JPH09231678A - Signal reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a signal reproducing device capable of reducing the distortion of reproduced sound due to jitters and noise. SOLUTION: A signal of frequency band where a frequency modulated sound signal exists is separated from an information signal reproduced by a rotary head 8, and this separated signal is demodulated by a 1st demodulating circuit 11. On the other hand, for instance, a horizontal synchronizing signal is sampled from the reproduced information signal by a reproduced reference signal sampling circuit 15, and a voltage signal corresponding to a relative speed between the rotary head 8 and a recording medium 9 is generated from the sampled horizontal synchronizing signal by a detecting circuit 16. Then, the voltage signal generated by the detecting circuit 16 is adjusted in gain and phase by a correcting circuit 17, and is then subtracted from the sound signal demodulated by the demodulating circuit 11, thereby correcting the demodulated sound signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal reproducing device for reproducing an audio signal and a video signal recorded on a recording medium.

[0002]

2. Description of the Related Art Conventionally, there is known a signal reproducing apparatus for reproducing an audio signal and a video signal recorded on a recording medium by tracing a recording medium such as a recording tape with a rotary head or the like. With this signal reproducing device, recording of audio signals,
When a method using a fixed head for reproduction processing is adopted, the relative speed between the recording tape and the fixed head is slow, and there is a limit in obtaining sufficient performance in terms of wow and flutter, the SN ratio of reproduction, or frequency characteristics. In order to record / reproduce an audio signal of higher sound quality, the audio signal is frequency-modulated and recorded on the same track as the video signal.

A conventional signal reproducing apparatus will be described below.

FIG. 4 is a block diagram showing the structure of a conventional signal reproducing apparatus.

In the figure, 1 is an audio input terminal and 2 is a video input terminal. The audio input terminal 1 is connected to the first frequency modulator 3, the video input terminal 2 is connected to the second frequency modulator 4, and the first frequency modulator 3 and the second frequency modulator 4 are connected. The recording amplifier 5 is connected to the output side. A rotary head 8 is connected to the output side of the recording amplifier 5, and the rotary head 8 is in contact with a recording tape 9 when recording / reproducing a signal.

On the other hand, a reference signal extracting circuit 6 is also connected to the video input terminal 2. Switch part is the recording side terminal 1
9, a reproducing side terminal 20 and a switch 21. The recording side terminal 19 is connected to the output side of the reference signal extracting circuit 6, and the reproducing side terminal 20 is connected to the output side of a reference signal generator 18 provided near the rotary head 8. Further, the switch 21 is connected to the input side of the rotation control circuit 7. When recording a signal, the switch 21 is connected to the recording-side terminal 19
On the other hand, the switch 21 contacts the reproducing side terminal 20 during signal reproduction.

A reproduction amplifier 10 is connected to the side from which the signal picked up by the rotary head 8 and the recording tape 9 is output, and the output side of the reproduction amplifier 10 is connected to a first demodulation circuit 11 and a second demodulation circuit 12. It is connected. An audio output terminal 13 is connected to the output side of the first demodulation circuit 11, and a video output terminal 14 is connected to the output side of the second demodulation circuit 12.

When recording a signal, the audio input terminal 1
The audio signal input from the first frequency modulator 3 is frequency-modulated by the first frequency modulator 3, and the video signal input from the video input terminal 2 is frequency-modulated by the second frequency modulator 4, and these signals are recorded together. It is input to the amplifier 5.

The video signal input from the video input terminal 2 is also input to the reference signal extracting circuit 6. At the time of recording a signal, the switch 21 contacts the recording side terminal 19, so that the reference signal extracting circuit 6 is connected to the rotation control circuit 7. In the reference signal extracting circuit 6, the reference signal is extracted from the input video signal, and the reference signal is the rotation control circuit 7
Is input to The rotation control circuit 7 controls the rotation of the rotary head 8 based on the input reference signal so as to be synchronized with the video signal output from the recording amplifier 5, and the rotary head 8 controls the rotation to rotate the recording amplifier 5. The audio signal and the video signal output from are recorded on the recording tape 9. In the case of the rotary head recording system, since one field of a video signal is recorded on one track in most cases, a vertical synchronizing signal is often used as this reference signal. When the audio signal and the video signal are recorded on the recording tape 9, a tracking control pilot signal is recorded as an information signal in which these signals are frequency-multiplexed.

On the other hand, when the signal is reproduced, the switch 21 is in contact with the reproduction side terminal 20, so that the reference indicating the position of the rotary head 8 generated by the reference signal generator 18 provided close to the rotary head 8. Signal is rotation control circuit 7
Will be returned to This reference signal is a reference signal for the rotation of the rotary head 8. Then, the rotation control circuit 7 controls the rotary head 8 based on the fed back reference signal so that the rotary head 8 maintains a constant rotation.

A signal picked up from the recording tape 9 by the rotary head 8 tracing the recording tape 9 is input to the reproduction amplifier 10 and amplified, and an audio signal is input to the first demodulation circuit 11. The video signal is input to the second demodulation circuit 12. The audio signal input to the first demodulation circuit 11 is demodulated and then output via the audio output terminal 13, and the video signal input to the second demodulation circuit 12 is also demodulated and then output via the video output terminal 14. Is output.

[0012]

However, in the above-mentioned conventional signal reproducing apparatus, a change in relative speed between the rotary head and the recording tape (hereinafter referred to as "jitter" due to uneven rotation of the rotary head or expansion / contraction of the recording tape). ") Occurs, and the generated jitter appears during playback.

In the current television broadcasting system, 50 per second
Since the screen or 60 screens are reproduced, and one screen is recorded on one track in the rotary head recording method, when the rotary head has uneven rotation, the frequency of the jitter caused by the uneven rotation is generated. In many cases, the 50-screen system has its higher harmonic component based on 25 Hz, and the 60-screen system has its higher harmonic component based on 30 Hz in many cases. Since these frequencies are in the band of the audio signal, it is annoying if these components are included during reproduction due to uneven rotation of the rotary head.

On the other hand, the same phenomenon occurs when the recording tape expands or contracts. For example, if the recording tape stretched during playback compared to when it was recorded,
Even if the rotary head traces at a constant speed, the change in the reversal of the magnetic field becomes slow, so that the frequency of the reproduced signal becomes low and the above phenomenon occurs.

As described above, the frequency of the reproduced signal is affected by the unevenness of rotation of the rotary head, the expansion and contraction of the recording tape, or the effect of the combination of both.
Since there is a change with respect to the original frequency, there is a problem that waveform distortion occurs in a part of voice and noise occurs in a silent part.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object thereof is to provide a signal reproducing apparatus capable of reducing distortion and noise of reproduced sound caused by jitter.

[0017]

In order to achieve the above object, a signal reproducing apparatus according to claim 1 of the present invention frequency-modulates a video signal and an audio signal into different frequency bands from each other, and then performs the frequency modulation. A signal reproducing apparatus having reproducing means for reproducing the recorded information signal from a recording medium on which an information signal generated by frequency-multiplexing a tracking control pilot signal with a video signal and an audio signal is recorded. A predetermined signal separating means for separating a predetermined signal from the information signal reproduced by the reproducing means, and a signal in a frequency band in which the frequency-modulated audio signal exists from the information signal reproduced by the reproducing means. The audio signal separating means, the audio signal demodulating means for demodulating the signal separated by the audio signal separating means, and the predetermined signal separating means. Generating a correction signal from a predetermined signal demultiplexed I, characterized in that a correcting means for correcting the signal demodulated by the audio signal demodulating means using the correction signals said generated.

In order to achieve the same object, the signal reproducing apparatus according to a second aspect of the present invention is the signal reproducing apparatus according to the first aspect, wherein the frequency modulated video signal is present from the information signal reproduced by the reproducing means. And a video signal demodulating means for demodulating the signal separated by the video signal separating means.

In order to achieve the same object, a signal reproducing apparatus according to a third aspect of the present invention is the signal reproducing apparatus according to the first or second aspect, wherein the reproducing means reproduces the recorded information signal from the recording medium. And a voice signal detecting means for detecting a voice signal from the information signal reproduced by the rotary head, wherein the correcting means stores the recording medium from the predetermined signal separated by the predetermined signal separating means. Change signal detection means for detecting a change signal indicating a change in relative speed with the rotary head, and subtraction means for subtracting the change signal detected by the change signal detection means from the audio signal detected by the audio signal detection means. It is characterized by having and.

In order to achieve the same object, a signal reproducing apparatus according to a fourth aspect of the present invention is the signal reproducing apparatus according to any one of the first to third aspects, in which the predetermined signal is a vertical synchronizing signal. It is characterized by

In order to achieve the same object, a signal reproducing apparatus according to a fifth aspect of the present invention is the signal reproducing apparatus according to any one of the first to third aspects, in which the predetermined signal is a horizontal synchronizing signal. It is characterized by

In order to achieve the same object, a signal reproducing apparatus according to a sixth aspect of the present invention is the signal reproducing apparatus according to any one of the first to third aspects, wherein the predetermined signal is included in the information signal. The signal is not frequency-modulated.

In order to achieve the same object, the signal reproducing apparatus according to a seventh aspect of the present invention is the signal reproducing apparatus according to any one of the first to third aspects, wherein the predetermined signal is a pilot signal for tracking control. Is characterized in that.

In order to achieve the same object, a signal reproducing apparatus according to an eighth aspect of the present invention is characterized in that a video signal and an audio signal are frequency-modulated into different frequency bands, respectively, and then the frequency-modulated video signal and audio signal. A signal reproducing apparatus having reproducing means for reproducing the recorded information signal from the recording medium in which the information signal generated by frequency-multiplexing the tracking control pilot signal is recorded by the rotating head. A predetermined signal separating means for separating a predetermined signal from the information signal reproduced by the reproducing means, and a control signal generated from the predetermined signal separated by the predetermined signal separating means, and the generated control signal And a control means for controlling the rotating operation of the rotary head.

In order to achieve the same object, the signal reproducing apparatus according to a ninth aspect of the present invention is the signal reproducing apparatus according to the eighth aspect, wherein the frequency modulated audio signal is present from the information signal reproduced by the reproducing means. An audio signal separating means for separating a signal in a frequency band to be used, an audio signal demodulating means for demodulating the signal separated by the audio signal separating means,
Video signal separation means for separating a signal in the frequency band in which the frequency-modulated video signal exists from the information signal reproduced by the reproduction means, and video signal demodulation means for demodulating the signal separated by the video signal separation means It is characterized by having and.

In order to achieve the same object, a signal reproducing apparatus according to a tenth aspect of the present invention is the signal reproducing apparatus according to the eighth or ninth aspect, wherein the control means has a predetermined signal separated by the predetermined signal separating means. Feedback control means for feedback-controlling the rotating operation of the rotary head so that the relative speed between the recording medium and the rotary head becomes substantially constant by using a control signal generated from.

In order to achieve the same object, a signal reproducing apparatus according to claim 11 of the present invention is the signal reproducing device according to claim 8 or 9, wherein the control means has a predetermined signal separated by the predetermined signal separating means. Feedback control means for feedback-controlling the rotating operation of the rotary head so as to reduce the change in the relative speed between the recording medium and the rotary head, using a control signal generated from.

In order to achieve the same object, a signal reproducing apparatus according to a twelfth aspect of the present invention is the signal reproducing apparatus according to any one of the eighth to eleventh aspects, wherein the predetermined signal is a vertical synchronizing signal. It is characterized by

In order to achieve the same object, a signal reproducing apparatus according to a thirteenth aspect of the present invention is the signal reproducing apparatus according to any one of the eighth to eleventh aspects, wherein the predetermined signal is a horizontal synchronizing signal. It is characterized by

In order to achieve the same object, a signal reproducing apparatus according to a fourteenth aspect of the present invention is the signal reproducing apparatus according to any one of the eighth to eleventh aspects, wherein the predetermined signal is included in the information signal. The signal is not frequency-modulated.

In order to achieve the same object, a signal reproducing apparatus according to a fifteenth aspect of the present invention is the signal reproducing apparatus according to any one of the eighth to eleventh aspects, wherein the predetermined signal is a tracking control pilot signal. Is characterized in that.

To achieve the same object, a signal reproducing apparatus according to a sixteenth aspect of the present invention is characterized in that the video signal and the audio signal are frequency-modulated into different frequency bands, respectively, and the frequency-modulated video signal and audio signal are then modulated. From the recording medium in which the information signal generated by frequency-multiplexing the tracking control pilot signal is recorded by the rotary head,
A signal reproducing apparatus comprising reproducing means for reproducing the recorded information signal by a rotary head, wherein a signal in a frequency band in which the frequency-modulated video signal exists is separated from the information signal reproduced by the reproducing means. Video signal separating means, a video signal demodulating means for demodulating the signal separated by the video signal separating means, and a predetermined signal separating means for separating a predetermined signal from the video signal demodulated by the video signal demodulating means, And a control unit configured to generate a control signal from the predetermined signal separated by the predetermined signal separation unit and control the rotating operation of the rotary head using the generated control signal.

In order to achieve the same object, the signal reproducing apparatus according to a seventeenth aspect of the present invention is the signal reproducing apparatus according to the sixteenth aspect, wherein the frequency modulated audio signal is present from the information signal reproduced by the reproducing means. And an audio signal demodulating means for demodulating the signal separated by the audio signal separating means.

In order to achieve the same object, a signal reproducing apparatus according to an eighteenth aspect of the present invention is the signal reproducing apparatus according to the sixteenth aspect or the seventeenth aspect, wherein the control means has a predetermined signal separated by the predetermined signal separating means. Feedback control means for feedback-controlling the rotating operation of the rotary head so that the relative speed between the recording medium and the rotary head becomes substantially constant by using a control signal generated from.

In order to achieve the same object, a signal reproducing apparatus according to a nineteenth aspect of the present invention is the signal reproducing apparatus according to the sixteenth aspect or the seventeenth aspect, wherein the control means has a predetermined signal separated by the predetermined signal separating means. Feedback control means for feedback-controlling the rotating operation of the rotary head so as to reduce the change in the relative speed between the recording medium and the rotary head, using a control signal generated from.

In order to achieve the same object, a signal reproducing apparatus according to a twentieth aspect of the present invention is the signal reproducing apparatus according to any one of the sixteenth to nineteenth aspects, wherein the predetermined signal is a vertical synchronizing signal. It is characterized by

In order to achieve the same object, a signal reproducing apparatus according to a twenty-first aspect of the present invention is the signal reproducing apparatus according to any one of the sixteenth to nineteenth aspects, wherein the predetermined signal is a horizontal synchronizing signal. It is characterized by

In order to achieve the same object, a signal reproducing apparatus according to a twenty-second aspect of the present invention is the signal reproducing apparatus according to any one of the sixteenth to nineteenth aspects, wherein the predetermined signal is included in the information signal. The signal is not frequency-modulated.

In order to achieve the same object, a signal reproducing apparatus according to a twenty-third aspect of the present invention is the signal reproducing apparatus according to any one of the sixteenth to nineteenth aspects, wherein the predetermined signal is a tracking control pilot signal. Is characterized in that.

[0040]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 1 is a block diagram showing a configuration of a signal reproducing apparatus according to a first embodiment of the present invention. This device is different from the above-described conventional signal reproducing device in that a reproduction reference signal extracting circuit 15, a detecting circuit 16 and a correcting circuit 17 are added. Therefore, in this device, the signal reproduction method is different from the conventional signal reproduction device,
The signal recording method is exactly the same. In FIG. 1,
The same components as those in FIG. 4 are designated by the same reference numerals.

In the figure, 1 is an audio input terminal and 2 is a video input terminal. The audio input terminal 1 is connected to the first frequency modulator 3, the video input terminal 2 is connected to the second frequency modulator 4, and the first frequency modulator 3 and the second frequency modulator 4 are connected. The recording amplifier 5 is connected to the output side. A rotary head 8 is connected to the output side of the recording amplifier 5, and the rotary head 8 is in contact with a recording tape 9 when recording / reproducing a signal.

On the other hand, a reference signal extracting circuit 6 is also connected to the video input terminal 2. Switch part is the recording side terminal 1
9, a reproducing side terminal 20 and a switch 21. The recording side terminal 19 is connected to the output side of the reference signal extracting circuit 6, and the reproducing side terminal 20 is connected to the output side of a reference signal generator 18 provided near the rotary head 8. Further, the switch 21 is connected to the input side of the rotation control circuit 7. When recording a signal, the switch 21 is connected to the recording-side terminal 19
On the other hand, the switch 21 contacts the reproducing side terminal 20 during signal reproduction.

A reproduction amplifier 10 is connected to the side from which the signal picked up by the rotary head 8 and the recording tape 9 is output, and the output side of the reproduction amplifier 10 is connected to the first demodulation circuit 11 and the second demodulation circuit 12. It is connected. A video output terminal 14 is connected to the output side of the second demodulation circuit 12.

To the output line of the reproduction amplifier 10, not only the first demodulation circuit 11 and the second demodulation circuit 12 but also the reproduction reference signal extracting circuit 15 is connected, and the reproduction reference signal extracting circuit 15 is connected.
The detection circuit 16 is connected to the output side of, and the correction circuit 17 is connected to the output side of the detection circuit 16. The output line of the first demodulation circuit 11 is connected to the correction circuit 17 instead of the audio output terminal 13, and the output line of the correction circuit 17 is connected to the audio output terminal 13. In addition,
The connection relationship of the second demodulation circuit 12 is similar to that of the conventional device.

When recording a signal, the audio input terminal 1
The audio signal input from the first frequency modulator 3 is frequency-modulated by the first frequency modulator 3, and the video signal input from the video input terminal 2 is frequency-modulated by the second frequency modulator 4, and these signals are recorded together. It is input to the amplifier 5.

The video signal input from the video input terminal 2 is also input to the reference signal extracting circuit 6. At the time of recording a signal, the switch 21 contacts the recording side terminal 19, so that the reference signal extracting circuit 6 is connected to the rotation control circuit 7. In the reference signal extracting circuit 6, the reference signal is extracted from the input video signal, and the reference signal is the rotation control circuit 7
Is input to The rotation control circuit 7 controls the rotation of the rotary head 8 based on the input reference signal so as to be synchronized with the video signal output from the recording amplifier 5, and the rotary head 8 controls the rotation to rotate the recording amplifier 5. The audio signal and the video signal output from are recorded on the recording tape 9. In the case of the rotary head recording system, since one field of a video signal is recorded on one track in most cases, a vertical synchronizing signal is often used as this reference signal. When the audio signal and the video signal are recorded on the recording tape 9, a tracking control pilot signal is recorded as an information signal in which these signals are frequency-multiplexed.

On the other hand, when the signal is reproduced, the switch 21 is in contact with the reproduction side terminal 20, so that the reference indicating the position of the rotary head 8 generated by the reference signal generator 18 provided close to the rotary head 8. Signal is rotation control circuit 7
Will be returned to This reference signal is a signal serving as a reference for rotation of the rotary head 8 in the video signal. Then, the rotation control circuit 7 controls the rotary head 8 based on the fed back reference signal so that the rotary head 8 maintains a constant rotation.

The signal picked up from the recording tape 9 by the rotary head 8 tracing the recording tape 9 is input to the reproduction amplifier 10 and amplified, and the audio signal is input to the first demodulation circuit 11. The video signal is input to the second demodulation circuit 12.

The reproduction reference signal extracting circuit 15 extracts the reproduction reference signal from the information signal which is the signal input from the reproduction amplifier 10. Here, the reproduction reference signal is a signal that is not modulated (frequency does not change) at the time of recording, and for example, a horizontal synchronizing signal or the like is adopted in the modulated wave in the video signal. The horizontal synchronizing signal is a constant signal that is irrelevant to the signal relating to the pattern of the input video signal,
Since the frequency remains constant even after frequency modulation, it is suitable as a reference signal. In detecting the change in the relative speed between the rotary head and the recording tape, for example, the change in the relative speed, that is, the jitter can be detected by performing the frequency / voltage conversion of the horizontal synchronizing signal. At that time, the voltage is set to increase as the frequency of the horizontal synchronizing signal increases. By observing the frequency fluctuation of this reference signal, the change in the relative speed between the rotary head 8 and the recording tape 9, that is, the jitter can be detected.

The reproduction reference signal extracted by the reproduction reference signal extraction circuit 15 is input to the detection circuit 16 and the detection circuit 1
6 generates a voltage signal according to the change in the relative speed between the rotary head 8 and the recording tape 9 based on this signal, and outputs the signal to the correction circuit 17. This voltage signal is representative of jitter.

The audio signal input from the reproduction amplifier 10 to the first demodulation circuit 11 is demodulated by the first demodulation circuit 11 to be returned to the original audio signal, and then the correction circuit 1
7 is input. This signal is a signal that is still affected by the jitter. On the other hand, the video signal input from the reproduction amplifier 10 to the second demodulation circuit 12 is demodulated,
It is immediately output via the video output terminal 14.

In the correction circuit 17, the audio signal input from the first demodulation circuit 11 is corrected by the voltage signal input from the detection circuit 16.

For example, if the demodulated signal of the audio signal has its output amplitude oscillating in the positive direction as the relative speed between the rotary head 8 and the recording tape 9 increases, the voltage signal from the detection circuit 16 is corrected at the correction stage. The magnitude and phase of the amplitude are adjusted so as to match the demodulated audio signal and then subtracted from the demodulated audio signal, resulting in the output from the first demodulation circuit 11 resulting from the change in relative speed. Can be canceled and the influence of jitter can be reduced. That is, the waveform of the voltage signal is converted so that the gain and phase match the waveform of the audio signal, and the waveform of the voltage signal is subtracted from the waveform of the audio signal, that is, corrected so as to be canceled. . As a result, a signal in which the influence of jitter is removed from the audio signal can be obtained. Then, the obtained audio signal is output via the audio output terminal 13.

With the signal reproducing apparatus according to the first embodiment, the reproduced signal of the voice containing the jitter is corrected in the direction in which the influence of the jitter is reduced at the signal output stage. Can be reduced.

(Second Embodiment) FIG. 2 is a block diagram showing the configuration of a signal reproducing apparatus according to the second embodiment of the present invention. This apparatus is different from the above-described conventional signal reproducing apparatus in that a reproduction reference signal extracting circuit 115, a detecting circuit 116 and a reference signal generating circuit 117 are added and a reference signal generator 18 is deleted. Therefore, in this apparatus, the signal reproducing method is different from the conventional signal reproducing apparatus, but the signal recording method is exactly the same. In FIG. 2, the same components as those in FIG. 4 are designated by the same reference numerals, and the description thereof will be omitted as appropriate.

To the output line of the reproduction amplifier 10, not only the first demodulation circuit 11 and the second demodulation circuit 12 but also the reproduction reference signal extracting circuit 115 is connected, and the output side of the reproduction reference signal extracting circuit 115 is detected. The circuit 116 is connected. A reference signal generation circuit 117 is connected to the output side of the detection circuit 116, and an output side of the reference signal generation circuit 117 is connected to the reproduction side terminal 20.

In the present apparatus, when the signal is reproduced, the recording tape 9 is recorded by the rotary head 8 until the signal is recorded.
The operation until the signal picked up from is input to the reproduction amplifier 10 is similar to that of the signal reproduction device according to the first embodiment.

The reproduction reference signal is extracted from the information signal, which is the signal input from the reproduction amplifier 10 to the reproduction reference signal extraction circuit 115, by the same processing as the processing by the reproduction reference signal extraction circuit 15 in the first embodiment. And is input to the detection circuit 116. The detection circuit 116 generates a voltage signal according to the change in the relative speed between the rotary head 8 and the recording tape 9 based on the reproduction reference signal. Here, when a signal that should originally be reproduced at a constant frequency is subject to fluctuations in frequency due to jitter, by configuring the circuit so that the voltage changes with respect to the changed frequency, the output voltage signal is It becomes a signal showing the fluctuation of the frequency and becomes the jitter itself.

The detection signal relating to the jitter detected in this way is output from the detection circuit 116 to the reference signal generation circuit 117.
To the reproduction side terminal 2 after being converted into a format suitable for rotation control of the rotary head 8 by the reference signal generation circuit 117.
It is input to the rotation control circuit 7 via 0 and the switch 21. The rotation control circuit 7 controls the rotation of the rotary head 8 according to the input signal.

Specifically, since the detection signal of the detection circuit 116 is a signal indicating the deviation of the relative speed between the rotary head 8 and the recording tape 9, the rotation control circuit 7 keeps this signal constant. That is, the relative speed is controlled to be constant. For example, the reference signal generating circuit 117 generates a reference signal for controlling the rotation of the rotary head 8 so that the jitter is canceled, and the rotary head 8 is rotationally controlled according to the reference signal.

The connection relation and operation of the reproduction amplifier 10 and the first demodulation circuit 11 are similar to those of the conventional device.

As described above, since the output signal of the reproduction amplifier 10 is always fed back to the rotation control circuit 7, the audio signal output from the reproduction amplifier 10 to the first demodulation circuit 11 and the second demodulation circuit 12 and The video signal has reduced jitter itself.

Conventionally, since the rotation is controlled based on the signal indicating the reference position of the rotary head 8, if the rotation of the rotary head 8 is uneven or the recording tape 9 is expanded or contracted, it is not possible to keep the relative speed constant. However, according to the signal reproducing apparatus according to the second embodiment, the rotation of the rotary head 8 is feedback-controlled so that the jitter itself is reduced from the output signal of the reproduction amplifier 10. It is possible to suppress the occurrence of jitter at the stage of tracing the recording tape 9 by 8. As a result, not only the distortion and noise of the reproduced sound due to the jitter can be reduced, but also the image quality of the reproduced image can be improved.

(Third Embodiment) FIG. 3 is a block diagram showing the structure of a signal reproducing apparatus according to the third embodiment of the present invention. This device is different from the above-described conventional signal reproducing device in that a reproduction reference signal extracting circuit 215, a detecting circuit 216 and a reference signal generating circuit 217 are added, and a reference signal generator 18 is deleted. Therefore, in this apparatus, the signal reproducing method is different from the conventional signal reproducing apparatus, but the signal recording method is exactly the same. Note that, in FIG. 3, the same components as those in FIG. 4 are designated by the same reference numerals, and the description thereof will be appropriately omitted. In this device, the connection position on the input side of the reproduction reference signal extracting circuit 215 is set to the second demodulation circuit 12
The output side is different from the signal reproducing apparatus according to the second embodiment in which the first demodulation circuit 11 and the second demodulation circuit 12 are input sides.

On the output side of the second demodulation circuit 12, not only the video output terminal 14 but also the reproduction reference signal extracting circuit 215 is connected, and the output side of the reproduction reference signal extracting circuit 215 is connected to the detection circuit 216. . The reference signal generation circuit 217 is connected to the output side of the detection circuit 216, and the reproduction side terminal 20 is connected to the output side of the reference signal generation circuit 217.

In the present apparatus, during reproduction of a signal, the recording tape 9 is recorded by the rotary head 8 until the signal is recorded.
The operation until the signal picked up from is input to the first demodulation circuit 11 and the second demodulation circuit 12 is
It is similar to the signal reproducing apparatus according to the embodiment.

The video signal demodulated by the second demodulation circuit 12 is input to the reproduction reference signal extracting circuit 215, and in the reproduction reference signal extracting circuit 215, a signal which should have a constant period at the time of signal recording from this video signal (for example, The vertical synchronizing signal) is extracted as the reproduction reference signal. The cycle of the reproduction reference signal varies if there is jitter.

From the reproduction reference signal extracting circuit 215, the extracted reproduction reference signal is input to the detecting circuit 216. The detection circuit 216 is configured so that the output voltage changes in proportion to the cycle of the input reproduction reference signal, and generates a voltage signal indicating the cycle fluctuation caused by jitter.

The voltage signal generated from the detection circuit 216,
That is, the detection signal is input to the reference signal generation circuit 217, converted into a format suitable for rotation control of the rotary head 8 by the reference signal generation circuit 217, and then the rotation control circuit 7 via the reproduction side terminal 20 and the switch 21. Entered in. The rotation control circuit 7 controls the rotation of the rotary head 8 according to the input signal.

Here, the detection signal of the detection circuit 216 is output as a constant voltage if there is no jitter, so the actual output voltage from the detection circuit 216 and the output voltage when there is no jitter. By taking the difference between and, it is possible to obtain a detection signal in which the reference is set so that the detection signal when there is no jitter is constant at zero. Therefore,
When the reference is set in this way, the reference signal generation circuit 217 generates a reference signal for controlling the rotation of the rotary head 8 so that the detection signal of the detection circuit 216 decreases with zero as a target. To do. Thereby,
The rotation of the rotary head 8 is feedback-controlled, and the relative speed between the rotary head 8 and the recording tape 9 is controlled to be constant.

According to the signal reproducing apparatus of the third embodiment, the same effect as that of the second embodiment can be obtained.
Furthermore, since the sampling position of the reproduction reference signal is after the demodulation of the video signal, the structure for frequency / voltage conversion can be simplified.

In the first, second, and third embodiments, the reproduction reference signal may be a signal other than those exemplified as long as it is a signal that is not modulated at the time of signal recording. For example, vertical synchronization of a video signal. It may be a signal or a horizontal synchronizing signal, or a pilot signal for tracking.

[0074]

As described above, according to the first aspect of the present invention.
According to the signal reproducing apparatus of the present invention, the predetermined signal is separated from the reproduced information signal, the signal of the frequency band in which the frequency-modulated audio signal exists is separated from the reproduced information signal, and the separated signal is separated. A signal is demodulated, a correction signal is generated from the separated predetermined signal, and the demodulated signal is corrected using the generated correction signal,
For example, the influence of jitter caused by the change in the relative speed between the recording medium and the rotary head during recording or reproduction, or the influence of jitter caused by the expansion or contraction of the recording medium,
Can be reliably removed with a simple configuration. Therefore, it is possible to reduce the distortion and noise of the reproduced sound due to the jitter.

According to the signal reproducing apparatus of the third aspect of the present invention, the recorded information signal is reproduced from the recording medium, the audio signal is detected from the reproduced information signal, and the separated predetermined signal is detected. Since the change signal indicating the change in the relative speed between the recording medium and the rotary head is detected from the signal and the detected change signal is subtracted from the detected voice signal, the influence of jitter can be more accurately detected. Can be removed.

According to the signal reproducing apparatus of the eighth aspect of the present invention, a predetermined signal is separated from the reproduced information signal,
A control signal is generated from the separated predetermined signal, and the rotation operation of the rotary head is controlled by using the generated control signal, so that the influence of jitter can be reliably removed with a simple configuration, and It is possible to reduce distortion and noise in the reproduced sound and reproduced image due to the noise.

According to the signal reproducing apparatus of the tenth or eighteenth aspect of the present invention, the rotational operation of the rotary head is feedback-controlled so that the relative speed between the recording medium and the rotary head becomes substantially constant.

According to the signal reproducing apparatus of the eleventh or nineteenth aspect of the present invention, the rotational operation of the rotary head is feedback-controlled so as to reduce the change in the relative speed between the recording medium and the rotary head.

According to the sixteenth aspect of the signal reproducing apparatus of the present invention, the signal in the frequency band in which the frequency-modulated video signal exists is separated from the reproduced information signal, and the separated signal is demodulated. , A predetermined signal is separated from the demodulated video signal, a control signal is generated from the separated predetermined signal, and the rotation operation of the rotary head is controlled using the generated control signal. The influence of jitter can be reliably removed with a simple configuration, and the distortion and noise in the reproduced sound and reproduced image due to the jitter can be reduced.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a signal reproducing device according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a signal reproducing device according to a second embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a signal reproducing device according to a third embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of a conventional signal reproducing device.

[Explanation of symbols]

 7 Rotation Control Circuit 8 Rotating Head 9 Recording Tape 11 First Demodulation Circuit 12 Second Demodulation Circuit 15 Reproduction Reference Signal Extraction Circuit 115 Reproduction Reference Signal Extraction Circuit 215 Reproduction Reference Signal Extraction Circuit 16 Detection Circuit 116 Detection Circuit 216 Detection Circuit 117 Reference signal generation circuit 217 Reference signal generation circuit 17 Correction circuit

Claims (23)

[Claims] 1. An information signal generated by frequency-modulating a video signal and an audio signal into different frequency bands, and then frequency-multiplexing a tracking control pilot signal to the frequency-modulated video signal and audio signal. A signal reproducing device comprising a reproducing means for reproducing the recorded information signal from a recording medium on which is recorded, a predetermined signal separating means for separating a predetermined signal from the information signal reproduced by the reproducing means, An audio signal separation means for separating a signal in a frequency band in which the frequency-modulated audio signal exists from the information signal reproduced by the reproduction means, and an audio signal demodulation for demodulating the signal separated by the audio signal separation means Means for generating a correction signal from the predetermined signal separated by the predetermined signal separating means, and generating the correction signal by the correction signal. Signal reproducing apparatus characterized by comprising a correction means for correcting the signal demodulated by the audio signal demodulating means are. 2. A video signal separating means for separating a signal in a frequency band in which the frequency-modulated video signal exists from the information signal reproduced by the reproducing means, and a signal demodulated by the video signal separating means. The signal reproducing apparatus according to claim 1, further comprising: 3. The reproducing means includes a rotary head for reproducing the recorded information signal from the recording medium, and an audio signal detecting means for detecting an audio signal from the information signal reproduced by the rotating head. The correction means includes a change signal detection means for detecting a change signal indicating a change in relative speed between the recording medium and the rotary head from the predetermined signal separated by the predetermined signal separation means, and the change signal detection means. 3. The signal reproducing apparatus according to claim 1 or 2, further comprising: subtraction means for subtracting the detected change signal from the audio signal detected by the audio signal detection means. 4. The signal reproducing device according to claim 1, wherein the predetermined signal is a vertical synchronizing signal. 5. The signal reproducing apparatus according to claim 1, wherein the predetermined signal is a horizontal synchronizing signal. 6. The signal reproducing apparatus according to claim 1, wherein the predetermined signal is a signal that is not frequency-modulated in the information signal. 7. The signal reproducing apparatus according to claim 1, wherein the predetermined signal is a tracking control pilot signal. 8. An information signal generated by frequency-modulating a video signal and an audio signal into different frequency bands, and then frequency-multiplexing a tracking control pilot signal to the frequency-modulated video signal and audio signal. Is a signal reproducing device having a reproducing means for reproducing the recorded information signal from the recording medium recorded by the rotating head by the rotating head, the signal reproducing device separating the signal from the information signal reproduced by the reproducing means. And a control means for generating a control signal from the predetermined signal separated by the predetermined signal separation means, and controlling the rotating operation of the rotary head using the generated control signal. Characteristic signal reproducing device. 9. An audio signal separating means for separating a signal in a frequency band in which the frequency-modulated audio signal exists from the information signal reproduced by the reproducing means, and a signal demodulated by the audio signal separating means. Audio signal demodulating means, video signal separating means for separating a signal in a frequency band in which the frequency-modulated video signal exists from the information signal reproduced by the reproducing means, and a signal separated by the video signal separating means 9. The signal reproducing apparatus according to claim 8, further comprising a video signal demodulating means for demodulating the video signal. 10. The control means uses a control signal generated from a predetermined signal separated by the predetermined signal separation means so that the relative speed between the recording medium and the rotary head becomes substantially constant. 10. The signal reproducing apparatus according to claim 8, further comprising feedback control means for feedback-controlling the rotating operation of the rotary head. 11. The control means reduces a change in relative speed between the recording medium and the rotary head by using a control signal generated from a predetermined signal separated by the predetermined signal separation means. 10. The signal reproducing apparatus according to claim 8, further comprising feedback control means for feedback-controlling the rotating operation of the rotary head. 12. The signal reproducing device according to claim 8, wherein the predetermined signal is a vertical synchronizing signal. 13. The signal reproducing apparatus according to claim 8, wherein the predetermined signal is a horizontal synchronizing signal. 14. The signal reproducing apparatus according to claim 8, wherein the predetermined signal is a signal that is not frequency-modulated in the information signal. 15. The tracking control pilot signal, wherein the predetermined signal is a tracking control pilot signal.
1. The signal reproducing device according to any one of 1. 16. An information signal generated by frequency-modulating a video signal and an audio signal into different frequency bands, and then frequency-multiplexing a tracking control pilot signal to the frequency-modulated video signal and audio signal. Is a signal reproducing apparatus having reproducing means for reproducing the recorded information signal from the recording medium recorded by the rotating head by the rotating head, wherein the frequency modulation is performed from the information signal reproduced by the reproducing means. Video signal separating means for separating a signal in the frequency band in which the video signal exists, video signal demodulating means for demodulating the signal separated by the video signal separating means, and a predetermined signal from the video signal demodulated by the video signal demodulating means Signal separating means for separating the signals of the above, and the predetermined signal separated by the predetermined signal separating means It generates et control signal, the signal reproducing apparatus characterized by comprising a control means for controlling the rotation of the rotary head by using a control signal which is the product. 17. An audio signal separation means for separating a signal in a frequency band in which the frequency-modulated audio signal exists from the information signal reproduced by the reproduction means, and a signal demodulated by the audio signal separation means. 17. The signal reproducing apparatus according to claim 16, further comprising: an audio signal demodulating unit that operates. 18. The control means uses a control signal generated from a predetermined signal separated by the predetermined signal separation means so that the relative speed between the recording medium and the rotary head becomes substantially constant. 18. The signal reproducing apparatus according to claim 16 or 17, further comprising feedback control means for feedback-controlling the rotating operation of the rotary head. 19. The control means reduces a change in relative speed between the recording medium and the rotary head by using a control signal generated from a predetermined signal separated by the predetermined signal separation means. 18. The signal reproducing apparatus according to claim 16 or 17, further comprising feedback control means for feedback-controlling the rotating operation of the rotary head. 20. The signal reproducing apparatus according to claim 16, wherein the predetermined signal is a vertical synchronizing signal. 21. The signal reproducing apparatus according to claim 16, wherein the predetermined signal is a horizontal synchronizing signal. 22. The signal reproducing apparatus according to claim 16, wherein the predetermined signal is a signal that is not frequency-modulated in the information signal. 23. The predetermined signal is a tracking control pilot signal.
20. The signal reproducing device according to any one of 19.