JPS6286501A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To execute the correct recording and reproducing even when the inclining track is divided into plural channels and used by recording the control signal and executing the timing control only when the first channel is recorded. CONSTITUTION:At the time of recording, changing-over switches 49a and 49b are fallen down to an M side and a changing-over switch 48 is set to the desired channel. The signal from an input terminal 40 is A/D-converted by a recording processing circuit 41, further, the time compressing operation is executed by the control of a timing control circuit 47 and outputted through a changing-over switch 34a to rotary heads A and B. The switch 34a is set to an R side at the time of recording, set to a P side at the time of others by the output of the circuit 47, the presence and the absence of the reproducing output are discriminated by a reproducing signal presence/absence discriminating circuit 46, and when the output is not executed, the control signal is recorded only to the first channel by a control head C. At the time of reproduction, switches 34a-34c are forcibly to the P side, the control signal is reproduced and the recording and reproducing is correctly executed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rotary head type magnetic recording/reproducing device arranged and reproduced.

[Conventional technology]

Figures 5 to 7 are diagrams related to conventional magnetic recording and reproducing equipment, and in Figure 5, fil is a rotating head drum;
Are W and tBl angles of 1800 to each other? Accordingly, the rotary head +21 arranged on the rotary head drum (1) was wound approximately 1800 mm around the VC thread on the rotary head drum (11), and was made to run in the direction of the arrow in the figure. The magnetic tape (IC) has a control head for recording or reproducing a tracking control signal at the end of the magnetic tape (2), and (3) a cap for transporting the magnetic tape (2). Figure 6 is a schematic diagram of the magnetic pattern recorded on the magnetic tape (2), and the diagonal trunks in the figure are the tracks recorded with the rotating head and IB). The track indicated by the symbol A was recorded by the rotary head, and the track indicated by the symbol B was recorded by the rotary head +Bl. The magnetic pattern indicated by the symbol C is the control head IC.
It was recorded in I.

FIG. 7 is a block diagram showing the main parts of a recording and reproducing system for reproducing signals from such a magnetic tape, in which the magnetic pattern shown in FIG. , 3υ is the recording processing circuit, device is the recording amplifier, - is the signal output terminal, (to) is the reproduction processing circuit, (to) is the reproduction amplifier, measurement is the reference signal input terminal, and the same is the control signal recording circuit. , (C) is the capstan control circuit, 4 is the capstan rotation detector, the figure is the capstan drive motor, 6X1
is the rotating head drum control circuit, (to) is the rotating head drum rotation detector, (to) is the rotating head drum drive motor,
(8+a), (34b), and (s+c) are recording/reproduction changeover switches, R indicates a recording side contact, and P indicates a reproduction side contact. A (or B) and C are the same as those shown in FIG. 5, and are a rotating head and a control head, respectively.

Next, the operation will be explained. First, the operation during recording will be explained.

If the input signal marked on the signal input terminal is a television video signal here, the video signal is sent to the recording processing circuit and undergoes signal processing suitable for recording on magnetic tape, such as FM modulation. After being processed, this FM signal is applied to a recording amplifier @ to amplify it to the appropriate level. The output of the recording amplifier 14 is applied to the rotary head and tBl via the contact R of the changeover switch ($4a).

On the other hand, the reference signal input terminal is input with a 1$ signal that is used to brake the rotation of the capstan or rotary head drum. Input the frequency-divided signal as a reference signal. A part of this reference signal is guided to the rotating head drum control circuit 6υ, where this signal is compared with the rotation pulse derived from the rotating head drum rotation detector, and a comparison output is generated based on this phase comparison. The rotary head drum drive motor GIJk is controlled by.

As a result, the head drum (1) rotates while being locked to the reference signal. In addition, a part of the above reference signal is connected to the capstan, [t
l1m circuit, and here, this signal and the capstan rotation detector 4 are connected to the changeover switch (34C) contact Rt-
The phase is compared with the rotational pulse guided through the capsun, and the capsun drive motor is controlled based on the comparison output based on this phase comparison. As a result, the cabtan (3) also rotates while being locked to the reference signal, and the magnetic tape (2) runs at a predetermined speed.Furthermore, a part of the reference signal is applied to the control signal recording circuit gradient, where the appropriate waveform is After being molded, it is led to the control head (q) via the contact Ri of the changeover switch (84b).

As described above, the video signal is recorded as diagonal recording tracks A and B as shown in FIG. 6 by the rotary heads A and B alternately by one file and at a constant trunk pitch, while the control signal C is Every two fields are recorded on the control track at the end of the tape with equal pinch as shown in FIG.

Next, we will focus on the operation during playback.

A reference signal having a frequency approximately equal to the same wave number of the sufficiently repeated vertical synchronizing signal at the time of recording is applied to the reference signal input terminal. This reference signal /'i--an oscillation signal of a stable crystal oscillator is always used. A portion of the reference signal is directed to the rotating head drum control circuit υ. Here, the rotary head drum III rotates while being locked to the reference signal in exactly the same manner as described in the above-mentioned recording operation.

Further, part of the reference signal is applied to the capstan control circuit. The other input to the capstan control circuit is different from that during recording, and the control signal recorded at the end of the magnetic tape (21) is reproduced from the control head C1 and the changeover switch ω4b and (84c) are input. Contact P
Introduced via. The capstan control circuit μs compares the phases of the reference signal and the reproduction control signal inputted in this manner, and controls the capstan drive mode mt based on the comparison output. As a result, the traveling phase of the magnetic tape (21c) is locked to the reference signal, and the rotating head prisoner and tBl alternately move on the tracks indicated by symbols A and B on the magnetic tape. Correct tracking is performed by the IBI and the video signal is reproduced, and this reproduced signal is transmitted through the contact P of the changeover switch (8+a).
Guided by regenerative intensifier (To).

The playback signal amplified on the playback amplifier side undergoes playback processing [Kawa, 6
w<, and after being subjected to processing such as FM demodulation, the original video signal is sent to the output terminal.

Signal recording and reproduction are performed in the manner described above. To summarize, the structure is such that diagonal tracks ft are recorded by a rotating magnetic head, one control signal is recorded for every two diagonal tracks at the same time, and the signal is reproduced by tracking the rotating head using the control signal as a cue during playback. I'm so happy to be done.

[Problem that the invention seeks to solve]

Conventional magnetic recording and reproducing devices are configured as described above, so the diagonal signal recording tracks are replaced with audio tracks, and each track is divided into, for example, five channels, and the valley channels are divided into five channels. If you try to time-compress an audio signal and record it, if you record the aforementioned control signal at the end of the tape each time you record to each channel, it will be impossible to determine which control signal corresponds to which channel during playback. Therefore, there was a problem that correct tracking could not be performed.

This invention was made in order to solve the above-mentioned problems, and it is possible to record and play back correctly even if the inclined track is divided into multiple channels and used to record audio signals instead of video signals. The overall purpose is to obtain a recording/reproducing device.

[Means for solving problems]

A magnetic recording/reproducing device iL according to the VC of the present invention is provided with a timing control circuit that generates a timing signal indicating a predetermined channel among a plurality of channels divided into a tilted track of a magnetic tape in the fixed direction of a rotary head. To record and reproduce the corresponding part of the inclined track corresponding to a predetermined channel in synchronization, and furthermore, record a control signal only when recording the first channel on the magnetic tape, and when recording the next channel, Tracking is performed using previously recorded control signals.

[Effect]

In the magnetic recording/reproducing device of this invention, since the timing control circuit is fully functional, it is possible to correctly specify the channel during recording and reproduction, and select the first channel. A control signal is recorded only when recording, and this control signal is used for tracking from the recording of the next channel, so it is possible to have multiple channels in one trunk? Even if provided, the tracking control of the existing magnetic recording/reproducing device can be used as is without adding any amount of confusion to the control signal.

[Embodiments of the invention]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings, applying it to the case of recording and reproducing audio signals.

In Fig. 1) is a signal input terminal, and (6) is a signal input terminal for compressing the input signal to -J, for example, 3, and recording it in the part 4 while the rotary head makes a half rotation while melting the tape. 4 is a recording processing circuit that performs signal processing; 4 is a recording amplification circuit for amplifying the time-compressed signal created by 1υ to an appropriate level; Processing [a reproduction signal processing circuit for performing the opposite effect to the bribe o1, that is, extending the reproduction signal for the entire time and restoring it to the original signal;
%) is a reproduction amplifier that amplifies the signal reproduced from the rotating head. %■ is a circuit that determines the presence or absence of a reproduced signal. The reproduced signal from the rotating head is detected by, for example, an envelope, and if there is a reproduced signal, it is set to a high level ( 1 () output, if there is no playback signal, the full low level (L) output will be output.
- The circuit operates based on the signal from the rotation detector (2) of the TO1 rotation head drum based on the signal of $1. (9) is a channel setting switch for setting a recording or reproduction channel.

(49a) and (491)) are changeover switches, and when recording time compression No. 18, the contact point is set to M. ”
~(84a)s (34b), (84c) and A-
Cd are the same as in FIG. 7, respectively.

Next, the operation will be explained.

First, we will discuss the case of recording time-compressed signals '+'i on magnetic tape for the first time.
and (49b) collapse to i M fil. Also, at this time, change the selector switch @8 to the desired channel, e.g.
Set to HI, input terminal, MJVC signal to be recorded,
In addition, a reference signal is input to the input terminal/lees. The rotating head drum control and capstan control operate in exactly the same way as described in the conventional example, and will be briefly explained again.

For the capstan, the selector switch (84c) is set to R.
When it is on the side, the magnetic tape is controlled to run at a constant speed by locking to the reference signal and rotating, and when the changeover switch (84): +) and (84C) are on the P position, the magnetic tape is The running of the magnetic tape is controlled so that the reproduced control signal is locked to the reference signal.

On the other hand, the rotating head drum is controlled so that it always rotates while being locked to the reference signal.

To explain this situation with reference to Fig. 4, iGl in Fig. 4 is a reference signal, and (Fl is a signal in which the entire rotational pulse obtained from the rotating head drum rotation detector Q is schematically reflected). This schematic rotational pulse fFl is at the riH level, the rotational head +
It is adjusted so that it is at the L level while L is in contact with the magnetic tape and rotates for half a rotation.

Now, the input terminal Tochi has r! For example, -gAJ of a 0° input signal to which an audio signal is applied is shown in Fig. 4 tAIVC. This signal is impressed on the road 11)] road 14]), and ζO
Analog to digital conversion (%) fx etc., POM
A time compression operation is performed by increasing the reading speed of the memory circuit compared to the reading speed of the memory circuit. The timing of the time compression signal output from the recording processing circuit 4)) is determined by the timing control circuit θη shown in FIG.
Controlled based on the signal shown at D+, in this case cal
It is output at the timing that corresponds to KMJ. The output of the time compressed signal at this time is shown in FIG. 4 tBl and fcl VC. This output is amplified by a recording amplifier and guided to a changeover switch (84a). The changeover switch (84a) is switched to the R side in synchronization with the timing of the time compression signal by the output of the d timing control circuit 1, so the time compression signal 8 is guided to the rotating head and connected to the rotating head prisoner and IBI.
Recording is performed alternately on the magnetic tape. As mentioned above, the output of the timing control circuit α is switched to the changeover switch (84a) all R side only at the timing to record CHl, but at other times, the output of the changeover switch (84a) i
Switch to P side. P+X! When the switch is switched to I, the playback output from the rotating head surface and IBI will be guided to the playback amplifier and amplified. Since there is no Vc/i regenerative output, the output of the regenerative amplifier μs is zero. The output of the regenerative amplifier is guided to the reproduced signal presence/absence discrimination circuit and subjected to envelope detection.In this case, since there is no reproduction output, the output of the above discrimination circuit is at L level as shown in Figure 4 (El). This output is applied to the changeover switches (84b) and (84c) via the M contact of the changeover switch (49b), and all of the contacts thereof are set to the R side.

As a result, the capstan rotates while being locked to the reference signal, and at the same time, a control signal synchronized with the reference signal is recorded from the control signal recording circuit fin onto the magnetic tape by the control head (q).This situation is shown in Figure 4. Shown in (6).

As described above, a time-compressed audio signal is recorded in the electrically divided portion of the diagonal trunk described above, here indicated by CH1 as shown in FIG. 2, and a control signal is recorded at the end of the tape. is recorded.

Next, a case will be described in which another signal is recorded on an empty channel of a tape on which a certain channel, for example CH1, has already been recorded. Switch villQ is set to OH2, for example, to apply all the signals to be recorded to the input terminal Q, and input all the same reference signals as mentioned above to the input terminal example. In this case as well, the operation of the trough is almost the same as described above, but the output of the timing control circuit (B) does not have the timing shown in Figure 4 (D'). Switch -) Switch to gold R side 0 Also, the output obtained from the recording connection circuit outputs a time compression signal in the period corresponding to OH2 based on the output of the timing control circuit α force 〇 On the other hand, other than the period corresponding to OH2 above Since the changeover switch (34a) is set to the P side, the outputs of the rotary head and IBI are guided to the regenerative amplifier (except during the period JH2). If there is a recorded part in any channel, a signal output is obtained from the reproduction amplifier (G), and this is applied to the reproduction signal presence/absence determination circuit wr■, resulting in the H level output shown by the dotted line in Fig. 4 fEl. occurs. This H level output allows the selector switch (
8+b) and (84c) are switched to the P side.

The capstan is thus controlled by the reference signal and the previously recorded control signal, so that another time-compressed signal is recorded on the continuation of the previously recorded diagonal track. This situation is shown as OH2 in FIG.

The same can be considered when recording CH3, OH4, and OH5f.

FIG. 3 shows how all channels are recorded in this way.

This is just like a signal input terminal and recording processing (ol).
Five channels are provided in parallel for each channel, and time compressed signals with different timings for each channel are created for each track.
ftt, Figure 4 (B') and (C) The signal train is created and recorded on the entire diagonal track in the same way as in the case of conventional video signal recording, and the corresponding control signal is It can be considered to be equivalent to something recorded at the same time.

When reproducing a signal recorded as described above, first, changeover switches Cs4a), Cs+b), and (84C) are forcibly turned to the P side, and changeover switch 4 is turned to the desired channel. At this time, the capstan and rotary head drum are controlled in the same way as in the conventional example, and correct tracking is performed.The signals reproduced between the rotary heads and from the IBI are amplified by a reproduction amplifier), and then the reproduction processing circuit − is applied.

In the timing control circuit (1), the time compressed signal of the desired channel is selected by the output of the timing control circuit (1), and is further time-expanded to restore the original signal to obtain the desired signal at the output terminal.

In the above embodiment, the input signal? Although it has been explained as an audio signal, other signals may be used.

Furthermore, in the above embodiment, the tape was fed in the same direction for recording on both CH2 and CH2, but the tape is fed in reverse on one of the channels, for example, CH1, CH3, O.
Alternatively, H5 may be sent in the forward direction and CH2 and CH4 may be recorded as backwards.

〔Effect of the invention〕

As described above, according to the present invention, the structure is such that a common control signal can be used for a plurality of channels divided into all the inclined trunks, so the tape format of the conventional device can be used as is, and the tracking can be performed using the conventional circuit. Since it can be used, the device can be manufactured at a low cost, and there is an effect that an air recording and reproducing device that can perform highly accurate recording and reproducing can be obtained.

[Brief explanation of drawings]

@Figure 1 shows a magnetic recording/reproducing device gL according to an embodiment of the present invention.
A complete block diagram, FIGS. 2 and 8 are diagrams showing magnetic patterns recorded by the embodiment column VC of the present invention, FIG. 4 is a waveform diagram for explaining the operation of the embodiment of the present invention, and FIG.
FIG. 6 is a configuration diagram showing the relationship between the rotary head and control head in a magnetic recording/reproducing device and a magnetic tape, and FIG. 6 is a diagram showing a magnetic pattern recorded by a conventional device.
FIG. 7 is a block diagram showing a conventional device. In the figure, A and B [rotary head, C is control head s
C8+h), Cs+b), (s+a)ri selector switch, ni)li, playback double number and j separate 11? The circuit, θη, is a timing-based circuit. In the figures, the same reference numerals indicate the same - or (g).

Claims (5)

[Claims] (1) Tracks that are inclined with respect to the running direction of the magnetic tape are sequentially formed and recorded adjacent to each other by a plurality of rotating heads, and recorded signals on the inclined tracks are reproduced by the plurality of rotating heads, and the recorded signals are recorded on the magnetic tape by a fixed head. In a magnetic recording and reproducing apparatus that tracks the magnetic tape by forming and recording a continuous control track in the running direction of the magnetic tape and reproducing the recorded control signal of the control track using a fixed head, the inclined track is scanned by the rotary head. a timing control circuit that generates a timing signal indicating a predetermined channel among the plurality of channels divided in the direction; and a timing control circuit that switches the rotary head to the recording side in synchronization with the predetermined channel of the timing signal, and switches the rotating head to the recording side, If the corresponding part of the inclined track corresponding to the channel has not been recorded yet, the fixed head is switched to the recording side, and if the corresponding part of the inclined track corresponding to the channel other than the predetermined channel has been recorded, the fixed head is switched to the recording side. A magnetic recording/reproducing device comprising: a switching means for switching a magnetic recording device to a reproducing side; (2) The magnetic recording and reproducing apparatus according to claim 1, wherein the timing control circuit generates a timing signal in synchronization with the rotation signals of the plurality of rotary heads. (3) The switching means includes a first switch that switches the rotary head to the recording side in synchronization with a predetermined channel of the timing signal, and switches the rotary head to the playback side during other channel periods, and a first switch that switches the rotary head to the playback side in synchronization with a predetermined channel of the timing signal; A discrimination circuit detects the presence or absence of a recorded signal, and if this discrimination circuit detects the absence of a recorded signal, it switches the fixed head to the recording side, and if it detects the presence of a recorded signal, it switches the fixed head to the reproduction side. 2
2. A magnetic recording and reproducing apparatus according to claim 1, further comprising a switch. (4) The rotary head and the constant head are switched to the reproduction side, and the recorded signal reproduced by the rotary head is extracted in synchronization with a predetermined channel of the timing signal. Magnetic recording and reproducing device. (5) A magnetic recording and reproducing apparatus according to any one of claims 1 to 4, characterized in that a rotary head records and reproduces an audio signal on each channel of an inclined track.