JP3401819B2 - Recording and playback device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording / reproducing apparatus suitable for slow reproduction of a recording / reproducing apparatus for recording a video signal and converting an audio signal into a PCM and further compressing the signal for recording. The present invention relates to a recording / reproducing device capable of slow reproduction without the audio signal being deviated.

[0002]

2. Description of the Related Art Conventionally, a recording / reproducing apparatus known as 8 mm video converts an audio signal into a PCM signal,
The M digital audio signal is compressed on the time axis and recorded on the magnetic tape together with the video signal. FIG. 2 shows an example of such a track format of 8 mm video, and FIG.
Shown in.

In FIG. 2, reference numeral 25 is a magnetic tape on which video signals and audio signals are recorded, and a plurality of recording tracks T,
... are formed. For each recording track T,
Reference numeral 26 is a video recording track on which a video signal is recorded, 27 is a PCM recording track on which a PCM audio signal is recorded, and 28.
Indicates an audio recording track in which the AUX audio signal is recorded in the longitudinal direction of the tape. Reference numeral 29 denotes a video signal reproducing head PB- tracing the recording track T as described in FIG.
A position 30 indicates the position of the PCM audio signal reproducing head PCM-A when the video signal reproducing head 29 is at the position shown in the figure.

In FIG. 3, 29 and 31 are video signal reproducing heads PB-A, PB-B, 30, 32 which are arranged opposite to each other.
Is arranged in front of the video signal reproducing heads 29 and 31, and is also opposed to the PCM audio signal reproducing head PC.
M-A, PCM-B, 33 and 34 are recording heads REC-A, REC-B, and 35 which are arranged to face each other.
The rotation erasing heads FE and 36 arranged earlier are rotary drums on which these heads 29 to 35 are provided.

Next, a description will be given of an operation when recording / reproducing is performed in the track format of FIG. 2 with reference to FIG. The magnetic tape 25 shown in FIG. 2 runs from the right to the left in the drawing, and the recording heads 33 and 34 are provided on a rotary drum 36 which rotates diagonally upward left on the tape.
The video signal and the PCM audio signal are recorded on the track erased by the rotation erasing head 35 arranged further ahead by alternately using the recording heads 33 and 34. As shown in FIG. 2, the video signal is recorded in about 180 degrees of one track, and the PCM audio signal is recorded in the remaining about 36 degrees of one track. A signal is recorded alternately on each recording track with an azimuth angle, and the rotary erasing head 35 is configured to erase two tracks at the same time.

Next, the reproducing operation will be described. When the video signal reproducing head PB-A29 is at the position shown in FIG.
As will be described later, the PCM audio signal reproducing head PCM-A
30 is arranged so as to be at the position shown in the figure, which is preceded by about 2.3 fields. Similarly, the PCM audio signal reproducing head 32 is also arranged so that it can be reproduced about 2.3 fields ahead of the video signal reproducing head 31.

FIG. 4 shows frequency allocation of signals recorded on the recording track shown in FIG. In FIG. 4, 41 is a tracking pilot signal composed of four frequencies for controlling tracking, 42 is a low-frequency-converted carrier color signal, 43 is an FM-modulated audio signal,
Reference numeral 4 is a luminance signal, and 45 is a PCM audio signal. The luminance signal 44 and the PCM audio signal 45 are in almost the same recording band, but the luminance signal has a wider bandwidth.

Each track T shown in FIG. 2 has one of four frequencies of the tracking pilot signal 41.
One pilot signal 41 is superposed and sequentially recorded, and the fact that the pilot signals of the tracks on both sides are recorded at different frequencies is used so that the detected crosstalk of the pilot signals from both sides becomes equal. Tracking control is performed by controlling the head trace.

FIG. 5 shows an example of a recording system for recording on the recording track shown in FIG. In this figure, 51 is a Y / C separation circuit for separating a video signal into a luminance signal Y and a carrier color signal C, 52 is an FM modulation circuit for FM-modulating the luminance signal, and 53.
Is an adder circuit for adding the FM-modulated luminance signal and the low-frequency-converted carrier color signal, 54 is a mixer for low-frequency converting the carrier color signal, and 55 is a carrier for low-frequency converting the carrier color signal. A crystal oscillator, 56 is a crystal oscillator that sets the oscillation frequency of the oscillator 55, 57 is an AD converter that converts a voice signal into a PCM signal, and 58 is a PCM voice signal that is compressed on the time axis and an error correction code is added. And a PCM processing circuit for converting into a predetermined block signal.

Further, 59 is an adding circuit for superimposing a tracking pilot signal on a recording signal, 60 is an ATF signal generating circuit for generating a tracking pilot signal, 61-
A and 61-B are recording amplifiers for amplifying recording signals, and SW
5-1 is connected to the A contact during the period for recording the video signal (the period for which the recording head traces the track shown in FIG. 2 by about 180 degrees) and for the period for recording the PCM audio signal (the track shown in FIG. 2 is about 36 degrees). Period during which the recording head traces) b
Switches connected to the contacts, REC-A and REC-B, are recording heads for recording video signals and PCM audio signals, 6
Reference numeral 2 is a video signal input terminal, and 63 is an audio signal input terminal.

In the recording system shown in FIG. 5, the video signal input to the terminal 62 is separated into a luminance signal and a carrier color signal by the Y / C separation circuit, and the separated luminance signal is F by the FM modulator 52.
It is M-modulated to have a spectrum in a band as shown in FIG. On the other hand, the separated carrier color signal is applied to the mixer 52 and low-frequency converted into a band centered at about 743 kHz to form a low-frequency spectrum as shown in FIG. The FM-modulated luminance signal and the low-frequency-converted carrier color signal are added by an adder 5
3 is added and connected to the a contact of the switch SW5-1.

The audio signal input to the terminal 63 is A
The -D converter 57 converts the PCM signal into a PCM signal, and the converted PCM signal is applied to the PCM processing circuit 58. P
In the CM processing circuit, the PCM signal is time-compressed, and digital processing such as adding an error correction code for correcting an error during reproduction is performed. The frequency spectrum of the PCM audio signal has almost the same band as the frequency spectrum of the luminance signal, but is narrower than the frequency bandwidth of the luminance signal.

The digitally processed PCM audio signal is applied to the b contact of the switch SW5-1. The switch SW5-1 is for the recording heads REC-A and REC-B.
2 is connected to the contact a side during the time of tracing the video recording track shown in FIG. 2, and the recording heads REC-A, REC
-While B is tracing the PCM audio signal recording track, it is connected to the contact b side. Therefore, the video signal and the PCM audio signal are recorded on the recording track as shown in FIG.
Recording is performed alternately by the two recording heads REC-A and REC-B.

Next, FIGS. 6 (a) and 6 (b) show a reproducing system for reproducing the signal thus recorded. FIG. 6A shows a reproducing system for reproducing a video signal, and in this figure, P
BA and PB-B are video signal reproducing heads for reproducing a video signal from a recording track, and 3-A and 3-B are reproducing heads P.
An amplifier for amplifying the video signal reproduced by B-A and PB-B, 5 is a high pass filter (HPF) for extracting a luminance signal from the video signal, and 6 is an FM demodulator (FM demodulator for FM demodulating the FM modulated luminance signal ( FM DEMOD).

Further, 7 is a low-pass filter (LPF) for extracting the signal from the video signal, 8 is a mixer for returning the low-pass-converted carrier color signal to the original band centered at 3.58 MHz, and 9 is the carrier color. A crystal oscillator that generates a carrier for returning the signal to the original frequency band, 10 is a crystal oscillator for oscillating the oscillator 9 at a stable frequency, and 11 is an automatic device for removing jitter of the reproduced carrier color signal. A phase control circuit (APC), 12 is an adder that adds the FM demodulated luminance signal and the carrier color signal returned to the original frequency band to a video signal, and 13 outputs a reproduced video signal This is the output terminal that Further, 20 is an automatic tracking adjustment circuit (ATF) which extracts the tracking pilot signal reproduced from the video signal reproducing heads PB-A and PB-B and outputs the tracking signal, 21 is an amplifier for amplifying the tracking signal, and 22 is A capstan motor that is tracking-controlled so that the head traces a recording track, SW1 is a video signal reproducing head PB-A,
It is a switch for selecting and extracting one of the reproduced video signals from the amplifier 3-A or 3-B in order to obtain the video signal reproduced by PB-B as a continuous video signal.

FIG. 6B shows a PCM audio signal reproduction system. In this figure, PCM-A and PCM-B are PCM.
The audio signal reproducing heads 4-A and 4-B are P reproduced by the PCM audio signal reproducing heads PCM-A and PCM-B.
An amplifier for amplifying the CM audio signal, and 14 is a reproduced PC
When the M audio signal is extended to the original length,
A PCM inverse processing circuit for performing error correction, 15 is a D / A converter for converting a PCM voice signal into an analog voice signal, 16
Is an output terminal for outputting a reproduced analog audio signal,
SW3 is a PCM audio signal reproducing head PCM-A, PCM
-The PCM audio signal reproduced by B is a continuous PC
In order to obtain the M audio signal, the amplifier 4-A or 4
-A switch for selecting and extracting one of the reproduced PCM audio signals from B.

Next, the operation of the reproducing system shown in FIGS. 6A and 6B will be described. Video signal reproducing heads PB-A, PB-
The video signal reproduced by B is the amplifier 3-A, 3-B.
After being amplified by, one video signal is selected by the switch SW1 and output so that the reproduced video signal is continuous. From the output video signal, the HPF 5 extracts a luminance signal having a high frequency spectrum as shown in FIG. 4, and the LPF 7 extracts a carrier color signal having a low frequency spectrum as shown in FIG. The FM-modulated luminance signal output from the HPF 5 is demodulated to the original signal applied to the FM demodulator 6 and applied to the adder 12. Further, the low-frequency-converted carrier color signal output from the LPF 7 is returned to the original band when it is applied to the mixer 8 and applied to the adder 12.

Since the carrier color signal represents the chromaticity by the phase shift and the color jitter is conspicuous, the jitter of the carrier color signal is removed by the automatic phase control circuit 11. The automatic phase control circuit 11 removes the jitter of the carrier color signal by comparing the phases of the carrier color signal output from the mixer 8 and the stable frequency signal output from the crystal oscillator 9. Then, the adder 12 adds the luminance signal and the carrier color signal into a video signal, and the video signal is output from the output terminal.

The output from the switch SW1 is also applied to the tracking automatic adjustment circuit 20, and the video signal and P
The tracking pilot signal recorded by being superimposed on the CM audio signal is extracted. Then, the tracking automatic adjustment circuit 20 adjusts the capstan motor 22 so that the crosstalk of the pilot signals from the tracks on both sides becomes the same.
Is controlled so that the head traces on the recorded track.

On the other hand, PCM audio signal reproducing head PCM-
The PCM audio signals reproduced by A and PCM-B are amplified by amplifiers 4-A and 4-B, and then one of the PCM audio signals is selected and output by the switch SW3 so that the PCM audio signals are continuous. The output PCM audio signal is PC
The time-compressed PCM signal applied to the M inverse processing circuit 14 is time-expanded into a PCM audio signal having the original length. Further, the P reproduced by the PCM reverse processing circuit 14
The CM signal is corrected by the error correction code to obtain a correct PCM voice signal. This PCM audio signal is a D / A converter 1
5 is converted into an analog audio signal and output terminal 1
An audio signal is output from 6.

The head PCM for reproducing the PCM audio signal
-A is, for example, 2.3 from the video signal reproducing head PB-A.
The PCM audio reproducing head PCM-B is also arranged 2.3 fields ahead of the video signal reproducing head PB-B. The reason for this will be described below with reference to FIGS. 7 and 8.

In FIG. 7, (a) is a waveform of a voice signal,
In the figure, (b) is the waveform of the audio signal sampled in the T ₁ time width, (c) is the digitally processed PCM audio signal in the T ₂ time width, and (d) is the reproduced PCM audio signal in the T ₃ time width. , (E) shows the audio signal digitally inversely processed in the T ₄ time width. 8, (a) is a video input signal for each field, (b) is an audio input signal for each field, (c) is a video signal reproduced by a video signal reproducing head, d) is an audio signal reproduced by the video signal reproducing head, and (e) in the figure is an audio signal reproduced by the audio signal reproducing head arranged in advance.

From the audio signal shown in FIG. 7A, for example, T
An audio signal of ₁ hour width is taken out as shown in FIG. 7B, and an audio signal sample of T ₁ time width is A-D converted to P.
Convert to CM signal. And this PCM of T ₁ time width
When the audio signal is time-compressed to the T ₂ time width shown in FIG. 7C, time is spent on the digital processing, and the time P is P for the time T _5.
CM signal is delayed. This delayed PCM audio signal is recorded on the tape as shown in FIG. 8 (b).

The recorded PCM audio signal of the T ₂ time width is reproduced as a PCM audio signal of the T ₃ time width as shown in FIG. 7 (d). This played PC of T ₃ time width
The M audio signal is expanded to the T ₄ time width shown in FIG. 7E, and then converted into an analog audio signal by the DA converter to be a reproduced audio signal. However, time is spent for this digital inverse processing, and the audio signal is further delayed, and eventually the audio signal is reproduced with a delay of time T ₆ shown in FIG. 7E. This state is shown in FIG. That is, when also reproduced audio signal by using the video signal reproducing head, about corresponds to the time T _6, as shown in FIG. 8 (d) 2.
The audio signal will be reproduced with a delay of only three fields.

However, since there is no delay element in the video signal recording / reproducing system, the video signal is not delayed even when reproduced as shown in FIG. 8C, and the image displayed when the audio signal is output as it is is displayed. The sound is delayed as compared with, and the image and the sound do not match.

Therefore, if the PCM audio signal reproducing head is arranged prior to the video signal reproducing head and the audio delay is compensated by reproducing the audio in advance, the preceding degree of the PCM audio reproducing head is shown in FIG. As can be understood from (c) and (d), it may be about 2.3 fields. Therefore, as shown in FIG. 2, the PCM audio reproducing head PCM
-A leads the video signal reproducing head PB-A by about 2.3 fields.

[0027]

The recording / reproducing apparatus is generally provided with not only a normal reproduction mode for reproducing at a normal speed but also a slow reproduction mode, a fast-forward reproduction mode, etc., for editing a tape. With these features, accurate editing is achieved. In addition, as a means for accurately detecting the editing position of the tape when editing the tape, generally, the slow playback mode is set, and by listening to the sound played back slowly, the exact editing point (frame number, time code) of the tape can be detected. ) Is guessing the position.

However, as shown in FIG.
When the M audio signal reproducing heads PCM-A and PCM-B are arranged in advance of the video signal reproducing heads PB-A and PB-B by about 2.3 fields, the audio signal is reproduced as shown in FIG. 9 during slow reproduction. However, there is a problem in that the editing position cannot be accurately detected by playing back too fast and listening to the audio signal.

This will be described with reference to FIG. FIG. 9 shows 1/10 slow playback, and in this figure, (a)
Is a video signal reproduced by the video signal reproducing head, FIG. 7B is an audio signal reproduced by the video signal reproducing head, and FIG. 9C is an audio signal reproduced by the preceding audio signal reproducing head. is there.

When 1/10 slow reproduction is performed, the tape running speed becomes 1/10, and the video reproducing head scans one track 10 times. Therefore, FIG.
As shown in (a), one-field video signals V ₀ , V
Reproduce ₁ and V ₂ 10 times each. Similarly, PC
M audio signal reproducing head is also PCM audio signals A ₀ , A
₁ and A ₂ are reproduced 10 times each, but the audio reproducing head is arranged ahead of the other, so that FIG.
As shown in (1), the PCM signal reproduced by the preceding head reproduces the sound 23 fields ahead on the time axis as compared with the timing when the PCM signal is reproduced by the video signal reproducing head.

As a result, the audio signal is about 2 times more than the video signal.
Since 0.7 fields are output in advance, the editing point, for example, the start point of the video signal V ₁ can be accurately grasped by the output point of the audio signal A ₁ by listening to the audio signal for the editing position of the tape. could not. Therefore, it is an object of the present invention to reproduce an audio signal and a video signal in time with each other during normal operation and to reproduce an audio signal and a video signal with each other in time during slow reproduction. .

[0032]

In order to achieve the above-mentioned object, the present invention obtains an audio signal from an audio signal reproducing head arranged in advance during normal reproduction, and from a video signal reproducing head during slow reproduction. And a voice signal.

[0033]

In normal reproduction, since the audio signal is obtained from the audio signal reproducing head arranged in advance, the video signal and the audio signal coincide with each other in time. Further, since the video signal and the audio signal are obtained from the video signal reproducing head during the slow reproduction, the audio signal is slightly delayed from the video signal, and the editing position of the tape can be sufficiently detected by listening to the audio signal. It will be possible.

[0034]

FIG. 1 shows an embodiment of the reproducing system of the recording / reproducing apparatus of the present invention. In this figure, PB-A and PB-B are video signal reproducing heads for reproducing video signals from the recording tracks PB-A and PB-B, and 3-A and 3-B are for amplifying video signals reproduced by the reproducing heads. An amplifier, SW1 is a switch for extracting a video signal reproduced from the video signal reproducing head as a continuous video signal, 5 is a high-pass filter (HPF) for extracting a luminance signal from the video signal, and 6 is an FM modulated luminance. FM demodulator (FM
DEMOD).

Further, 7 is a low-pass filter (LPF) for extracting the carrier color signal from the video signal, and 8 is a mixer for returning the carrier color signal subjected to the low frequency conversion to the carrier color signal centered at 3.58 MHz. Reference numeral 9 is a crystal oscillator for generating a carrier for returning the carrier color signal to the original frequency band, 10 is a crystal oscillator for oscillating the crystal oscillator 9 at a stable frequency, and 11 is jitter of the reproduced carrier color signal. An automatic phase control circuit (APC) for removing the signal, an adder 12 for adding the FM demodulated luminance signal and the carrier color signal returned to the original frequency band into a video signal, and 13 for a reproduced video It is an output terminal for outputting a signal.

PCM-A and PCM-B are PCM audio signal reproducing heads, and 4-A and 4-B are PCM audio signal reproducing heads PCM-A and PC reproduced by PCM-B.
Amplifier for amplifying M audio signal, 14 is reproduced PCM
A PCM inverse processing circuit that restores the original length of the audio signal when it is time-expanded and performs error correction, 15 is a DA converter that converts the PCM audio signal into an analog audio signal, and 16 is a reproduced analog signal. Output terminal for outputting the audio signal of S
W2 is a switch for taking out the PCM audio signal reproduced by the video signal reproducing heads PB-A and PB-B as continuous PCM audio, and SW3 is the PC reproduced by the PCM audio signal reproducing heads PCM-A and PCM-B.
In order to obtain the M audio signal as a continuous PCM audio signal, a switch for selecting and extracting the reproduced PCM audio signal from the amplifier 4-A or 4-B, SW4 is connected to the contact b side during normal reproduction and The switch is connected to the contact a side during reproduction.

Numeral 20 is a PCM audio signal reproducing head P
A tracking automatic adjustment circuit (ATF) that extracts the tracking pilot signal reproduced from the CM-A and PCM-B and outputs the tracking signal, 21 is an amplifier that amplifies the tracking signal, and 22 is for the head to trace a predetermined position. A tracking-controlled capstan motor 23 is a system control circuit that connects the switch SW4 to the contact b side during normal reproduction and to the contact a during slow reproduction, and disables the amplifier 21.

The operation of the reproducing system shown in FIG. 1 during normal reproduction will be described. During normal reproduction, the switch SW4 is connected to the b contact side by the normal reproduction signal of the system control circuit. Then, the video signal reproducing head PB-A,
The video signal reproduced by the PB-B is the amplifier 3-A,
After being amplified by 3-B, one video signal is selected by the switch SW1 and output so that the reproduced video signal is continuous.

A luminance signal having a high frequency spectrum as shown in FIG. 4 is extracted from the output video signal by the HPF 5, and a carrier color signal having a low frequency spectrum as shown in FIG. 4 is extracted by the LPF 7. To do. The FM-modulated luminance signal output from the HPF 5 is demodulated to the original signal applied to the FM demodulator 6 and applied to the adder 12. The low-frequency-converted carrier color signal output from the LPF 7 is returned to the original band when applied to the mixer 8,
It is applied to the adder 12.

The carrier applied to the mixer 8 is supplied from the automatic phase control circuit 11, and the automatic phase control circuit 11 outputs the phase of the carrier color signal output from the mixer 8 and the stable frequency signal output from the crystal oscillator 9. The carrier color signal from which the phase jitter of the carrier color signal has been removed is output from the mixer 8. The carrier color signal from which the jitter has been removed and the luminance signal are added by the adder 12 into a video signal, which is output from the output terminal 13.

On the other hand, PCM audio signal reproducing head PCM-
The PCM audio signals reproduced by A and PCM-B are amplified by amplifiers 4-A and 4-B, and then one of the PCM audio signals is selected and output by the switch SW3 so that the PCM audio signals are continuous. The output PCM audio signal is PC
The time-compressed PCM signal applied to the M inverse processing circuit 14 is time-expanded into a PCM audio signal having the original length. Further, the P reproduced by the PCM reverse processing circuit 14
The error of the CM signal is corrected by the error correction code and the correct P
It is used as a CM audio signal.

This PCM voice signal is converted into an analog voice signal by the DA converter 15, and the voice signal is output from the output terminal 16. The PCM audio signal reproducing head PCM-A is arranged, for example, 2.3 fields ahead of the video signal reproducing head PB-A. Similarly, the PCM audio reproducing head PCM-B is also arranged as the video signal reproducing head PB-B.
It is placed 2.3 fields ahead of the others.

The reproduction output from the switch SW3 is also applied to the automatic tracking adjustment circuit 20, and the tracking is controlled by using the tracking pilot signal recorded by being superimposed on the video signal and the PCM audio signal. In tracking control, by controlling the capstan motor 22 so that the crosstalk amount of the pilot signal leaking from both adjacent tracks to the currently traced track becomes the same, the head traces accurately on the recorded track. I am able to do it.

For this reason, as shown in FIG. 2, four different low frequencies are prepared as tracking pilot signals, and pilot signals of four frequencies are sequentially recorded on different tracks. Further, the tracking pilot signal is reproduced by using the PCM audio reproducing heads PCM-A and PCM-B which have a relatively large gap as compared with the video signal reproducing heads PB-A and PB-B and are suitable for reproducing low frequency signals. Therefore, the tracking pilot signal can be efficiently reproduced.

Next, when the mode is set to slow reproduction,
The system control circuit 23 outputs a slow reproduction signal, connects the switch 4 to the a contact side, and deactivates the amplifier 21 so that the capstan motor 22 is not controlled by the automatic tracking adjustment circuit 20.
Then, the audio signal reproduced by the video signal reproducing heads PB-A and PB-B is input to the PCM inverse processing circuit 14, and the audio signal output terminal 16 outputs the video signal reproducing heads PB-A and PB-B. The reproduced audio signal shown in FIG. 9B is output. Then, at the time of 1/10 slow reproduction, both the PCM audio signal and the video signal are output from the video signal reproducing heads PB-A and PB-B 10 times each, so that it is clear with reference to FIGS. 9 (a) and 9 (b). As described above, there occurs a period in which the video signal and the PCM audio signal are reproduced so as to match in time.

Therefore, during slow reproduction, the reproduced audio signal is about 2.
Since it is only delayed by 3 fields, the editing work which was difficult to edit by listening to the audio signal reproduced 20.7 fields earlier by the PCM audio signal reproducing head arranged earlier is described in FIG. In the recording / reproducing apparatus shown in (1), it becomes possible to sufficiently edit the tape by listening to the audio signal.

[0047]

Since the present invention is constructed as described above, during normal reproduction, the audio signal is obtained from the audio signal reproducing head arranged in advance, so that the time between the video signal and the audio signal is equalized. You can play it back. Further, since the video signal and the audio signal are obtained from the video signal reproducing head during the slow reproduction, the audio signal is slightly delayed from the video signal, and the tape editing work can be sufficiently performed by listening to the audio signal. .

Further, since the tracking pilot signal is reproduced by using the PCM audio reproducing head suitable for reproducing the low frequency signal, the tracking pilot signal can be reproduced efficiently and the tracking control can be surely performed. .

[Brief description of drawings]

FIG. 1 is a diagram showing a recording / reproducing apparatus of the present invention.

FIG. 2 is a diagram showing a tape format of a recording / reproducing apparatus.

FIG. 3 is a diagram showing a head arrangement of a rotary drum of the recording / reproducing apparatus.

FIG. 4 is a diagram showing a recorded frequency spectrum of the recording / reproducing apparatus.

FIG. 5 is a diagram showing a recording system of a recording / reproducing apparatus.

FIG. 6 is a diagram showing a reproducing system of a conventional recording / reproducing apparatus.

FIG. 7 is a diagram showing a process of processing a PCM audio signal.

FIG. 8 is a diagram showing a reproduction state of a PCM audio signal and a video signal during normal reproduction.

FIG. 9 is a diagram showing a reproduction state of a PCM audio signal and a video signal during slow reproduction.

[Explanation of symbols]

3-A, 3-B Video signal amplification amplifier 4-A, 4-B PCM audio signal amplifier 5 HPF 6 FM demodulator 7 LPF 8 Mixer 9 Crystal oscillator 10 Crystal oscillator 11 Automatic phase control circuit 12 Adder 13 Video signal output terminal 14 PCM reverse processing circuit 15 DA converter 16 Audio signal output terminal 20 Tracking automatic adjustment circuit 21 Amplifier 22 Capstan motor 25 Magnetic tape 26 Video signal recording track 27 PCM audio signal recording track 28 AUX audio signal recording Tracks 29, 31 Video signal reproducing heads 30, 32 PCM audio signal reproducing heads 33, 34 Recording head 35 Rotation erasing head 36 Rotating drum 41 Tracking pilot signal 42 Carrier color signal 43 FM audio signal 44 Luminance signal 45 PCM audio signal 51 Y / C separation circuit 52 FM modulator 53, 59 Calculator 54 Mixer 55 Crystal oscillator 56 Crystal oscillator 57 A-D converter 58 PCM processing circuit 60 ATF signal generation circuit 61-A, 61-B Recording amplifier SW1, SW2, SW3, SW4, SW5-1 Switch PB- A, PB-B Video signal reproducing head PCM-A, PCM-B PCM Audio signal reproducing head REC-A, REC-B Recording head FE Rotation erasing head

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Claims (3)

(57) [Claims] 1. A compressed PCM audio signal is recorded on a part of a track, a video signal is recorded on the remaining track, and the recorded PCM audio signal is preceded by a video signal reproducing head to a rotary drum. In the recording / reproducing apparatus which reproduces the video signal by the PCM audio signal reproducing head disposed in the above, and reproduces the video signal by the above-mentioned video signal reproducing head, P
A recording / reproducing apparatus characterized in that a CM audio signal is also reproduced. 2. A P reproduced from the video signal reproducing head.
A switch for switching between the CM audio signal and the PCM audio signal reproduced by the PCM audio signal reproducing head is provided, and the PC from the video signal reproducing head during slow reproduction is provided.
2. The recording / reproducing apparatus according to claim 1, wherein the switch is switched so that the M audio signal is selected. 3. The recording / reproducing apparatus according to claim 1, wherein the PCM audio signal reproducing head reproduces a tracking pilot signal recorded on the track so as to be superposed on the track for tracking control.