KR850001007B1 - Video signal recorder - Google Patents

Abstract

A VTR uses a signal superimposed on the audio signal track of a tape. The signals used may be of 15-21HZ frequency and 10-30dB below the audio signal level. A decision signal-generating circuit responds to the reproduced signals to produce control signals dependent on the audio mode currently employed. These signals may be fed to a known type of decoder used to retrieve separate audio channels from a multiplexed audio signal. Information to an operator may be provided by a display driven from the control signal to the audio mode in use. Pref. an encoder is included for multiplexing, in response to the decision signal and the reproduced audio, to produce an audio signal in the stereo, mono, or bilingual modes.

Description

Video signal recording / playback device

1 is a block diagram showing an embodiment of the present invention.

2 is a diagram showing an example of a recording configuration of a video tape.

3 is a circuit diagram showing an example of a determination circuit included in the first embodiment.

4 is a graph for explaining the operation of the third embodiment.

5 is a waveform diagram for explaining the operation of the embodiment shown in FIG.

6 is a circuit diagram showing another embodiment of the determination circuit used in the first embodiment.

7 is a block diagram showing another embodiment of the present invention, in which the determination signal generation circuit is mainly changed as compared with the first embodiment.

FIG. 8 is a circuit diagram showing an example of a determination circuit used in the FIG. 7 embodiment.

9 is a waveform diagram for explaining the operation of the embodiment shown in FIG. 7 and FIG.

FIG. 10 is a circuit diagram showing another example of the determination circuit used in the FIG. 7 embodiment. FIG.

FIG. 11 is a waveform diagram for explaining the operation of the FIG.

12 is a block diagram showing another embodiment of the present invention.

13 (a) and 13 (b) are waveform diagrams for explaining the operation of the twelfth embodiment.

FIG. 14 is a circuit diagram showing an example of an identification signal generating circuit used in the FIG. 12 embodiment.

FIG. 15 is a block diagram showing an example of a determination signal generating circuit used in the FIG. 12 embodiment.

FIG. 16 is a circuit diagram showing an example of a determination circuit used in the FIG. 15 embodiment.

17 and 18 are waveform diagrams for explaining the operation of the FIG. 16 embodiment, respectively.

19 is a block diagram showing another embodiment of the present invention.

20 is a block diagram showing the main parts of the FIG. 19 embodiment.

21 is a timing chart for explaining the operation of the FIG. 19 embodiment in comparison with the FIG. 12 embodiment.

FIG. 22 is a block diagram showing a determination signal generating circuit of the FIG. 19 embodiment.

FIG. 23 is a waveform diagram for explaining the operation of the circuit of FIG.

* Explanation of symbols for main parts of the drawings

(9) (11): Video Head (10): Video Tape

(2) (14): Video tracks (24) (34): Voice tracks

(23) (33): Voice head (7) (21) (32) (147) (153): Switch

(35) (35 ') (35 "): Identification signal preparation circuit (27): Mixer

(57): Video signal reproducing processing unit (65): Encoder

(67): Equalizer (73) (73 ') (73 "): Decision signal generating circuit

(59): RF modulator (39) (41): Divider

(81) (83): Decision circuit (77) (79) (161) (166): Band filter

(101): control head (103): waveform shaping circuit

(107): first integrating circuit (109): second integrating circuit

(111) (111 '): switching transistor 115: comparator

(107 '): Low Pass Filter (129): Multiplier

(135): gate circuit (131): high pass filter

(133): rectifier circuit (151): inverter

(169): multiplication circuit (171): judgment circuit

(167): phase adjusting circuit (168): π / 2 phase circuit

The present invention relates to a video signal recording / reproducing apparatus. More particularly, the present invention relates to an example in which an audio signal to be multiplexed together with a video signal is recorded on a recording medium having a separately formed voice track and a video track. A video signal recording / reproducing apparatus such as a tape recorder.

Conventionally, in the VTR, it has already been proposed that the multiplexed audio signal included in the television signal can be recorded on the audio track of the video tape and reproduced therein. In this proposed VTR, the multiplexed audio signal included in the transmitted television signal is given to the decoder, and the audio signals of two channels are output from the decoder and they are recorded in two separate audio tracks. The audio signals of the two channels are left and right signals, main and sub signals, or the same monaural signal, which are different depending on the stereo method, the Bailingal method, or the monaural method. However, this type of conventional VTR has a function of identifying the type of audio signal (stereo, bialing or monaural) recorded on the voice track and encoding the reproduced voice signal into a multiplexed voice signal for a television receiver. It does not have a function to). For this reason, the two-channel audio signal reproduced on the video tape is used as an aspect in which the speaker included in the television receiver is driven directly without being provided to the television receiver from the antenna input, i.e. without intervening a special signal conversion circuit. It is just being. In this way, when the speaker of the television receiver is directly driven in the VTR, there is no need to pass the encoder on the VTR side and the signal conversion circuit on the television receiver side, thereby reducing the chance of deterioration of the sound signal and the cash VTR. It is not necessarily advantageous in view of the general connection mode with the television receiver. That is, since the VTR and the television receiver are generally connected through the antenna terminal, the audio signal is not transmitted through the antenna terminal for the television receiver which does not have an input terminal for such an audio signal. It means that it can not be transmitted. Although it has audio signal input terminal, video signal input terminal for 2 video signals, 2 audio signal input terminal and signal line connected to each input terminal must be installed. When using VTR, Connection becomes crowded.

In addition, the multiplexed audio signal included in the television signal transmitted from the broadcasting station is formed as a mixed signal including an audio signal and an identification signal for identifying the type of the audio signal. For example, in stereo mode, one channel of the audio signal includes an (L + R) signal, and the other channel includes an FM modulated (L-R) signal and again an AM modulated stereo signal. This identification signal generally has a high frequency, for example 55.125 KHz (3.5 times the horizontal frequency) and cannot be recorded on videotape in the current standardized recording configuration. In other words, in the current standardized recording configuration, video tracks and voice tracks are formed separately, and video tracks are recorded in the form of a helical scan, so that video signals of a wide band can be recorded as they are. Is not allowed. Therefore, if the identification signal is recorded on the video tape, there is no other way but to record on the voice track. However, as mentioned above, the identification signal cannot be recorded on the voice track as a high frequency signal. Is very slow, for example 1.3 cm / sec, so the upper limit of the recordable signal frequency is about 10 KHz. Therefore, in all currently known VTRs, when a television signal is input to a television receiver, a separate manual switch is installed to identify whether the recorded audio signal is a stereo, a baling or monaural method. there was. There is another drawback of poor operability in the conventional VTR which passively identifies such a kind of voice signal.

Therefore, the main object of the present invention is an improved video signal recording / reproducing, which makes it possible to automatically identify the type by recording and reproducing a signal for identifying the type or method of the multiplexed voice signal on the voice track of the recording medium. To provide a device.

The video signal recording / reproducing apparatus according to the present invention includes a recording medium having a separately formed voice track and a video track, wherein the voice track is superimposed on an audio signal and an identification signal for identifying the type of the audio signal is superimposed. Is recorded. Such identification signals are recorded on voice tracks and are also selected for reproducible frequencies from there, eg 10 KHz or less, preferably at very low frequencies such as 15 to 20 Hz and also at relatively low levels, eg 10 KHz or less. For example, very low frequencies, such as 15 to 20 Hz, are also recorded at relatively low levels, for example 10 to 30 dB lower than for voice signals. In accordance with the identification signal reproduced from the audio track, a determination signal indicating the type of the recorded audio signal, for example, the stereo system, the Baying galle system or the monaural system, is obtained.

In a preferred embodiment of the present invention, means for producing a multiplexed audio signal for giving to a television receiver in accordance with the audio signal reproduced in the audio track and the determination signal obtained as described above, for example, an encoder are provided. The multiplexed audio signal from this encoder is added to the RF modulator together with the video signal reproduced in the video track and subjected to appropriate processing. In the RF modulator, the input video signal and the multiplexed voice signal are the same as those transmitted from a normal broadcasting station, and are obtained as different RF television signals. Therefore, the outputs may be connected directly to the antenna terminals of the television receiver. In a television receiver, since a television signal having the same configuration as a regular radio wave propagation can be provided through an antenna terminal in a video signal recording / reproducing apparatus, it is not necessary to install an input terminal separately on the television receiver and to avoid a complicated connection line connection. have.

In another preferred embodiment, the identification signal to be recorded includes the type information in the frequency. In another embodiment, an identification signal with the same frequency and type information in phase is used.

Next, preferred embodiments of the present invention will be described with reference to the drawings.

1 is a block diagram showing an embodiment of the present invention. This embodiment describes an example in the case where the present invention is applied to a VTR similarly to each of the embodiments described later, but it is pointed out in advance that the present invention is not limited to the VTR.

A television signal from an antenna (not shown) is applied to the input terminal 1, and this television signal is input to the tuner 3. The tuner 3 outputs a standard television signal including a video signal and a multiplexed voice signal, and the video signal is provided to the video signal recording processing section 5. The video signal recording processing section 5 processes the video signal to be suitable for recording on the video tape (not shown) as is known, and the processed signal is transmitted through two video heads (switch 7). 9) and (11). The two video heads 9 and 11, as is known, form the video tracks 12 and 14 on the videotape 10, respectively, in a configuration as shown in FIG.

On the other hand, the television signal from the tuner 3 is provided to the decoder 13. The decoder 13 decodes the multiplexed audio signal included in the television signal into the audio signals C and D of the two channels, and at the same time, the stereo signal and the bi-galling method. Alternatively, signals A and B representing the monaural scheme are output. As the decoder 13, for example, an integrated circuit TA7633P manufactured by Tokyo Ohshi Bauradengi Co., Ltd. can be used. More specifically, the decoder 13 outputs the signals as shown in the following first table to the output terminals A, B, C and D, respectively, according to the type of the multiplexed audio signal. .

[Table 1]

In the first table, the L signal and the R signal represent the left signal and the right signal, respectively, the M signal and the S signal represent the main signal and the sub signal, respectively, and the M _o signal represents the same monaural signal.

In addition, one example of such a television audio multiplex is currently employed in Japan, and audio multiplex is also employed in West Germany.

Indicators 15 and 17, which are driven and displayed respectively in accordance with the high-level signals A and B from the decoder 13, are installed. In the case of the stereo system, the indicator 15 is mounted. In the case of the Bailinggal method, the indicators 17 are driven to display, respectively. In the monaural mode, the two indicators 15 and 17 are not driven to display together. From the states of the indicators 15 and 17, it is possible to know how the operator is currently recording. In addition, the audio signal of one channel from the decoder 13 is provided to the audio signal recording processing unit 19, and as is known, the signal processing is performed to fit the recording therein, and the processed signal is transmitted via the switch 21. The voice head 23 is attached. In addition, the audio signal of the other channel from the decoder 13 is provided to the audio signal recording processing unit 29 through the high pass filter 25 and the mixer 27, and signal processed therein to be suitable for recording and processing thereof. The signal is provided to the other voice head 33 via the switch 31. The two voice heads 23 and 33 form the first and second voice tracks 24 and 34, respectively, as shown in FIG. In addition, the high pass filter 25 has a cutoff frequency of 50 Hz and a component below 50 Hz of the audio signal of the other channel is attenuated therein, and the identification signal I1 or I2 described later in the band. In this way, the mixer 27 superimposes the identification signal I1 or I2 provided from the switch circuit 51 to be described later in the band where the audio signal is attenuated. In addition to the audio signal of the other channel described above, an additional identification signal may be provided in 29. Therefore, the voice track 34 (FIG. 2) formed by the voice head 33 is provided in addition to the audio signal. An identification signal may be included.

The identification signal generating circuit 35 receives a reference signal having, for example, a frequency of 30 Hz (in the case of the NTSC system) at its input terminal 37. As described later, the reference signal is a control signal applied to the vertical synchronization signal Vsync or the capstan servo circuit 105 (to be described later) included in the television signal. The 30 Hz reference signal applied to the input terminal 37 is provided to the divider 39 and 41 each having a different division ratio. The divider 39 divides the applied reference signal into 1/2 to output a signal of 15 Hz, and the divider 41 outputs a signal of 20 Hz with a division ratio of 2/3. The 15 Hz signal from the divider 39 is supplied to the switch circuit 51 as the first identification signal I1 through the band filter 43 and the output terminal 47. Similarly, the 20 Hz signal from the divider 41 is provided to the switch circuit 51 as the second identification signal I2 through the band pass filter 45 and the output terminal 49. In this manner, the identification signal generating circuit 51 outputs the identification signal I1 or I2 at least in the case of the recording method, in the method other than the monaural method. The switch circuit 51 includes switches 53 and 55 which receive two identification signals I1 and I1, respectively, and the outputs of these switches 53 and 5 are commonly supplied to the mixer 27. Is given. The switches 53 and 55 are closed by the high level signals A and B from the decoder 13, respectively.

That is, when the audio signal to be recorded is in the stereo system, the signal A from the decoder 13 becomes high level, the switch 53 included in the switch circuit 51 is closed and the mixer 27 is identified. The first identification signal I1 (15 Hz) from the output terminal 47 of the signal generating circuit 35 is applied. Therefore, in the stereo system, the first identification signal I1 is recorded together with the right R signal in the second audio track of [Tape 10 (FIG. 2). In addition, in the bailing gal system, the switch 55 of the switch circuit 51 is closed by the high-level signal B from the decoder 13, and the second signal is output from the output terminal 49 of the identification signal generation circuit 35. The identification signal I2 (20 Hz) of is given to the mixer 27 via this switch 55. Accordingly, the negative signal S2 and the second identification signal I2 are recorded in the second voice track 34 in the Baying-gal method. In the monaural mode, the signals A and B from the decoder 13 are together at a low level, and all of the switches 53 and 55 included in the switch circuit 51 are left open. No identification signal is given to (27). Therefore, in the monaural method, only the monaural (M _o ) signal is recorded in the second audio track 34. The mixer 23 also limits the level of the identification signal so that the head 33 can record each identification signal I1 or I2 at a level 10 to 30 dB lower than that of the audio signal. In this way, it is considered that the identification signal I1 or I2 does not interfere with the audio signal.

The vertical synchronization signal Vsync extracted from the television signal is waveform-shaped and outputs, for example, a square wave signal of 60 Hz. The square wave signal is given as a reference signal to the input terminal 37 of the identification signal generation circuit 35 described above via the 1/2 division circuit 98 and the selection circuit 95, and is also provided through the switch 99. To the control head 101. The control head 101 thus forms a control track 102 on the tape 10 (FIG. 2). The selection circuit 95 is for selectively giving the input terminal 37 the output of the waveform shaping circuit 97 or 103 in a recording manner and a reproduction manner.

Next, the reproduction system will be described. Since the reproduction system is regarded as an inverse conversion of the recording system, it is actually configured to use many mechanisms or circuits. However, it is noted that the reproduction system is shown separately from the recording system for convenience of description.

The switches 7, 21, 31 and 99 are switched from the contact R for the recording method to the contact P for the reproduction method by an operation switch not shown. When the switch 7 is switched to the reproduction method, the video signals reproduced by the video heads 9 and 11 in the video tracks 12 and 14 (FIG. 2) are given to the video signal reproduction processing unit 57. do. The video signal reproducing processor 57 reconstructs the reproduced video signal provided therein into a standard television signal format and gives it to an RF modulator 59 having a function substantially the same as that of a normal broadcasting station. When the switch 21 is switched to the reproduction method, the audio signal of the first channel reproduced in the first audio track 24 is derived by the first audio head 23, and the equalizer 61 and Through the amplifier 63, the voice multiplexing encoder 65 is provided. The voice signal reproduced by the second voice track 34 by the voice head 33 when the switch 31 is switched to the reproduction method. If necessary, an added identification signal is derived and applied to the encoder 65 via the equalizer 67, the high pass filter 69, and the amplifier 71. The high pass filter 69 blocks the low frequency component of the signal from the second audio track 34 reproduced by the head 3 with a cutoff frequency of approximately 50 hZ similar to the high pass filter 25 described above.

The reproduction signal from the equalizer 67 is supplied to the determination signal generation circuit 73 again. The determination signal generation circuit 73 is for outputting determination signals D ₁ and D ₂ indicating the type of multiplexing of the recorded and reproduced audio signal. The amplifier 75 included in the determination signal generating circuit 73 receives the reproduction signal from the equalizer 67 and the output of the amplifier 75 is applied to the band filters 77 and 79 having different pass bands, respectively. do. The band filter 77 extracts a 15 Hz signal from the reproduction signal, and the band filter 79 extracts a 20 HZ signal. The respective outputs of the bandpass filters 77 and 79 are input to the determination circuits 81 and 83, respectively. The determination circuits 81 and 83 have a circuit configuration as shown in FIG. 3 to be described later, and determine whether or not the level of the signal provided by the corresponding band filters 77 and 79 is above a predetermined level. When the 15 Hz signal, i.e., the first identification signal I1, is included in the reproduction signal, the determination circuit 81 outputs a high level determination signal D ₁ , and the signal D ₁ is output terminal 85. The encoder 65 is given to the encoder 65. The judging circuit 83 derives the high-level judging signal D ₂ when the 20 Hz signal, that is, the second identification signal I 2 is included in the reproduction signal, and the signal D ₂ is output terminal 87. Is given to the encoder 65 through. Further, the determination signal generation circuit 73 and the output terminals 85 and 87 are connected to the indicators 89 and 91, respectively, so that the indicator 89 is driven to display when the determination signal D ₁ is at the high level. The indicator 91 is driven to display when the determination signal D ₂ is at the high level. That is, when the reproduced multiplexed audio signal is in the stereo system, the determination signal generating circuit 73 obtains the high level determination signal D ₁ , and the display 89 is driven to display and display in the stereo system. In addition, the high level signal D ₂ is obtained from the output terminal 87, and the display 91 is driven to display that the multiplexed audio signal reproduced at that time has been recorded in the Baying galle method. In the monaural mode, the two determination signals (D ₁ ) and (D ₂ ) are together at the low level, and both of the indicators (89) and (91) are not driven to display together, so that the audio signal currently reproduced is monaural. What was recorded in the manner is displayed.

The voice multiplexing encoder 65 can use, for example, an integrated circuit LA7017 manufactured by Tokyo Ohsan Odengi Co., Ltd. This encoder 65 is broadcast in accordance with the audio signals of the first and second channels provided by the amplifiers 63 and 71 and the determination signal 73 or (D ₁ ) provided by the determination signal generation circuit. A multiplexed voice signal is formed in a stereo system, a bialing method, or a monaural system having the same format as that of radio waves, and is then given to the RF modulator 59. The RF modulator 59 is based on a sound signal composed of a playback video signal composed of a normal television video signal from the video signal reproduction processing unit 57 and a normal television multiplexed audio signal from the encoder 65, such as broadcast propagation. An RF signal is output, and this RF signal is applied to an antenna terminal of a television receiver (not shown) at the output terminal 60. In this way, the output signal from the VTR can be directly provided to the antenna terminal of the television receiver. For this reason, there is no need to attach a special connection terminal to the television receiver, and thus complicated wiring work is unnecessary.

In addition, when the switch 99 is switched to the reproducing method, a control signal of 60 Hz is recorded and displayed on the control track 102 of the tape (FIG. 2) by the control head 101, and the reproducing control signal is a waveform shaping circuit ( 103). The waveform shaping circuit 105 shapes a given reproduction control signal into a square wave, applies it to the capstan servo circuit 105, and simultaneously applies it to the above-described selection circuit 95. As is known, the capstan servo circuit 105 performs servo control to drive the tape so that the capstan motor of the VTR is synchronized with the rotation of the heads 9 and 11. In this way, in the reproduction method, the reproduction control signal 60Mh may be applied to the input terminal 37 of the identification signal generation circuit 35 in the selection circuit 95.

The decision circuit 81 included in the decision signal generation circuit 73 is shown in detail in FIG. The decision circuit 81 is a second integration circuit (109) having a time constant of a larger second (t ₂₎ relative to the integrating circuit 107 and a time constant (t ₁₎ of claim 1 with the number (t ₁₎ time constant It includes. The switching transistor 111 is inserted between the integrating circuits 107 and 109. From the input terminal 80, a signal of 15 hz from the bandpass filter 77 (FIG. 1) is applied to the first integrating circuit 107 via the diode 119, and the diode 117 is provided. Is provided to the second integrating circuit 109 via. The output of the first integrating circuit 107 is applied to the base of the switching transistor 111 so that the emitter collector of the switching transistor 111 is connected between the input of the second integrating circuit 109 and the ad potential. . The output of the second integrating circuit 109 is given the + input of a comparator 115 consisting of, for example, an operational amplifier. The reference voltage from the terminal 113 is applied to the-input of the comparator 115. The output 116 of the comparator 115 is connected to the output terminal 85. In addition, the description of the other occupancy circuit 83 as a configuration of the wagon octopus is omitted here.

The first integrating circuit 107 has a transfer characteristic as shown by the dotted line 121 in FIG. 4 and the second integrating circuit 109 has a transfer characteristic as shown by the dashed dashed line 123 in FIG. Therefore, the transmission characteristic leading to the + input of the comparator 115 becomes as shown by the solid line 125 of FIG. In other words, when the duration of the 15 Hz signal provided from the input terminal 80 is shorter than the time determined by the time constant t ₁ of the first integrating circuit 107, the signal is applied to the second integrating circuit 109. There is no work. That is, when the output of the first integrating circuit 107 is less than or equal to a predetermined value, the switching transistor 111 remains in a conducting state, and a signal of 15 Hz through the diode 117 flows into the ground potential through the switching transistor 111 and is formed. It is not given to the two integrating circuits 109. If the duration of the 15 Hz signal is long, the switching transistor 111 is cut off by the output of the integrating circuit 107 and the 15 Hz signal from the input terminal 80 is applied to the second integrating circuit 109.

Therefore, as shown in FIG. 5 (a), for example, as shown in FIG. 5 (a), when the 15Hn signal containing the noise component N, that is, the first identification signal 11, is applied to the + input of the comparator 115, As shown in FIG. 5 (b), a signal whose amplitude of noise component N is suppressed is provided. When the comparison level 127 of the comparator 115 is set to the reference voltage 113, the output terminal 116 of the comparator 115 has an accurate determination signal that is not affected by the noise component as shown in FIG. 5 (c). (D ₁ ) can be obtained. That is, the determination circuit 81 can derive the determination signal D ₁ which responds only to the components of the true or normal identification signal I ₁ .

Further, the second determination circuit 83 is similarly configured and derives the determination signal D _{2 in} response thereto only when the regular identification signal I2 is applied.

The determination circuit in which the malfunction due to the noise component is prevented is particularly effective when the tape on which the identification signal is recorded is reproduced without resorting to the method of the present invention. That is, when the recorded tape is reproduced without using the method of the present invention, a noise component as shown in FIG. 5 (a) may be provided to the determination circuit, but the determination circuit 81 does not respond to such a noise component. This is very useful because no malfunction occurs even when the tapes are reproduced by different methods. In this embodiment, since the frequency of the identification signal is recorded in the audio track and is selected as a frequency that can be reproduced there, a signal similar to the identification signal may exist in the audio signal. Even in such a case, the use of such determination circuits 81 and 83 does not cause an erroneous response to such an audio signal.

6 is a circuit diagram showing another example of the determination circuits 81 and 83. In this sixth embodiment, a signal of 15 Hz from the input terminal 80 is applied to the first integrating circuit 107 through the diode 117 and to the second integrating circuit 109 through the resistor 118. The same applies to the third embodiment except that. Therefore, the components that perform the same function are denoted by the same reference numerals, and description of the operation of this circuit is omitted.

In the VTR configured as described above, when the stereo audio multiplexed television signal is given to the decoder 13, the output signal A becomes high level, the switch 53 is closed, and the identification signal generating circuit 35 The first identification signal I1 from < RTI ID = 0.0 > 1) < / RTI > is recorded in the second audio track 34 together with the audio signal of the other channel, i.e., the right (R) signal. The identification signal included in the signal reproduced from the second audio track 34 is detected by the determination circuit 81, and a high level determination signal D ₁ is obtained. This determination signal D _{1 is} supplied to the encoder 65 together with the reproduced left (L) signal and right (R) signal, and is converted into a predetermined television multiplexed audio signal and supplied to the RF modulator 59. In the FF modulator, the multiplexed audio signal is FM-modulated to a frequency corresponding to the voice frequency of an empty channel without television broadcasting, and is applied to the output terminal 60, that is, the antenna terminal of the television receiver. In addition, the RF modulator 59 modulates the video signal provided by the video signal reproducing processing unit 57 to a frequency corresponding to the video frequency of the co-channel, and applies it to the antenna terminal of the television receiver.

When the multiplexed audio signal is the Bailing-gal method, the output signal B of the decoder 13 becomes a high level. Accordingly, the switch 55 is closed, and the second identification signal I ₂ at 20 Hz from the identification signal generation circuit 35 is applied to the tape 10 together with the audio signal of the other channel, that is, the negative S signal. 2 is recorded on the audio track 34. And a second second identification signal (I2) of 20Hz contained in the reproduction signal from the audio track 34 is detected by the decision circuit 83, it is derived is a high-level decision signal (D _2). The encoder 65 is provided with the main M signal of one channel and the negative S signal of the other channel together with the determination signal D ₂ from the determination signal generation circuit 73, and the encoder 65 ) Generates a Biling Bunting standard television multiplexed audio signal in accordance with the applied main signal, the sub-signal and the identification signal D ₂ , and gives it to the RF modulator 59. The RF modulator 59 creates an RF signal corresponding to the empty channel without television broadcasting as in the case of the stereo system described above.

The following second table shows the contents of the signals recorded in the voice tracks 24 and 34 for each system. In this second table, L: left signal, R: right signal, M: main signal, S: negative signal, Mo: monaural signal, I1: first identification signal and I2: second identification signal.

[Table 2]

In the above-described embodiment, the identification signal I1 or I2 is recorded only in the second audio track 34. However, in another embodiment, the identification signal I1 or I2 may be recorded on both the first and second voice tracks 24 and 34, or may be recorded only on the first voice track 24. FIG. . Such modifications can be easily made by those skilled in the art as needed.

In addition, the frequency of the identification signal is not limited to 15 Hz or 20 Hz, and can be arbitrarily selected as long as it does not interfere with audio signals. For example, in the PAL method, the vertical synchronization signal (Vsync) is 50 Hz. What is necessary is just to use the division ratio suitable for the frequency divider 39 and 41 contained in the identification signal preparation circuit 35. FIG.

7 is a block diagram showing a modified embodiment of the first embodiment more preferred. In this FIG. 7 embodiment, the same reference numerals are given to components or circuits that perform the same functions as the 7th embodiment, and the main points of the FIG. 7 embodiment will be mainly described. This seventh embodiment has a feature of the determination signal generating circuit 73.

The determination signal generating circuit 73 of the FIG. 7 embodiment includes two amplifiers 75 and 76 which receive a reproduction signal from the second audio track 34 via the equalizer 67. FIG. The output of the amplifier 75 is provided to the bandpass filter 77 which passes the 15 Hz signal, and the output from the amplifier 76 is given to the bandpass filter 79 which passes the 20 Hz signal. In addition, the amplifier 76 may be omitted, and similarly to the first embodiment, the two band filters 77 and 79 may be configured to receive the output of the amplifier 75 together. The outputs of the bandpass filters 77 and 79 are provided to the determination circuits 81 'and 83', respectively. On the other hand, the identification signals I1 and I2 from the identification signal generation circuit 35 are provided to the determination circuits 81 'and 83'. In short, the determination circuits 81 'and 83' compare the phases of the normal identification signals I1 and I2 with the outputs of the band filters 77 and 79 to the noise component or other audio components. This prevents malfunction.

The determination circuits 81 'and 83' are substantially the same, and one determination circuit 81 'will be described with reference to FIG. The judging circuit 81 'is a multiplier having one input connected to the output terminal 47 of the identification signal generating circuit 35 and the other input connected to the output of the input terminal 80, that is, the band filter 77. 129. The multiplier 129 is an analog multiplier, for example, an integrated circuit TA7320P manufactured by Tokyo Ohshibaudenen Co., Ltd. can be used. The output of the multiplier 129 is a low pass filter 107 ′ which passes a frequency of 15 Hz, which is a fundamental wave component of the first identification signal I1, receives the output of the low pass filter 107 and passes the fundamental wave component. A high pass filter 131 for blocking low frequency components and a rectifying circuit 133 for rectifying the output of the high pass filter 131 are applied to the base of the transistor 111 '. The transistor 111 'flows the 15 Hz signal from the diode 117 to the potential or provides the smoothing circuit 109' according to the output level of the rectifier circuit 133. The output of the smoothing circuit 109 'is fed to the + input of a comparator 115, such as an operational amplifier. A reference voltage 113 is applied to the − input of the comparator 115.

When the original identification signal I1 is input to the determination circuit 81 'from the output terminal 47 together with the reproduction signal of 15 Hz from the input terminal 80, the output of the low pass filter 107' is set to the ninth ( A signal of a constant level as shown in region Q of Fig. a) is obtained. This is because there is a constant phase relationship between the original identification signal I1 and its reproduction signal.

When the output of the bandpass filter 77 is 15 Hz but is not a reproduced identification signal but contains only the pseudo signal, the phase relationship between the original identification code from the terminal 47 and the weft signal is negative. At the output of the low pass filter 107 ', an alternating signal as shown in the region P in Fig. 9A is obtained. In this way, the base of the switching transistor 111 'is given a high level when the true identification signal is being reproduced and a low level when the pseudo identification signal is given. Therefore, the + input of the comparator 115 is given a signal as shown in FIG. 9 (b), and the negative input of the comparator 115 is set as shown by the dotted line 127 'in FIG. 9 (b). Only in the region Q of 9 degrees, i.e., when the true identification signal is reproduced, the high-level determination signal D1 is obtained. In other words, by using the multiplier 129 or other related circuits, it is possible to compare the phase between the original identification signal and the reproduction signal, and thereby determine whether or not the true identification signal is reproduced. The malfunction caused by the noise component is effectively prevented.

FIG. 10 is a circuit diagram showing another example of the determination circuit used in the FIG. 7 embodiment. This FIG. 10 embodiment is the same as the FIG. 8 embodiment except that the gate 135 is used instead of the multiplier 129 of the FIG. 8 embodiment. The gate circuit 135 uses a square wave of 15% (or 20 Hz) at 15 Hz (or 20 Hz) corresponding to the identification signal I1 or I2 from the identification signal generation circuit 35 as the gate signal. As such a gate signal, an appropriate frequency divider output of the frequency divider included in the identification signal generation circuit 35 may be used, and an appropriate frequency divider output of the frequency divider included in the identification signal generation circuit 35 may be used as the gate signal. This gate signal is provided at the output terminal 47 '. The other input of the gate circuit 135 is provided with an output signal of the band filter 77 at the input terminal 80, i. Since the reproduced identification signal has a constant phase relationship with respect to the gate signal, that is, the original identification signal I1 or I2, the output of the gate circuit 135 and the output of the low pass filter 107 'and the high pass filter 131 ) Outputs the same as that of Fig. 11 (a), 11 (b) and 11 (c) in Fig. 11, respectively. That is, the areas of the + and-components of the output of the high pass filter 131 become equal. Therefore, the output of the rectifier circuit 133 is 0, the switching transistor 111 'is cut off. Therefore, the reproduced identification signal from the input terminal 80 is applied to the smoothing circuit 109 'via the diode 117, smoothed by the circuit 109', and applied to the + input of the comparator 115. . For this reason, the high level identification signal D1 or D2 is obtained at the output terminal 116 of the comparator 115.

On the other hand, when the reproduction signal applied from the input terminal 80 does not include the true identification signal I1 or I2, the output of the gate circuit 135, the output of the low pass filter 107 'and the high pass filter The output of 131 becomes the 11th (a '), the 11th (b'), and the 11th (c '), respectively. As is apparent from FIG. 11 (c '), the areas of + and-components of the output of the high pass filter 131 are different, and the output of the rectifier circuit 133 is positively +, and the switching transistor 111' ) Is on. Therefore, the pseudo-identification signal to be applied to the smoothing circuit 109 'via the diode 117 flows into the ad potential, so that the output terminal 116 of the comparator 115 becomes low level.

Even in the above-described embodiment, in detecting the identification signal, even if a noise component that may be obtained when the recorded tape is reproduced without using the method of the present invention is transmitted, for example, the noise component may not respond to such noise component, resulting in malfunction. Can be effectively prevented.

Of course, in the seventh embodiment, the same modifications as in the first first embodiment can be easily understood by those skilled in the art.

12 is a block diagram showing another embodiment of the present invention. This embodiment differs from the embodiment shown in FIGS. 1 and 2 in that the information is included in the phase of the identification signal, whereas the system information is included in the frequency of the identification signal.

The audio signal D of the other channel from the decoder 13 is provided to the audio signal recording processing unit 29 via the band filter 25 'and the mixer 27. The band filter 25 'has a pass band of, for example, 50 Hz to 15 KHz. This band filter 25 'may be replaced with a high pass filter having a pass band of a frequency higher than 50 Hz, for example, as in the previous embodiment. That is, the band filter 25 'serves to block or attenuate the audio signal of the frequency band to which the identification signal from the identification signal generation circuit 35' of the other channel overlaps.

The identification signal creation circuit 35 'is configured as including a switch circuit corresponding to the switch circuit 51 in the first embodiment, and details thereof are shown in FIG. Referring to FIG. 14, the identification signal generating circuit 35 'includes an input terminal 143, which receives a square wave signal from the waveform shaping circuit 91, i.e., the selection circuit 95. As shown in FIG. . This square wave signal has a frequency of 30 Hz and is applied to the low pass filter 145. The low pass filter 145 has a cutoff frequency of 30 Hz, for example, and has a time delay α, and the output of the low pass filter 145 is connected to the output terminal 149 via a switch 147. The output of the low pass filter 145 is also connected to the output terminal 149 through a series circuit of the inverter 151 and the switch 153. The identification signal preparation circuit 35 'again has input terminals 155 and 157, and the input terminal 155 is supplied with the output signal A from the decoder 13 and the output terminal 157 is output. Signal B is given. The switches 147 and 153 are energized when the signals A and B applied at the input terminals 155 and 157 are high level, and are cut off when they are low level.

Here, with reference to FIG. 13A, the operation of this identification signal generating circuit 35 'and the description of what signals are recorded in each system in the second audio track 34 of the data 10 (FIG. 2) will be described. do. FIG. 13A shows a vertical synchronization signal Vsync and FIG. 13B shows a 30 Hz square wave signal from the selection circuit 95. When the audio signal to be recorded is in the stereo system, the high level output signal A is applied to the input terminal 155 of the identification signal generating circuit 35 'by the decoder 13. Therefore, in the stereo system, the switch 147 is closed and the switch 153 is open. The square wave signal applied from the input terminal 143 is applied to the low pass filter 145, and only one low phase α is delayed with respect to the square wave signal by the low pass filter 145. The first identification signal shown is output. This first identification signal is derived to the output terminal 149 via the switch 147.

)지연된 것이된다. 이와같이 해서 바일링갈방식에서는 출력단자(149)에 제13a도(C-2)에 나타낸 바와 같은 제2식별신호가 얻어진다.In the case where the audio signal to be recorded is the Bailingal method, the high-level output signal B is applied to the input terminal 157 of the identification signal generation circuit 35 'by the decoder 13. For this reason, the switch 153 is closed and the switch 147 is opened in the bailing gal system. On the other hand, the sinusoidal wave signal of 30 Hz from the low pass filter 145 is found by the inverter 151. Therefore, the output sine wave signal from the inverter 151 has a predetermined phase (α +) with respect to the reference signal, that is, the square wave signal.

It becomes delayed. In this way, the second identification signal as shown in Fig. 13A (C-2) is obtained at the output terminal 149 in the bailing gal system.

When the audio signal to be recorded is a monaural system, the output signals A and B from the decoder 13 remain at the low level together, and the switch 147 included in the identification signal generation circuit 35 '. And 153 remain open together. Therefore, in the monaural method, no special identification signal is derived from the output terminal 149 of the identification signal generating circuit 35 'as shown in Fig. 13A (C-3).

When the first identification signal as shown in FIG. 13 (C-1) in the stereo system is also the Bailingal system, the second identification signal as shown in FIG. It is derived from the preparation circuit 35 '. The identification signal from this identification signal creation circuit 35 ' To the mixer 27 and superimposed thereon on the audio signal D of the second channel. In the mixer 27 ', frequency multiple signals as shown in (D-1), (D-2) or (D-3) in FIG. 13A are derived in each manner. Such a frequency multiplex signal is provided to the second audio head 33 via the audio signal recording processing unit 29 and the switch 31. As a result, frequency multiple signals as shown by (D-1) (, D-2) or (D-3) in FIG. 13A are recorded on the second audio track 34 of the tate 10 (FIG. 2). do.

Next, the reproduction system will be described. In this reproducing system, the determination signal generating circuit 73 'is different from the first embodiment described above. The determination signal generating circuit 73 'includes two input terminals 159 and 161, and one input terminal 159 has a second audio track 34 by the sound head 33 in the equalizer 67. Is also given to the frequency capstan servo circuit 105 reproduced by the " A frequency multiplex signal (shown in FIG. 13A (D-1), (D-2) or (D-3)) from the equalizer 67 is provided to the band pass filter 163. The band filter 163 is for extracting an identification signal from the reproduced frequency multiplex signal and has a time delay θ. Therefore, the output of the band filter 163 is a stereo identification, a bialgal or monaural method, as shown in (E-1), (E-2) or (E-3) of FIG. 13B, respectively. It has a phase delay of θ with respect to. Meanwhile, the square wave signal from the input terminal 161 is applied to the low pass filter 165. This low pass filter 165 has the same time delay as β as the low pass filter 165 and the low pass filter 145 (Fig. 14). Therefore, the output sine wave signal of the blowrose filter 165 has a phase delay of β as compared with the square wave signal applied from the input terminal 161 as shown in Fig. 13B (G). The output of the low pass filter 165 is again given to the phase adjusting circuit 167. The phase adjustment circuit 167 outputs the output signal of the low pass filter 165 so that the phase of the output of the low pass filter 165 and the reproduced first identification signal included in the output of the band pass filter 163 coincide with each other. It is for adjusting the phase of the meeting and has an ideal amount of γ. Therefore, the output of the phase adjustment circuit 167 has a phase delay of (β + γ) with respect to the square wave signal as shown in Fig. 13B (H). The identification signal determination circuit 73 'again includes a multiplication circuit 169 and the multiplication circuit 169 outputs the output of the low pass filter 163 (Fig. 13B (E-1), (E-2) or ( Multiplied by the output of the phase adjusting circuit 167 (denoted by B (H) in FIG. 13B). At the output of the multiplication circuit 169, the signal shown by the line I-1 in Fig. 13B (I) is obtained, and the signal represented by the line I-2 is obtained in the Bailingal method. In the monaural system, only an AC voltage component (direct current) is obtained without obtaining any AC signal at the output of the multiplication circuit 169.

The output of the multiplication circuit 169 (indicated by B (I) in FIG. 13B) is provided to the determination circuit 171. This determination circuit 171 is for judging what kind of multiplexing audio signal is reproduced at that time in accordance with the signal from the multiplication circuit 169, and the details thereof are shown in FIG.

Referring to Fig. 16, the determination circuit 171 has an input terminal 173, which has signals from the multiplication circuit 169 ((I-1) and (I-2 in Fig. 13B). ) Or (indicated by (I-3)). A condenser 175 for averaging or integrating the output of the multiplication circuit 169 is connected to the input terminal 173, and the terminal voltages of the condenser 175 are comparators 177 and 179, such as operational amplifiers, respectively. Is given to the + input and-input of. The first reference level set by the variable resistor 181 is applied to the-input of the comparator 177, and the second reference level set by the second variable resistor 183 is applied to the + input of the comparator 179. It is authorized. Comparator 177 is for determining the stereo system and comparator 179 will be for determining the Bayingal method. In the stereo system, the signal from the multiplication circuit 169 appears as (I-1) in FIG. 13B. Therefore, the terminal voltage of the capacitor 175 becomes (V _b ) shown in FIG. 13B. Therefore, as the reference level of the first by the variable resistor 183, the voltage applied to leave a slightly smaller level than the voltage (V _b), it is possible to determine a stereo system by the comparator (177). In addition, the signal from the multiplication circuit 169 becomes as shown in Fig. 13B (I-2), and the terminal voltage of the capacitor 175 becomes the level shown in Fig. 13B (Vb). Therefore, when the potential having a level slightly higher than the voltage Vq is applied as the second-level reference level by the variable resistor 183, the comparator 179 can determine the Bailing-gal method. In the monaural system, the signal level from the multiplication circuit 169 is shown in FIG. It has a level represented by (V _m ), and thus the terminal voltage of the capacitor 175 is also equal to this voltage (V _m ). This voltage V _m does not obtain a high level signal, that is, a determination signal, in either of the comparators 177 and 179. In this way, in the stereo system, a high level determination signal is obtained from the output terminal 181 of the determination circuit 171, and a high level determination signal is obtained from the output terminal 183 in the bilingal system. No output signal is obtained at either of the two output terminals 181 and 183.

Here, the overall operation of this determination signal generation circuit 73 'will be described in more detail. First, the case where the first identification signal (denoted by Fig. 13A (C-1)) showing the stereo system is recorded on the second audio track 34 (Fig. 2) will be described. In the audio head 33, a frequency multiplex signal as shown in FIG. 13A (D-1) is reproduced, and the reproduced signal is converted into the first identification signal (FIG. 13B (E-1) by the band filter 163). Are displayed). At this time, the output of the filter 163 has a phase delay of (α + θ) with respect to the reference square wave signal (indicated by A (B) in FIG. 13A). The capstan motor (not shown) is controlled by the capstan servo circuit 105 so that the control signal reproduced by the control head 101 is in phase with the control signal at the time of recording, that is, the signal shown in FIG. 13A (B). Since the reproduced control signal is applied to the waveform shaping circuit 103, a square wave signal of the same phase as that shown in FIG. 13A (B) as shown in FIG. 13B (F) can be obtained. The square signal from the waveform shaping circuit 103 is applied to the insertion circuit 169 via the low pass filter 165 and the phase adjusting circuit 167. The low pass filter 165 and the phase adjustment circuit 167 have phase delays of β and (β + γ), respectively. Since the delay amount γ is set to be γ = α + θ + β, the outputs of the bandpass filter 163 and the phase adjustment circuit 167 are the same as each other. Therefore, at the output of the multiplication circuit 169, the signal shown in Fig. 13B (I-1) is obtained. The signal becomes the terminal voltage of the capacitor 175 of the determination circuit 177, (V _s ), and the voltage (V _s ) exceeds the lower limit level of the comparator 177. A determination signal indicating that the stereo system is obtained is obtained.

In the bailingal method, a phase of a signal signal as shown in FIG. 13B (E-2), that is, a signal shown in FIG. 13B (E-1), is output to the output of the band filter 161 of the determination signal generation circuit 73 '. This inverted signal is obtained. The signal from the band filter 163 also has a phase inverted relationship with respect to the output signal from the phase adjusting circuit 167. Therefore, a signal as shown in Fig. 13B (I-2) is obtained at the output of the multiplication circuit 169. Therefore, the determination terminal voltage of the capacitor 175 of the circuit 171 turns believe that the voltage (V _b) shown in Figure 13b is that the threshold level of the voltage (V _b) a comparator (179), as described above. Thus, a determination signal indicating that the high level Bailinggal method is reproduced is obtained at the output of the comparator 179.

When the monaural system is reproduced, no signal is obtained at the output of the band filter 163. Therefore, even if the output of the phase adjustment circuit 167 and the output of the band pass filter 163 are added by the addition circuit 169, only the bias voltage which does not contain an AC component is output as the output. Therefore, as described above, the terminal voltage of the capacitor 175 (Fig. 16) becomes the voltage V _m shown in Fig. 13B, and this voltage V _m is the respective voltages of the comparators 177 and 179, respectively. Since it is in the middle of the threshold level, from either of the two comparators 177 and 179, a high level signal is not obtained, and as a result, it is determined that the audio signal reproduced is monaural.

FIG. 17 is a waveform diagram for explaining the effect of the FIG. 16 embodiment, and particularly, shows the voltages across the capacitor 175 (FIG. 16). In FIG. 17, the region I is a portion in which the multiplexed voice signal is recorded as the stereo type, and the first identification signal is recorded. Are shown respectively. The area III shows a monaural system in which no identification signal is recorded. The area IV shows a case where the second audio track 34 (FIG. 2) is recorded and the frequency is sufficiently low as an audio signal, not according to this embodiment. As can be seen from FIG. 17, the stereo method, the bailing galle method, or the monaural method are set by reference levels 181 'and 183' set to the variable resistors 181 and 183 (FIG. 6). Can be distinguished clearly. Also, even in the case where an audio signal including a low frequency component is reproduced without resorting to this embodiment, i.e., no identification signal is recorded, the reproduction level, i.e., the terminal voltage of the capacitor 275 (Fig. 16) is determined at the determination level 181 '. ) And (183 ') so that there is no fear of malfunction due to such low frequency components other than the identification signal.

On the other hand, in Fig. 18, malfunction is caused by low frequency components rather than identification signals. This FIG. 18 shows an example in the case where only the low frequency signal is detected or not, according to the FIG. 12 embodiment. That is, when the multiplication circuit 169 (FIG. 15) is not used as in this embodiment, as shown in FIG. 18, the capacitor 175 (FIG. 16) is reproduced by the reproduced low frequency signal existing in the region (VI). The terminal voltage of?) Causes a portion exceeding the reference level 181 ', and derives a stereo determination signal similarly to the region V. FIG. Derivation of the stereoscopic determination signal in this area VI is an obvious malfunction. However, according to the twelfth embodiment, malfunctions as shown in FIG. 18 can be effectively prevented.

진상회로(36)가 형성된다. 식별신호 작성회로(35")는 제14도 실시예와 대체로 마찬가지인 동작을 행한다. 즉 식별신호 작성회로(35")는 스테레오 방식의 경우 제13a도의 (C-1)으로 나타낸 바와 같은 30Hz의 정현파신호를 제1식별신호(I1)로서 도출하고, 바일링갈방식인 때 출력단자(149)에서 제13a도(C-2)로 나타낸 바와 같은 위상반전된 제2의 식별신호(I2)를 도출한다. 그리고, 모노럴방식에서는 이 식별신호작성회로(35")에서는 아무런 신호도 얻지 못한다.

/2진상회로(36)는 예를들면 미분회로로 구성되고 그출력으로서 제1식별신호와 제1식별신호와 제2식별신호와의 중간적인 위상관계에 있는 별개의 식별신호(I3)를 출력하는 것이다. 이 식별신호 작성회로(35")의 출력단자(149)로부터의 제1 또는 제2의 식별신호(I1) 또는 (I2)는 믹서(16)에 부여되고,

/2진상회로(36)로부터의 별개의 식별식호(I3)는 믹서(27)에 부여된다. 따라서 제1음성트랙(24) 및 제2음성트랙(34)(제2도)에는 제21도의 (D) 및 (E)로 나타낸 바와같은 제1식별신호(I1) 또는 (I2)및 (I3)이 대응하는 채널의 음성신호와 함께 기록된다.19 is a block diagram showing another embodiment of the present invention. This FIG. 19 embodiment is the same as that of the FIG. 12 embodiment in that the information indicated by the scheme as a modification of the FIG. 12 embodiment is included in the phase component of the phase sign of the identification signal. In this FIG. 19 embodiment, the identification signal is recorded on both of the two audio tracks 24 and 34 of the tape 10 (FIG. 2). For this purpose, the band filter 14 and the mixer 16 are inserted in the path of the audio signal of one channel from the decoder 13. In addition, in order to superimpose the identification signal on the audio signals of the two channels, the identification signal generating circuit 35 "and / 2

The fastening circuit 36 is formed. The identification signal generation circuit 35 "performs substantially the same operation as in the embodiment of Fig. 14. That is, in the case of the stereo system, the identification signal generation circuit 35" is a sine wave of 30 Hz as shown by (C-1) in Figure 13a. A signal is derived as the first identification signal I1, and a phase-inverted second identification signal I2 as shown in FIG. . In the monaural method, no signal is obtained by this identification signal generation circuit 35 ".

The / 2 phase shift circuit 36 is composed of, for example, a differential circuit and outputs a separate identification signal I3 having an intermediate phase relationship between the first identification signal and the first identification signal and the second identification signal as its output. It is. The first or second identification signal I1 or I2 from the output terminal 149 of this identification signal generation circuit 35 "is provided to the mixer 16,

A separate identification code I3 from the / 2 advance circuit 36 is given to the mixer 27. Therefore, the first audio track 24 and the second audio track 34 (FIG. 2) include the first identification signals I1 or I2 and I3 as shown in FIGS. 21D and 21E. ) Is recorded together with the audio signal of the corresponding channel.

/2지연상회로(168)를 통해서 꼽셈회로(169')에 부여된다.

/2지연상회로(168)는 예를들면 적분회로로 이루어지며, 대역필터(166)의 출력을

/2만큼 상을 지연시킨다. 제21(f)도에 나타낸 바와같이 스테레오방식 및 바일링갈방식 즉 영역(X) 및 (Y)에서는 대역필터(140')의 출력에는 상호

만큼 위상이 상이한 제1의 식별신호(I1) 및 (I2)가 포함된다. 한편

/2지연상회로(168)의 출력은 제21(g)도에서 나타낸 바와같이 제2음성트랙(34)에 기록된 별개의 식별신호(I3)(제21(e)도로 표시함)가

/2만큼 상이 지연된 신호성분을 포함한다.Next, the reproduction system will be described. The reproducing system includes a determination signal generation circuit 73 ". The input terminals 151 'and 161' included in this determination signal generation circuit 73" are supplied from the equalizers 61 and 67, respectively. A reproduction signal of the first audio track 24 and a reproduction signal of the second audio track 34 are received. The band filter 140 'is for extracting the first or second identification signal from the reproduction signal provided from the input terminal 151'. The reproduction signal from the equalizer 67 provided at the input terminal 161 'is supplied with a band filter 166 and

Through the / 2 delay phase circuit 168 to the addition circuit 169 '.

The / 2 delay phase circuit 168 is formed of, for example, an integrated circuit, and outputs the output of the band pass filter 166.

Delay phase by / 2 As shown in FIG. 21 (f), in the stereo system and the bialgal method, that is, in the regions (X) and (Y), the output of the bandpass filter 140 '

The first identification signals I1 and I2 which are different in phase from each other are included. Meanwhile

The output of the / 2 delayed phase circuit 168 is provided by a separate identification signal I3 (indicated by the 21st (e) diagram) recorded in the second audio track 34 as shown in FIG. 21 (g).

Includes signal components whose phase is delayed by / 2.

Therefore, in the stereo system, since the identification signals I1 and I3 input to the multiplication circuit 169 'are in the same phase, a signal as shown by the line X in FIG. 23 is obtained from the multiplication circuit 169'. Lose. On the contrary, in the Biingal method, the identification signals I2 and I3 applied to the trimming circuit 169 'are inversely related to each other. In the summation circuit 169', a signal as shown by the line Y in FIG. 23 is obtained. Lose. In addition, since no signal is recorded in the first audio track 24 in the monaural method, that is, in the region Z, a separate identification signal I3 is recorded only in the second audio track 34. Signal as shown by the dotted line Z in FIG. In this manner, the output of the multiplication circuit 169 'obtains an AC signal as shown by lines X, Y, or 23 of FIG.

Thus determined both-end voltage of the capacitor 1175) included in the circuit (171 ') has a 21 (h), a clearly different levels (Y _x according to the stereo mode, mobile ringgal scheme and monaural scheme as shown also), (Y _y ) And (V _z ). Therefore, in the comparator 177, when the stereo system is used, a high level determination signal is obtained. A high level determination signal is obtained from the comparator 179 in the case of the bailing gal system, and a high level signal cannot be obtained in either of the two comparators 177 and 179 in the monaural manner.

21 (a), 21 (b) and 21 (c) are shown in contrast to the case of the twelfth embodiment.

According to the embodiment of Fig. 19, even if the mounting position of the heads 23, 33, and 101 or the position of the heads 23 and 101 is slightly different, the detection of the wrong manner is very effective. That is, in the general VTR, the distance between any one of the voice tracks and the control track 102 is much larger than the distance between the first and second voice tracks 24 and 34 (FIG. 2). . Therefore, in consideration of the general attachment accuracy of the head, the distance between the audio head and the control head tends to vary greatly from model to model or from set to set. Phase shift may occur with respect to the reproduction identification signal. Therefore, when the reproduction control signal is used as the reference phase signal of the determination signal generation circuit as shown in Fig. 12, such accurate head position adjustment is required. On the other hand, in the nineteenth embodiment, since the reproduction control signal is not used for the determination of the system, it is not necessary to consider such an imbalance in the position precision and is very useful. That is, in the nineteenth embodiment, the first or second identification signals I1 or I2 that are in phase with each other indicating the scheme on the first audio track are recorded, and the first and the second audio tracks are recorded on the second audio track. Since a separate identification signal I3 having a phase corresponding to the middle phase of the identification signal is recorded and the separate identification signal I3 is used as a reference phase signal, the position of each control head and the mounting error It does not affect the off of the haze. In this embodiment, therefore, a system automatic determination system having excellent compatibility is obtained.

/4만큼 다르게 하고 별개의 식별신호를 그 중간위상의 벗어짐을 갖게 설정하도록 변결하고 그와 같은 변경에 따라서 판정신호 발생회로를 수정해도 마찬가지의 효과가 얻어진다는 것을 물론이다. 이와 같은 변형 내지 수정은 당업자가 용이하게 이룰 수 있는 것이다.Further, in the nineteenth embodiment, the phases of the first and second identification signals are

It is a matter of course that the same effect can be obtained even if the difference is set by / 4 to be set so that a separate identification signal is set to have its intermediate phase deviated, and the determination signal generating circuit is modified in accordance with such a change. Such modifications or variations can be readily made by those skilled in the art.

Although all the above embodiments were embodiments of the NTSC system, the present invention can of course be used in a PAL system.

In the above description, the embodiment in which the method identification signal is recorded in the voice sound track together with the voice signal has been described. However, the present invention can be modified as follows. That is, the method identification signal may be recorded in the video track together with the video signal, the method identification signal may be extracted from the video track, and the stereo system, the signaling method, or the monaural system may be determined according to the extracted identification signal. In this case, since the frequency band that can be recorded on and played back on the video track is wide, the identification signal included in the standard television broadcast wave may be recorded as it is, not limited to the low frequency signal sometimes as a system identification signal.

Claims (20)

Recording medium 10 including voice tracks 24, 34 and video tracks 12, 14 and video track recording means 9, 11 for recording video signals on the video tracks 12, 14; ) And recording means 23 and 33 for recording the audio signal corresponding to the video signal to the audio tracks 24 and 34 and the audio signal are different in multiplexing manner, i.e., stereo, in response to the video signal to be recorded. The method identification signal generating means 35, 35 'and 35 " and the method identification signal for generating a method identification signal of a relatively low frequency are recorded in the method Bailingal method or the monaural method. The video signal from the video signal 12 and 14 and the identification signal granting means 51, 27, 36, 27 'for giving the voice track recording means 23, 33 together with the voice myths. The video track playback means 9 (11) and the audio tracks 24 and 34 for playing back the voice The method of the voice signal in accordance with the method identification signal included in the voice track reproducing means 23 and 33 for reproducing the call and the method identification signal, and the reproducing signal from the voice track reproducing means 23 and 33. And a decision signal generating means (73) (73 ') (73 ") for generating to a decision signal indicating a signal. 2. A method according to claim 1, in accordance with a sound signal from said sound track reproducing means (23) and (33) and a decision signal from said decision signal generating means (73) (73 ') (73 "). A video signal recording / reproducing apparatus comprising multiplexing means (65) for producing a multiplexed speech signal in a Bailingal or monaural manner. The video signal reproduction processing means (57) according to claim 2, characterized in that the video signal reproduction processing means (57) for configuring the reproduced video signal from the video track reproduction means (9) and (11) as a television signal, and the video signal reproduction processing means (57). And an RF modulator means (59) for generating a standard radio frequency television signal according to the signal-processed video signal of the signal and the multiplexed voice signal from the multiplexing means (65). 4. The voice track according to claim 1, wherein the voice track comprises first and second voice tracks (24) and (34), and the voice track recording means comprises two substantially different voices in the stereo method and the bailingal method. And two audio recording heads 23 and 33 for recording the audio signal of the channel or the audio signal of two channels which are substantially the same in the monaural manner to each of the first and second voice tracks. The voice track reproducing means includes two voice reproducing heads 23 and 33 corresponding to each of the first and second voice tracks. Video signal recording, characterized in that at least one of the audio signals of the two channels is recorded on at least one of the second audio tracks 24 and 34 by at least one of the two audio recording heads. / Playback device. 5. The audio recording head and the audio reproduction head comprise two common audio heads 23 and 33, and the audio signals to be recorded are given to the two audio heads, And two switch means (21) (31) for imparting the reproduced signal from the sound head to the determination signal generating means (73) (73 ') (73 ") and the multiplexing means (65). A video signal recording / playback device. 5. The method according to claim 4, wherein the method identification signal generating means (35) is a first and second frequency signal for generating a first or second frequency signal of different frequencies in the two selected methods of the three methods. Generating means 39 and 41 and said sound track recording means 33 records corresponding ones of the first or second frequency signals according to one or the other of the selected two methods and identifies in the remaining method. The signal is not recorded and the determination signal generating means 73 is either a method when the first frequency signal is present at the voice track regeneration stage and another method when the second frequency signal is present. And a judging means (81) (83) for generating a judging signal indicative of the remaining manner when none of the frequency signals of the < RTI ID = 0.0 > . 7. The apparatus of claim 6, wherein the determination signal generating means (73) comprises a first band filter (77) having a pass band corresponding to the first frequency signal, and a pass band corresponding to the second frequency signal. Two band filters 79 and one of the first and second band filters 77 and 79, respectively, to be mounted to detect the level of the first frequency signal and the second frequency signal. And a means (115). The method according to claim 6, wherein the first frequency signal from the method identification signal generating means 35 and the first frequency signal reproduced from the voice track reproducing means 33 are compared in phase or the method identification signal Phase comparison of the second frequency signal from the producing means 35 with the second frequency signal reproduced from the voice track reproducing means 33 determines whether or not the reproduced frequency signal is a normal frequency signal. And a means (107) (111) (129) (135). 9. The apparatus of claim 8, wherein the determination signal generating means includes: a first band filter 77 having a pass band corresponding to the first frequency signal and a second band having a pass band corresponding to the second frequency signal. Means 115 for being associated with each of the filter 79 and the first and second bandpass filters 77 and 79, for detecting the level of the respective outputs of the first and second bandpass filters, and And a means (111) (111 ') for prohibiting the transmission of the frequency signal to the level detecting means (115) in accordance with the output of the determining means (107) (111) (129) (135). Signal recording / playback device. The multiplication means (129) according to claim 9, wherein said determination means receives, as two inputs, the frequency signal from the method identification signal generating means (35) and the regenerated frequency signal from the band filter (77) (79). Video signal recording / reproducing apparatus comprising a. 11. The method of claim 10, wherein the prohibiting means includes: a low pass filter 107 'receiving the output of the multiplication means 129, a high pass filter 131 receiving the output of the low pass filter 107', and the high pass. The bandpass filter 133 receives the output of the filter 131 and is interposed between the bandpass filters 77 and 79 and the level detecting unit 115 and the bandpass filter in accordance with the output of the rectifier circuit 133. And switching means (111 ') for preventing the transfer of a signal from said signal to said level detecting means from said video signal recording / reproducing apparatus. 10. The apparatus according to claim 9, wherein the determining means receives a gate means 135 which receives, as its two inputs, the frequency signal from the method identification signal generating means 35 and the reproduced frequency signal from the band pass filters 77 and 79. Video signal recording / reproducing apparatus, characterized in that it comprises a. The high pass filter 131 and the high pass of the low pass filter 107 ′ receiving the output of the gate means 135 and the high pass filter 131 receiving the output of the low pass filter 107 ′. A rectifying circuit 133 which receives the output of the filter 131, and is interposed between the band pass filters 77 and 79 and the level detecting means 115 and according to the output of the rectifying circuit 193. And a switching means (111 ') for preventing the transmission of the signal from the filter to the level detecting means. 6. The video signal according to claim 5, wherein the video signal includes a ten-vision signal having a synchronization signal, and wherein the first and second frequency signal generating means each include first and second frequency signals having different frequencies according to the synchronization signal. And a dispensing means (39) (41) for generating a video signal recording / reproducing apparatus. The method of claim 1 to claim 4, wherein the method identification signal generating means (35 ') is a phase signal generating means (147) for generating an identification signal in which the information indicating the stereo method, the signaling method or the monaural method is included in the phase. And (151) and (153). 16. The apparatus according to claim 15, wherein said determination signal generating means (79 ') (79 ") determines the phase of the identification signal reproduced by said voice track reproducing means (23) (33), and performs the stereo, biiling, or monaural method. And a phase detecting means (169) (171) for determining a function of the video signal. 17. The apparatus according to claim 16, further comprising reference phase signal blowing means (103) (161) (165) (167) (67) (166) (168) for imparting a reference phase signal. And means (169) for performing phase comparison with said reference phase signal. 18. The apparatus of claim 17, wherein the reference phase signal generating means waveforms a control head (101) for reproducing a control signal in a control track formed on the recording medium (10), and a reproduced control signal from the control head (101). And a means (109) for shaping. 18. The apparatus according to claim 17, wherein the method identification signal generating means includes means for generating a separate identification signal having a phase corresponding to an intermediate phase of the first and second identification signals, and wherein the determination signal generating means is reproduced. And means (169) for using a separate identification signal as said reference phase signal and detecting a phase of the reproduced first or second identification signal. Means for recording a voice signal on a recording medium; said voice signal is recorded in a different multiplexing manner, i.e., stereo, bijingal or monaural, and means for recording on said recording medium a mode identification signal indicative of the direction of said voice signal. Means for reproducing the audio signal on the recording medium, means for reproducing the system identification signal on the recording medium, and generating a determination signal indicative of the method of the audio signal recorded according to the reproduced system identification signal. And means for producing a multiplexed audio signal according to the reproduced audio signal and the determination signal, i.e., a stereo system, a Bailingal system or a monaural system.

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