US1336414A - Telegraphy - Google Patents

Telegraphy Download PDF

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Publication number
US1336414A
US1336414A US249812A US24981218A US1336414A US 1336414 A US1336414 A US 1336414A US 249812 A US249812 A US 249812A US 24981218 A US24981218 A US 24981218A US 1336414 A US1336414 A US 1336414A
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US
United States
Prior art keywords
relay
relays
contacts
impulse
conductor
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US249812A
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English (en)
Inventor
John H Bell
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
AT&T Corp
Original Assignee
Western Electric Co Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to US203032A priority Critical patent/US1386679A/en
Priority to US210148A priority patent/US1379243A/en
Application filed by Western Electric Co Inc filed Critical Western Electric Co Inc
Priority to US249812A priority patent/US1336414A/en
Priority to GB1970919A priority patent/GB142375A/en
Priority to FR503295A priority patent/FR503295A/fr
Priority to GB2115919A priority patent/GB155877A/en
Priority to FR21735A priority patent/FR21735E/fr
Priority to FR22611A priority patent/FR22611E/fr
Application granted granted Critical
Publication of US1336414A publication Critical patent/US1336414A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/18—Phase-modulated carrier systems, i.e. using phase-shift keying
    • H04L27/24—Half-wave signalling systems
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T17/00—Component parts, details, or accessories of power brake systems not covered by groups B60T8/00, B60T13/00 or B60T15/00, or presenting other characteristic features
    • B60T17/04—Arrangements of piping, valves in the piping, e.g. cut-off valves, couplings or air hoses
    • B60T17/043—Brake line couplings, air hoses and stopcocks
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00—Baseband systems
    • H04L25/38—Synchronous or start-stop systems, e.g. for Baudot code
    • H04L25/40—Transmitting circuits; Receiving circuits
    • H04L25/49—Transmitting circuits; Receiving circuits using code conversion at the transmitter; using predistortion; using insertion of idle bits for obtaining a desired frequency spectrum; using three or more amplitude levels ; Baseband coding techniques specific to data transmission systems

Definitions

  • This invention relates to telegraph systems and more particularly to cable or submarine telegraphy.
  • the principal object ofthis invention is to provide an improved organization of apparatus-to prevent so-called wandering-zero effects in telegraph conductors having high electrostatic capacity characteristics.
  • FIG. 1 of the drawing a transmitting equipment which may correspond with one arm or section of a'multiplex equipment and is arran ed for use in connection with one channe of a multiplexed line.
  • Fig. 2 there is shown an equipment for transmission over a second channel of the same line conductor and this equipment differs from the equipment shown in the first figure only in that devices common to the cable or line conductor are also included in this figure.
  • the present invention therefore contemplates that in addition to providing that the cable may be grounded during impulse intervals which may correspond with successive repetitions of like current polarities, a system for controlling many different current potentials may be so arranged that following a period during which the cable may have been grounded, the value of a next succeeding impulse may be of such modified strength as to prevent an undue building-up and charging efiect in the cable.
  • this potential varying'system provides that for successive impulses of inverse polarities the strength of the currents may be the same.
  • a single fold reduction of potential may become effective with the nextsucceeding impulse of opposite polarity, and when an impulse follows two impulse intervals during which the cable may have been grounded, current having a two-fold reduction in potential will form such impulse.
  • a third, fourth, fifth, or more, reduction of the line current potentials may be effected after third, fourth, fifth, or more consecutive impulse intervals, respectively, during-which the cable may have continued grounded.
  • the equipment of the first multiplex channel shown in Fig. 1, comprises automatic contact levers 15 which will be understood as arranged in a manner adapted for control by a suitably notated or perforated transmitting tape.
  • these contacts control the operation of pole changer relays 1115 which determine the polarity of currents employed in signaling.
  • Relays 21-25 connected to be controlled through respectively adjacent ones of the transmitting contact levers 15 serve for normally grounding a cable L (Fig. 2) and for connecting this cable to receive current as selected by the pole changer relays 11-15.
  • pole changer relays 1115 which determine the polarity of currents employed in signaling.
  • grounding relays 21-25 also serve with current potential control relays 31-35 in rendering resistance units 146-150 effective to suitably vary the potential of the line currents which may have been selected, these resistances being further under control of a master relay 140, connected to form a series common to the operating circuit of each relay comprising the group 31-35.
  • current protective or limiting resistances are included in the leads through which current is supplied to the cable, and the current modifying resistances are, at proper moments, connected to serve in parallel or bridge from the cable. conductor to earth,-thereby constituting a path or paths in parallel with the cable for deflecting a portion of the line current therefrom. Since in the Baudot code which, for
  • each character selecting group is formed of permutations of five successive impulses of opposite polarities
  • the reference characters A, C, D and E have been employed and positioned to respectively correspond with successive ones of five impulse intervals.
  • the equipment positioned directly below these reference characters and set off by the vertical guide lines correspond with the devices associated with the respective impulseperiods.
  • the transmitting contact 1, relays 11, 21 and 31, and distrib-- uter segments 41, 51, 61, 71 and 81 correspond with this first impulse interval of a character selecting series
  • transmitter contact 2, relays 12, 22 and 32, and distributer segments 42, 52, 62, 72 and 82 correspond with a second impulse interval, this order continuing as indicated by the reference characters C, D and E for the last three impulse periodsfof a series.
  • the equipment shown in 2 of the drawing corresponds with a second channel of the duplex equipment, and the arrangement of the local devices is the same as the arrangement alread. described in connection with the first gure. Briefly enumerated, this equipment comprises transmitting contacts 6-10, pole changer relays 16-20, grounding'relays 26-30, potential control relays 36-40, master relay 160 and potential varying resistances 166-170 partially controlled by this relay.
  • Therreference-characters F, G, H, I and J serve respectively to designate the equipment directly associated with impulse intervals corresponding with five character selectin impulse periods for this second channel.
  • a first polar relay 112 is arranged to respond to prepared line currents .and'operates in polarity unison with such currents.
  • This relay servesas a holding or locking relay for retaining energized any one ofthe potential control relays 31-40 which may have been operated in either one of the two distributer sections.
  • a second polar relay 116 is connected to be controlled by currents applied to the cable L, its connective relation being such that the movement of its armature will always be in opposite phase with respect to the polarity of the operating impulses and the relation of the connections from oppositely poled lines batteries 104 and 108 as established with its contact stops.
  • resistances 146-150 and 166-170 to the line batteries
  • the relay 116 therefore connects these resistances to the battery having potential opposite to the line battery from which the relay may have last received its operating current.
  • this distributer may be of a suitable rotary type in which brushes 126 and 127 may traverse their respective paths from left to ri ht over the segments-of the two channels (Big. 1 and Fig. 2).
  • the brush 126 on arriving in the zoneA, serves to join the se cuts 41, 51 and 61, while in zone B it joms the segments 42, 52 and 62, and respectively joins corresponding segments as it passes through the successive zones C-J.
  • the segments 41-50 are connected to control the operation of respective adjacent ones of the relays 31-40, while the segments 51-60 are connected in derived circuit relation from the respective line circuit supply leads controlled by the relays 21-30, the segments 61-70 being connected to control the operation of the first polar relay 112. It will be noted that segments 71-80 .as connected to the segments 51-60 respectively, are in an advance relation relative to the latter segments.
  • segment 71 in zone A connects to seg ment 52 in zone B
  • segment 72 in zone B connects to segment 53 in zone 0, this relation continuing respectively through the various zones and is completed where the segment 80 in the last zone J connects to the segment 51 in the first zone A.
  • the segments 81-90 are connected directly to the line or cable L.
  • an energizing circuit for the relay 21 extends from the ne ative bus 102 through the winding of t is relay, thence byway of a conductor120 and the transmitter lever 10 to the positive bus 103.
  • an energizing circuit for the relay 21 extends from the ne ative bus 102 through the winding of t is relay, thence byway of a conductor120 and the transmitter lever 10 to the positive bus 103.
  • the circuit of the second impulse may be traced from a positively poled and grounded battery 107 byway of a resistance .108, bus conductor 109, thence over the forward contacts of the relay 12 and forward contacts of the relay 22 to the segment 72 in zone B and the segment 53 in zone C.
  • the brush 127 joins the positively charged segment 72 to the segment 82 and thereby causes positive energization of the cable Land opposite biasing of the relay 116 to close its contacts 117, over circuits relay 112 and an associated resistance to earth. This polar relay will then assume its negative bias to establish its contacts 114.
  • the brush 126 also causes energization of the segment 42 which is connected through the winding of the relay 31, a bus conductor 124, thence in parallel through the windings of the two master relays 140 and 160.
  • the relays 31, 140 and 160 now operated receive locking current over a circuit which may be traced from a negatively poled and grounded battery 110, the contacts 114 of the polar relay 112, a bus conductor 115, and the right-hand forward contacts of the relay 31.
  • the forward contacts of the relay 23 to energize the segments 73 and 54 therefore, when the brush 127 arrives in the zone C, the cable conductor L will receive a negative impulse of, current, while the brush 126 will establish the positively charged segment 53 with the segment 63 to positively bias the relay 112 to close its contacts 113.
  • the brush 126 joins the segment 53 to the segment 43, thereby energizing the relay 32 and the relays 140 and 160 with current of positive polarity, following which these relays will be retained locked by current from a positively poled and grounded'source 111 which may now traverse the contacts 113 of the relay 112, the bus conductor 115, and the locking or right-hand forward contacts of the relay 32. It will be pointed out that at the instant the relay 112 was last operated to separate its contacts 114,,the negative battery 110 was disconnected from the bus con .ductor 115, thereby permitting the release of the relay 31 and the relays 140 and 160.
  • the fourth impulse, positive current from the bus conductor 109 may traverse the forward contacts of the relays 14 and 24 to energize the segments 74 and 55, therefore on arriving in the zone D, the brush 127 impresses a positive impulse on the cable lead L, while the brush 126 causes the lock control relay 112 to assume its negative bias to separate its contacts 113 and to close itsv contacts 114. Separation of the contacts 113 disconnects the locking battery 111 to release the relays 32, 140 and 160 while the brush 126 also causes the initial operation of the relay 33 and reoperation of the relays 140 and 1.60, which will then continue operated by locking current from the negative battery 110 over circuits corresponding with those already traced.
  • For the fifth impulse current from the negative bus conductor 106 may traverse the normal contacts of the relay 15 and the forward contacts of the rela 25 to energize the segments 75 and 56. n entering the zone E, the brush 127 will accordingly impart a negative impulse to the cable L, while the brush 126 will cause the relay 112 to assume its positive bias, thereby releasing theation of the five impulses already described as having been prepared in the second channel will now be taken up.
  • the brush 126 establishes the positively energized segment 57 to effect positivebias of the relay 112 to separate its contacts 113, thereby disconnecting the relays 35, 140 and 160, while operating the relay 36 and locking it and also'the relays 140 and 160 over the contacts 114 of the relay 112. Since the third impulse is also of positive polarity, the cable will again be grounded in substitution of such current and this grounding may be traced from the cable segment 88 by way of the brush 127 on its arrival in the zone H, segment 78 and the right-hand normal contacts of the relay 28 to the grounded bus conductor 121.
  • the fourth or negative impulse will cause this relay to assume its bias to close its contacts 118, thereby establishing a circuit to modify or reduce the potential of the negative currentwhich may be effective with the line conductor L during this fourth impulse interval.
  • This potential reducing circuit may be traced from the negative bus .conductor 106, contacts 118 of the relay 116,
  • a second circuit may be traced through the resistance 168, the contacts 163 of the relay 160, and the left-hand normal contacts of re lays 28 and 37 respectively. Therefore, it
  • the brush 126 having also arrived in zone J, it establishes the negatively charged segment 60 to bias the relay 112 to separate its contacts 113, thereby releasing the relays 36, 140 and 160; at this time the brush 136 also causes energization of the relays 39, 140 and 160 which will then continue locked through the contacts 11% of relay 112.
  • the last described operation completes the sendingof the five character selecting impulses for the second channel and the circuits prepared by the operation of the relays 39, 140 and 160 may or may not become effective depending on whether following impulse intervals may require grounding of the cable as already described.
  • the relays 35, 1&0 and 160 will be standing locked as operated due to the brush 126 in passing through the zone F; accordingly, a circuit may be traced from the positivebus conductor 109, contacts 117 of the relay 116, the resistance unit 166, contacts 161 of the relay 160, the normal, contacts of the relay 26, a conductor 122 to earth, over the left-hand forward contacts of the relay 35. At this time the other resistances associated with the relays M0 and 160 are rendered ineffective through the separated condition of the left-hand normal contacts of the relays 2225 and 2730.
  • equipment in the first channel may be considered as positioned, as already described, for the transmission of alternate positive and negative impulses beginning with a negative impulse, while the equipment of the second channel will be positioned to transmit three negative impulses followed by a fourth positive impulse and' a fifth impulse of negative polarity.
  • the transmitter levers 2, 1, 6, 7, 8, 10 and relays 12, 14, 1618, 20, 2225 and 29 and 30 will stand operated while the remaining equipment will be positioned as shown in the drawing.
  • the resistance control relays 35, 1 10 and 160 will be operated and continue in that condition until the brushes arrive in the zone 1 when an impulse of positive current will be imparted to the cable.
  • a circuit may be traced from the positive bus conductor 109 by way of the contacts 117 of the relay 116, thence by way of the resistances 166, 167 and 168 to earth at the forward contacts of the relay 35, the circuits for these resistances being respectively completed over the contacts 161, 162 and 163 of relay 160 and the left-hand normal contacts of the relays 26, 27 and 28, by way of conductor 122. At this time all other resistances will stand disconnected at the separated left-hand contacts of the relays 22-25 and 29 and 30.
  • circuits may be further traced over the left-hand normal contacts of the relays 26-29 and the conductor" 122 to earth, over the forward'contacts of the relay 35.
  • the circuit path of the resistance 169 in addition to extending through the'contacts of the relays 26, 27 and 28, also includes the normal contacts of the relays 36, 37 and 38, while, in a corresponding manner, the circuit of the resistanee'168 extends through the normal contacts of the relays 36 and 37, and the circuit of the resistance 167 extends through the contacts of the relay 36.
  • the path for the resistance 148 may be traced through the contacts 143 of the relay 140, thence over the left-hand normal contacts of the relays 23, 32, 22, 31 and 21 to continue over a conductor 123 and the lefthand normal contacts of the relays 40, 30, 39, 29, 38, 28, 37, 27, 36 and 26 and the conductor 122 to ground at the contacts of the relay 35.
  • the routing-of the circuit just traced for the resistance 148 represents the longest path-and it will be noted that the respective circuits of the other resistances may be traced as'extending in joint relationover portions of this circuit.
  • the capacity of the multiplex equipment may be either quadruplex, sextuplex or in accordance with any other of the well-known service capacity arrangements, or the equipment may have the capacity of only a single channel coresponding with the equipment shown in Fig. 2 of the drawing. Therefore, when the brushes 126 and 127-leave the zone J they may proceed through other similar quadrants or channel sections and' at a proper time arrive at and again traverse thedistributer sections of the Figs. 1 and 2 inainanner similar to that already describcd.
  • the multiplex equipment comprises ⁇ only a single channel, as the channel equipment in Fig. 2, the brushes 126 and 127 after leaving the last impulse zone J may immediately reenter the first impulse zone F to again traverse the equipment of this channel.
  • bus conductors 102 and 103 of the battery 101 stand transposed with respect to the transmitting contacts 15 ofthe first channel and the transmitting contact 6-10 of the second channel, while in corresponding manner the line battery bus conductors 106 and 109 also stand transposed with respect to the control contacts of the pole changer relays 11-15 ofthe first channel and the pole changer relays 16-20 of the second channel.
  • the operat ing circuit for the relay 21 may be-traceil from the negative bus conductor 102 over the transmitter lever 1, winding of relay 21, the conductor 120, thence through the transmitter contact lever 10 to the positively poled bus conductor 103, and'in corresponding manner the energizing circuit for the relay 26 may be traced from the negative bus conductor 102 by Way of the transmitter lever 5, a conductor 119, the winding of the relay 26, and the transmitter lever 6 to the positively poled bus conductor 103.
  • the distributer equipment may continue to operate and each time the brushes pass through the first impulse zone A of the first channel, an impulse of negative current will be applied to the cable L, while each time the brushes pass through the first impulse zone F of the second channel, an impulse of positive current will be applied to the cable L.
  • the potential of these impulses will be reduced in a manner similar to that already described in connection with other impulses. This will be clear since grounding of the cable will be effected during the time the brushes are traversing the impulse Zones 13-13 and GJ. To make this clear an inspection of the drawing will reveal that when the brushes have returned to retraverse the impulse zone A the relays 36, 140 and 160 will be locked in their operated positions, thereby permitting a circuit to be traced from the negative bus conductor 106,
  • contacts 118 of relay 116 thence branching jointly through the resistances 167170, the longest circuit for which may be traced through contacts 165 of the relay 160 and through the left-hand normal contacts of the relays 30, 39, 29, 38, 28, 37, 27, thence to earth over the left-hand forward contacts of the relay 36.
  • the other resistances 146-150 and 166 at this time stand disconnected at the left-hand normal contacts of the relays 21 and 26 respectively.
  • the brushes may arrive in the impulse zone F of the second channel, the relays 31, 140 and 160 will be held locked in an energized condition, thereby permitting a circuit to be traced from; the positive bus conductor 109 by way of the contacts 117 of the polar relay 116 to complete branch circuits through the four resistance units 147-150, the longest circuit for these units may be traced from the contacts 145 of the relay 140, thence by way of the left-hand normal contacts of the relays 25, 34, 24, 33, 23, 32 and 22, thence over the left-hand forward contacts of the relay 31 to earth.
  • the resistance unit 146 stands open at the left-hand normal contacts of the relay 21, while the resistance units 166-170 stand open at the left-hand normal contacts of the relay 26.
  • the method of telegraphic transmission which consists in grounding a line conductor in substitution of consecutive impulses oflike polarity and in varying the strength of telegraphic impulses in accordance with a predetermined scale of electrical characteristics controlled bythe duration of the preceding grounded interval.
  • means for the tranu lission of character selecting im ulse combinations formed of permutations o current polarities means for employing intervals ofno current to correspond with periods during which successive impulses of like polarity would 'be repeated, and means for varying the potential of an impulse which may follow such interval of no current.
  • a line conductor means for applying impulses of dill'erent polarity 1n signaling over said line, means tion of periods corresponding with successive repetitions of impulsesof like polarity,
  • a line conductor means for employing currents of opposite polarities in signaling over said line, drainage means for preventing excess charging of said conductor by current of either polarity, and means for modifying the potential of an impulse next following the application of such drainage means to said line conductor.
  • a line conductor means foremploying permutations of current impulses of opposite polarities in signaling over said line, means for'grounding said line in substitution of successive repetitions of impulses of like polarity, and means for rendering the potential of a next impulse of opposite polarity inversely proportional to the length of time such grounding interval may have been efi'ective.
  • a line conductor duplex equipment therefor, sources of current, pole changer means for applying impulses of either polarity from said sources of current to said line conductor, switching means for normally grounding said line conductor, mea-n controlled by said switching means for extending current polarities selected bysaid pole changers, means controlled by said distributer forapplying said extended polarities to said line conductor, potential modifying means for varying the strength of currents supplied to said line, and means controlled by the operation of said distributer for rendering said potential modifying means effective to vary the potential of the currents supplied to said line conductor.
  • a line conductor means for applying currents of predetermined potentials and opposite polarities in signaling over said line, means controlled in the transmission of said impulses to ground said line conductor in substitution of successive impulse intervals of like polarity, and mean controlled in said grounding operations to prepare circuits for diminishing the potential of an impulse to a predetermined degree depending on the number of impulse intervals during which the line conductor may have been grounded preceding the transmission of such diminished impulse.
  • sources of current a line conductor, transmitter contacts for preparing predetermined permutations of polarities from said currents, pole changer relays controlled by said transmitter contacts, current potential modifying relays controlled by said transmitter contacts, distributer means to cooperate with said pole changer relays and said potential modifying relays for applying said selected polarities to said line conductor, a third plurality of relays controlled by said distributer, a plurality of master relays controlled jointly with said third plurality of relays, a polar relay controlled by said distributer for establishing locking of said third plurality of relays and said master relays, resistance units jointly controlled by said master relays and said third relays, a second polar relay controlled by current polarities applied to said line, conducter, and means controlled by said second polar relay to serve jointlywith said master rclays and said potential controlling relays to render said resistances efi'ectivc'to vary the potential of an impulse of either polarity which may be applied to said line conductor.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
US249812A 1917-11-21 1918-08-14 Telegraphy Expired - Lifetime US1336414A (en)

Priority Applications (8)

Application Number Priority Date Filing Date Title
US203032A US1386679A (en) 1917-11-21 1917-11-21 Telegraph system
US210148A US1379243A (en) 1918-01-03 1918-01-03 Telegraph system
US249812A US1336414A (en) 1918-08-14 1918-08-14 Telegraphy
GB1970919A GB142375A (en) 1918-08-14 1919-08-11 Improvements in telegraph systems
FR503295A FR503295A (fr) 1918-08-14 1919-08-28 Perfectionnements dans les systèmes de transmission télégraphique utilisant des conducteurs à haute capacité électrostatique
GB2115919A GB155877A (en) 1918-08-14 1919-08-28 Improvements in electric telegraph systems
FR21735A FR21735E (fr) 1918-08-14 1919-09-16 Perfectionnements dans les systèmes de transmission télégraphique utilisant des conducteurs à haute capacité électrostatique
FR22611A FR22611E (fr) 1918-08-14 1919-10-13 Perfectionnements dans les systèmes de transmission télégraphique utilisant des conducteurs à haute capacité électrostatique

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US249812A US1336414A (en) 1918-08-14 1918-08-14 Telegraphy

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Publication Number Publication Date
US1336414A true US1336414A (en) 1920-04-13

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Application Number Title Priority Date Filing Date
US249812A Expired - Lifetime US1336414A (en) 1917-11-21 1918-08-14 Telegraphy

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US (1) US1336414A (fr)
FR (3) FR503295A (fr)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2527819A1 (fr) * 1982-05-25 1983-12-02 Thomson Brandt Procede d'enregistrement et de lecture par echantillonnage de signaux sonores sur un support magnetique

Also Published As

Publication number Publication date
FR22611E (fr) 1921-08-04
FR503295A (fr) 1920-06-07
FR21735E (fr) 1921-01-12

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