101 now operates, locks up at ground on the contact of relay 1102 and thus removes the battery from the neck conductor extending through the contact points of the crossbar switches through the two windings of relay 5605. This causes the relay to trip 5605.

   With relay 5605 having tripped and relay 5606 being actuated, an obvious circuit is established for relay 5607 which operates and establishes a circuit through its contact 2 for monitoring lamp 5517. Therefore, the monitoring lamp is switched on. now connected by the neck conductor and contact 2 of relay 1101 to the armature of relay 1103. Since all the junctions of the normal group were found occupied, no earth was connected by the windings of relay 1108 to the battery. It will be remembered that all free outgoing junctions in the normal group associate earth with the socket conductor, such as conductor 3127 shown in the outgoing junction

  <Desc / Clms Page number 209>

 normal of FIG. 16.

   When this junction is occupied, relay 1610 is energized and ground is removed from conductor 3127 extending to the branch jack socket. Therefore, when all the junctions of a group are occupied, this earth is not associated with any of the branch jacks and, since the terminals of the sockets of the branch jacks are connected by the windings of the discharge relay 1108, this relay triggers if all the junctions are occupied.

   The relay 1108 having tripped, a circuit is established to transmit an earth interrupted by the neck conductor 1557 following the counting to the duration of the switch 1107. The relay 1103 remains normal and the relay 1104 is actuated. intermittently by the switch 1107 and, thus the interrupted earth is connected from the contact of the relay 1104 by the rear contact of the relay 1103 and the contact of the relay 1101 to the neck conductor 1557. This interrupted earth is extended by the interjunction junction calling incoming long distance and the circuit followed above to flash lamp 5517 in the position of the cordless long distance operator of this office.

   This attendant interprets the flashing period as an indication that all the junctions of the desired outgoing group are busy. The connection will not be immediately dropped since under ordinary traffic conditions a junction will become free in a short period of time. When a junction in the group becomes free, earth is immediately connected from relay 1610 of the free junction through the coil of relay 1108 which operates. In operation, relay 1108 establishes a circuit for battery relay 1103 through its winding, relay contact 1108, and relay 1101 contact to ground. This transfers the interrupted earth circuit from switch 1107 to

  <Desc / Clms Page number 210>

 the switch 1106 which transmits the interrupts at a different interval from that of the switch 1107.

   Relay 1105 is activated according to the interruption period of switch 1106 and transmits ground intermittently through the internal contact of relay 1103, to neck conductor 1557. The change in flashing period indicated on lamp 5517, was noticed by the operator without cords. A second attempt is immediately made by this operator to terminate the call to a free trunk in the desired group of outgoing trunks. In this case, the code of the group of outgoing junctions is re-entered on the keypad by the operator without leads, the same marker or a different marker is entered and the junctions of the group are tried again to attempt. to find a free junction, an attempt which is usually successful under ordinary traffic conditions.

   When no free trunk is available for an extended period of time, the operator initiating the call is notified and a record for a delayed call is filled out. In this case the call can be directed by the long distance operator without cords, to an operator position in the call order table in the usual way.



  * Release of the marker.



   -----------------------
The operating path for the marker release relay 1901 is closed by a contact of relay 4004 when the latter relay trips. Relay 4004 circuit is opened by releasing the primary incoming selector electromagnet and secondary outgoing selector electromagnet, when connection circuits have been fully established by the incoming and outgoing connector circuits. output associated with cross-bar switches of the different frames.

   Therefore-

  <Desc / Clms Page number 211>

 when the marker cannot return to rest and initiate the release of the associated connectors including the frame connectors, until the maneuvers occurring in the frame connectors have established certain operating circuits extending to the marker which are formed as following . Recall that relay 1802 was actuated from earth on contact 1 of relay 2513, in the coupling and output connector circuit, and that relay 1603 was actuated from earth on a rear connector relay. - vee similar to relay 2513.

   During the test of the socket conductors and the holding electromagnets to verify the double connections, earth is applied to the different conductors from contact 1 of relay 1712 which bypasses the operating winding of the connection test relay double 1709. When all of the holding electromagnets have operated and both sets of tip and neck conductors have been closed, the 1712 shine operates, which establishes the operating circuit for the 1714 relay which can be followed as follows: the battery, the winding of the relay 1714, the contact 10 of the relay 1802, the contact of the relay 1712, the conductor 1723, the contact of the relays 5105 and 5107, the conductor 5123, the contact 3 of the relay 1902 and earth .

   While operating, relay 1714 removes the shunt from relay 1709 and removes solid earth from the junction conductor socket. Relay 1709 is now connected to the junction conductor socket in series with the holding electromagnets. If there are no double connections as indicated by the absence of earth on the junction conductor socket, the relay 1709 operates in series with the maintenance electromagnets and at the same time keeps the hand electromagnets - yours actuated.

   When operating, relays 1709 and 1714

  <Desc / Clms Page number 212>

 operate relay 1715 qani locks up and removes ground from conductor 7472, extending through the marker connector to the coil of relay 6601, causing relay 6601 in the recorder-sender to trip.



  This applies a holding earth to the electromagnets of the sockets through its contacts and the incoming junction circuit as previously described. This application of the earth to the socket conductor bypasses the previously actuated relay 1709 and causes the operation of the relay 1711 by a circuit comprising: contact 3 of relay 1715, contact 5 of relay 1714, conductor 6140, con / tact 7 of relay 6101, contact 1 of relay 3810, contact of relay 3814, conductor 3125, as previously followed, allocation frame, conductor 3126, outgoing junction socket, extending through contact points of the output frame crossbar switch, conductor 1570, and earth in the marker.

   When operating, relay 1/14 opens the circuit for relays 1521 and 1524 in the output connector and likewise in the input connector. Likewise, the relay 1714, when it operates, interrupts, by opening its contact 2, a circuit for the output selector electromagnet 1510 and interrupts, by opening its contact 3, its circuit; for the arrival primary selector electromagnet 1405. When triggering, relays 1521 and 1524 open the circuit extending through conductor 25 to the marker relays and similar relays in the arrival connector open, triggering , the circuit extending through conductor 1925. The circuit originally established by conductor 2545, operated relays 4012 and 4004.

   A similar circuit from the incoming connector was established for the 1925 conductor to the left winding of the relay

  <Desc / Clms Page number 213>

 
4004 and the winding of relay 4010. Interruption of conductors 2545 and 2925 triggers these relays. Since relay 1709 is now normal, and relays 1715 and 1711 are actuated, a circuit is established to operate the marker release relay 1901.

   The circuit for the 1901 release relay comprises: the battery, its winding, the conductor 1910, the contact 1 of the relay 6806, the contact 4 of the relay 4004, the conductor 4058, the contact of the relay 1741, the contact 1 of the relay. relay 1715, the contact of the double connection test relay 1709, the conductor 1813, the contact 7 of the relay 6808, and ground. By means of these various paths, the operation of the release relay 1901 indicates that the connection has been properly established. Relay 1901 is blocked by conductor 1910 which forms a branch of conductor 6827, contact 1 of relay 6806, conductor 6828 and in multiple, by contacts of relays 1804, 1801, 1802 and 1803, to earth on its own contact 2.

   This blocking ring is provided to ensure that the release relay remains actuated until the various extra normal earthing relays, and frame relays have tripped ..;. While operating, the release relay 1901 opens the operating circuit for the ground relay 6808. This relay, however, is kept actuated by its earth block circuit on the relay 7304 and does not trip until the circuit. fired from marker connector has come back to rest.



  A circuit is now established to operate the recorder-sender release relay 6711, which extends from the battery through its winding, lead 7447, marker connector relays 1704 and 7405, contact 4 of the relay 1902, contact 1 of the marker release relay 1901, the driver

  <Desc / Clms Page number 214>

 6812 and contact 8 of relay 6808 to earth. When operating, recorder-sender release relay 711 opens the blocking circuit extending through conductor 7451, marker connector relay windings 7304 and 7301: ground.

   This causes tripping of these connector relays and when tripping, relay 7304 opens the circuit for relay 7402, which, when tripping, opens the circuit for relay 7405. Relay 6808 which was blocked BY contact 3 of the relay 7402 to earth on contact 5 of relay 7304, now trips. On triggering, relay 6808 opens the marker relay circuit including relays 1903 and 1904 which provide battery and ground to the marker gear and to the gear which operates the frame connector.

   When tripping, relay 1903 removes the start battery of relays, preferably from frame connectors such as 2522, and from a preferably similar relay in the inlet manifold, causing the relay to switch back. circuits rest. The allocation rack connector also receives battery from relay 1903 and therefore trips.



  The connector circuits that have returned to the normal state are now available to be picked up by other markers and, upon returning to idle, the marker removes its land of occupancy and is therefore available to be associated with other markers. recorder-senders circuits to establish further links. The operation of the recorder-sender release relay 6711 and the disconnection of the marker from the recorder-sender causes the device to be released from the recorder-sender after the recorder-sender has accom- modated. fold all its functions.

   The release relay is located vis-à-vis the digital equipment of the recorder-sending device so as to keep the recorder-sending

  <Desc / Clms Page number 215>

 operated until pulses have been transmitted from the recorder-sender to an output recorder-sender, when an outgoing junction has been chosen to an office requiring pulses for the operation of its equipment. When the pulses have been transmitted from the incoming recorder-sender to the outgoing recorder-sender, the return to idle of the inbound recorder-sender takes place.



   CLAIMS
1. Telephone system comprising a telephone office, lines ending in the office, automatic switches, a control device, a device for indicating to the control device a desired connection by a line with another line, characterized. by a signaling system located in the office for transmitting signals to the control device, which represent the position of the switches which will be engaged in the desired link, and a device in the control device responding to the signals to actuate switches individuals in order to connect said line to said other line.


    

Claims (1)

2. System according to claim 1, characterized in that the signaling system comprises a device for transmitting the signals in the form of combinations. 3. System according to claim 1 or 2, characterized in that the signaling system successively signals the position of a switch connected to the calling incoming line and the position of a switch connected to the outgoing line. desired and resets the controller between successive signals. 4. System according to one or other of claims 1 to 3, characterized by electromagnets for actuating <Desc / Clms Page number 216> the switches, the signaling system having circuit paths, extending through the windings of the electromagnets of the switches to signal the position of the switches. 5. System according to claim 4, characterized in that the response device establishes circuits operating by the windings of the electromagnets to actuate the switches. 6. System according to any one of the preceding claims, characterized in that the control device is a marker common to all the switches. 7. System according to any one of the preceding claims, characterized in that the signaling system comprises circuits and electrical apparatus for transmitting currents of different frequencies. 8. System according to claim 7, characterized in that the response device is selectively actuated according to a particular combination of the frequencies transmitted. 9. System according to any one of the preceding claims, characterized in that the telephone office is an automatically switched long distance office forming part of a telephone network which further comprises several connection offices among which there are several. 'other interurban offices and other offices located in the local area of the switching interurban offices, the automatic switches being arranged in two: trains in the automatic switching interurban office, one train being assigned to calls for remote long distance offices and the other train to calls within said local area. 10. System according to claim 8, characterized in that the two sets of automatic switches com- <Desc / Clms Page number 217> taking incoming switches mounted on a number of frames and output switches mounted) on 11. System according to claim 9 or 10, characterized in that the lines consist of incoming lines going from the connecting long distance offices to the automatic switching long distance office and of outgoing lines going to the connecting long distance offices and to the offices located in the long distance office. local area. 12. System according to any one of claims 9 to 11, characterized in that the transmission signals representing the positions of the switches are direction records serving to automatically establish links by one or the other. other of the switch trains following the recordings. 13. Telephone network comprising an automatically switched interurban office, a number of connection offices comprising other interurban offices and other offices located in the local area of the interurban switching office, two switch trains in the automatically switched long distance office, one train for calls to remote long distance offices and the other train for calls to offices located in the local area, incoming lines from the connecting long distance offices to the long distance office to automatic switching of outgoing lines going to intercity connection offices located in the local area, characterized by a marker common to both sets of switches to control the operation of the switches and by a device in the marker responsive to line selection direction records to automatically establish links through one or the other. another of the switch trains following the records. <Desc / Clms Page number 218> 14. Network according to claim 13, characterized by a signaling system for indicating to the marker the position of the switches engaged in a link and by a device in the marker for actuating said switches. 15. Network according to claim 13, characterized in that the signaling system is a multiple frequency signaling system, comprising a device for using electric currents of different frequencies for the different switch positions and a device for transmitting. the marker identification frequencies. 16. A telephone network system comprising a telephone office, a number of apparatus racks, automatic switches connected to junctions for establishing telephone communications, the junctions and associated switches being mounted on a certain number. number of different frames in preferred groups and in secondary groups, a control device, a device in the control device to try the preferred cranes in vae to find a free junction, characterized by a signaling system arranged to transmit different signals, in order to direct the operation of the control device, a device in the signaling system for directing the control device to a free preferred junction, when the latter is found, and a device in the signaling system for directing the controller to drop the preferred group of junctions on a frame and try a second group of junctions on a different frame in the directions communicated to it, when the junctions of the preferred group are all occupied. 17. System according to claim 16, characterized by a device in the signaling system for indicating the position of the frame of the secondary group when a -218- <Desc / Clms Page number 219> junction of the latter group is found free. 18. System according to claim 16 or 17, characterized in that the signaling system is a multiple frequency signaling system, arranged to transmit different combinations of several current frequencies. 19. Telephone network comprising a telephone office, lines terminating in the office, a number of automatic switches located at different places to connect between it, some lines, a control device, a device for recording in the device for controlling two lines which must be connected to each other, characterized by a signaling system with multiple frequencies to indicate the switches which must operate in order to connect the two lines comprising electrical circuits and apparatus, making it possible to transmit currents of different frequencies to the control device and to the device in the control device actuated by the particular frequencies transmitted to control the operation of the switches as indicated to connect the recorded lines together. 20. The network of claim 19, characterized in that the device in the controller comprises tuned apparatus responding only to the frequencies transmitted to identify the particular switches required to establish the interconnection. 21. Network according to claims 18 or 19, characterized in that the switches consist of incoming switches mounted on several racks used for incoming calls on the lines and of output switches mounted on several racks, used for. outgoing calls on the lines, the control device being a marker, and the signaling system indicating the position of the frames of the necessary switches.