JPH01105301A - Magnetic recording device and magnetic recording/ reproducing device - Google Patents

Abstract

PURPOSE:To decrease a noise spectrum in a regenerative signal by mixing a digital sound signal, which is performed with polyphase difference PSK modulation, with a modulated FM sound signal, and recording them together with a high frequency bias signal to a magnetic deep layer. CONSTITUTION:A color video signal in a standard color system incoming to a terminal 25 is supplied through a video signal processing circuit 26 to a synchronizing signal separator circuit 29. A channel analog sound signal and a right channel analog sound signal enter terminals 31a and 31b. The frequencies of the digital sound signal modulated by an offset quadrature difference (OQD) PSK modulator 36 and the output sound signal of FM modulator 73a and 73b are divided and superimposed by a mixer 75, and they are supplied to a bias superimposing circuit 39. The digital sound signal and the FM sound signal, on which the high frequency bias signal removed from the circuit 39 is superimposed, are recorded to the magnetic deep layer part of a magnetic tape 43. Thus, the noise spectrum in the regenerative signal can be decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic recording device and a magnetic recording/reproducing device, and in particular, the present invention relates to a magnetic recording device and a magnetic recording/reproducing device.
Phase difference P S K (Off5et Q uadrat
ure Differential Phase 5
Record or reproduce digital audio signals or frequency-modulated FM audio signals modulated using a polyphase PSK modulation method such as high-keyino (0QDPSK) or four-phase differential PSK (QDPSK), and record video signals in the surface layer. The present invention relates to a magnetic recording device and a magnetic recording/reproducing device for recording or reproducing data.

BACKGROUND ART FIG. 8 is a block system diagram showing a conventional magnetic recording and reproducing device that combines a magnetic recording device and a reproducing system. After being converted into a frequency division multiplexed signal of, for example, a low-pass converted carrier chrominance signal and a frequency-modulated luminance signal, the recording amplifier 3
and the rotating heads 5a and 5 through the switching circuit 4.
b is recorded on the magnetic tape 6.

On the other hand, the left channel (L
The audio signals of the channel) and right channel (Rch) are subjected to pulse code modulation (PCM) by the digital signal processing circuit 9.
After being converted into a signal and time division multiplexed, 0QPS
The signal is modulated by the K modulator 10 using an offset four-phase PSK method, and then recorded on the magnetic tape 6 by the rotary heads 13a and 13b through the recording amplifier 11 and the switching circuit 12, respectively.

Here, the rotary heads 5a and 5b perform frequency division on the audio track in which the 0QPSK modulated digital audio signal is recorded in the deep layer of the magnetic layer of the magnetic tape 6 by the rotary heads 13a and 13b. Multiple video signals are recorded forming video tracks.

During reproduction, the frequency division multiplexed video signal reproduced from the video track by the rotary heads 5a and 5b is supplied to the video signal processing circuit 15 through the switching circuit 4 and the reproduction amplifier 14, where the original reproduced color image is After being returned to a signal, it is output to the output terminal 16.

On the other hand, the digital audio signal reproduced from the audio track by the rotary heads 13a and 13b is transmitted through the switching circuit 12, the reproduction amplifier 17, and the equalizer 18.0QPS.
The digital signal processing circuit 20 passes through the K demodulators 19 respectively.
, where it is converted into a reproduced PCM signal, and then
The signal is returned to the original analog audio signal by the /A converter 21, and the left channel reproduced audio signal and the right channel reproduced audio signal are outputted separately and simultaneously to output terminals 22L and 22R.

As described above, the conventional device shown in FIG. 9 is a rotary head type deep recording type VTR in which a 0QPSK modulated digital audio signal is directly recorded in the deep portion of the magnetic layer of the magnetic tape 6. This recording/reproducing device has already been published in the literature (for example, Arai et al.: “A 5TUDY
ON THEDIGITIZATTON OF
AUDIO5IGNALS FORVIDEOT
EPERECORDER”, Interllat
iollal Confer-enCe On AC
OLIStiC8,5peech, and S
ignalProcessing, p, 29-3
3.1986).

Problems to be Solved by the Invention However, since the above-mentioned conventional device directly records a 0QPSK modulated digital audio signal onto a magnetic tape, which is a non-linear transmission system, cross-modulation distortion occurs, causing distortion during playback. A noise spectrum that was not present during recording occurs in the low frequency conversion carrier color signal band.

For this reason, there is a problem in that the color S/N is degraded by the noise spectrum in the reproduction signal when the rotary heads 5a and 5b reproduce the video tracks.

Also, a rotating head 13a.

There has been a problem in that the error rate of the reproduced digital audio signal deteriorates due to distortion due to nonlinearity of the tape in the reproduced signal when the audio track is reproduced by 13b.

Furthermore, with conventional equipment, video software on which FM audio signals were recorded could not be played back, and in the recorded tape M industry, digital audio was recorded separately from video software on which FM audio was recorded. It is also necessary to prepare video software, which is both time-consuming and uneconomical.

The present invention was created in view of the above points, and aims to provide a magnetic recording device that can reduce the noise spectrum and also record FM audio signals. It is an object of the present invention to provide a magnetic recording and reproducing device that uses a recording device as a recording section and has a reproducing section that can also reproduce FM audio signals.

Means for Solving the Problems The magnetic recording device of the present invention is a deep recording type magnetic recording device, and includes a first modulation device that generates a digital audio signal, and a second modulation device that generates an FM audio signal. , a mixing means for frequency division multiplexing a digital audio signal and an FM audio signal, a bias superimposition circuit, and a recording means.

The recording means records the output signal of the bias superimposition circuit in the deep part of the magnetic layer of the magnetic tape by using a rotary head for audio having a different azimuth angle from that of the rotary head for video.

A magnetic recording/reproducing apparatus of the present invention is a deep recording type magnetic recording/reproducing apparatus, which includes a reproducing means, first and second signal separating means, in addition to the same configuration as the magnetic recording apparatus described above.
a first demodulating means for demodulating a digital audio signal;
A second demodulating means for demodulating the audio signal is provided.

The digital audio signal generated by the action modulation means and subjected to multiphase DPSK modulation or offset polyphase DPSK modulation is frequency division multiplexed with the output audio signal of the FM modulation means, and is supplied to a bias superimposition circuit, where a high frequency bias is applied. The signal is superimposed.

The digital audio signal and FM audio signal on which the high-frequency bias signal is superimposed and taken out from the bias superimposition circuit are supplied to the audio rotary head by the recording means, thereby being recorded in the deep part of the magnetic layer of the magnetic tape. Ru.

In this way, polyphase DPSK or offset polyphase DPSK
Since the digital audio signal modulated by the frequency modulation and the FM audio signal frequency modulated are recorded together with the high frequency bias signal, linearity is improved.

Further, the audio signal reproduced by the reproducing means is separated into a digital audio signal and an FM audio signal by the first and second signal separating means, respectively, and the digital audio signal is demodulated by the first demodulation circuit, and The FM audio signal is demodulated in the second demodulation and modulation circuit.

Since the digital audio signal and the FM audio signal can be used separately in this way, a plurality of audio signals can be recorded and played back at the same time.

Embodiment FIG. 1 is a block system diagram showing an example of the apparatus of the present invention. In the figure, the portion above the dashed line A is a magnetic recording device (recording system), and the portion below A is a magnetic recording and reproducing device including a reproducing system.

To explain this embodiment, a standard color one-way color video signal is input to the terminal 25, and the video signal processing circuit 26 receives a standard color video signal.
is supplied to The video signal processing circuit 26 separates a luminance signal and a carrier color signal by known means, and frequency-modulates the carrier wave with this luminance signal to generate a frequency-varied wA luminance signal (F
M luminance signal) is generated, and the carrier color signal is low-band converted to generate a low-band converted carrier color signal, and these two signals are frequency division multiplexed to form a frequency spectrum as shown in FIG. 2(A). Output a signal. In FIG. 2(A), ■ is an FM luminance signal whose carrier frequency band is 5.4MH2 to 7.0MH2. OM
@z. (2) is a low-band conversion color carrier color signal, and its low-band conversion color subcarrier frequency is approximately 629kl-1z. The above video signal for recording is supplied to video rotary heads 28a and 28b via a recording amplifier 27. Further, the video signal processing circuit 26 supplies the standard color one-way color video signal to the synchronization signal separation circuit 29 as it is. The synchronization signal separation circuit 29 separates the vertical synchronization signal and connects it to the servo circuit 3, which will be described later.
Supply to 0.

Further, the left channel analog audio signal and the right channel analog audio signal inputted to the terminals 318 and 31b respectively are connected to the switching means 69a on the one hand.

Noise reduction (NR) circuit 70a via 69b
, 70b, and after the dynamic range is halved, it is sent to a pre-emphasis circuit 71a.

A pre-emphasis characteristic is provided at 71b, and signals above a predetermined level are cut at limiters 72a and 72b. The outputs of the limiters 72a and 72b are sent to FM modulators 73a and 73b, respectively, for example at 1.3MHz.
, is FM modulated with a 1.7 MHz carrier wave, and is sent to a mixer 75 after passing through bandpass filters 74a and 74b.

On the other hand, after unnecessary high-frequency components exceeding the audible frequency band are removed by low-pass filters 32a and 32b via switch means 69a and 69b, respectively, the sampling frequency is set to, for example, 47.952 kHz (=48 kHz÷1.
The data is supplied to A/D converters 34a and 34b via sample and hold circuits 33a and 33b of 001), where it is linearly quantized to 16 bits, encoded and sent to the PC.
M audio signal. This left and right channel PCM
The audio signal is supplied to an encoder 35.

The encoder 35 converts the even-numbered sample E-8 and the odd-numbered sample O8 in one field period into a
Error detection and correction codes P and Q are generated in the format shown in ).

In FIG. 3(A), data DATAI.

DATA2 is, for example, samples ES and O8 which have been subjected to time axis compression and interleaving, and each row of data DATA is in word units in the horizontal direction (one word is 8 bits).
1. A predetermined operation is performed on each 10 words of DATA2 (8 x 50 bits each) to generate 6 words of parity Q, and each row is 8 x 30 (-
8X6X5) Obtain the parity Q of the pit. The encoder 35 also encodes eight columns in the vertical direction, that is, one word in each row (
= 8 bits) data DATA1. A predetermined operation is performed every 32 words of DATA2° parity Q to generate 8×4 bit parity P for each column of 4 words.

Next, the above data DATA1. DATA2 and parity P, Q are divided into 36 words for 8 columns, and immediately before each of the 36 words, a synchronization signal 5YNC and an identification signal of 8 bits (=1 word) as shown in FIG. 3(B) are provided. ID,
Address signal AD[lR.

A block parity signal PARITY is added to form a data block of 40 words in total.

Synchronization signal 5YNC indicates the start of each data block. Address signal ADDR indicates the order of each data block in one track of digital audio signals (ie, 130 data blocks). Block parity signal PARI
TY is an error detection signal obtained by PARITY=IDΦADDR. Here, ■ is an addition operator modulo 2.

In the 130 data block of the data area shown in FIG. 3(C), the data D A T A1, DA shown in FIG. 3(A)
TA2 and parity P and Q are transmitted, but before that, 4
A preamble for clock recovery for data blocks is added followed by a postamble for two data blocks.

In this way, the encoder 35 generates a digital audio signal in the signal format of a total of 136 data blocks (=43.520 bits) shown in FIG. 3(C),
This is transmitted in one field period (=1159.94 seconds). Therefore, the transmission pit rate of the digital audio signal is 2.6086 (= 136x 320x59.
94) M bps.

Note that the encoder 35 is field synchronized with the video signal to be recorded by the output signal of the servo circuit 30.

The offset four-phase differential PSK modulator (OQDPSK modulator) 36 includes a conversion circuit that converts this digital audio signal into serial and parallel signals and outputs it alternately as two code strings, and a conversion circuit that converts these two code strings into 1/1 time slot of each other. A phase shift means for shifting by 2, and two code strings from this phase shift means are received as modulation signals, and the phases are 90" from each other at a predetermined frequency fc.
A known configuration consisting of a balanced modulation means that performs carrier suppression amplitude modulation on two different carrier waves separately, and a synthesis circuit that combines two amplitude modulated waves from the balanced modulation means and outputs a 0QDPSK modulated digital audio signal. It is said that

As an example, the carrier wave frequency t'c is selected to be about 3.0 MHz, which is 191 times the horizontal scanning frequency fH. Therefore, the frequency spectrum of the output digital audio signal of the 0QDPSK modulator 36 has a maximum level at the carrier frequency fc, and since the transmission pit rate is 2.6086 Mbps, the frequency spectrum of the digital audio signal output from the 0QDPSK modulator 36 is ±n×1. 30 MHz (= 2.6
086 MHz /2) becomes 0 at a distant frequency position,
This results in a well-known comb-like spectrum. However, the above n is a natural number.

Therefore, the output digital audio signal of the 0QDPSK modulator 36 is band-limited to remove unnecessary frequency components, and has a frequency of about 3.
The digital audio signal is passed through a bandpass filter 37 centered on MHz and whose passband width is selected to be about 0.7 times the transmission pit rate, and is band-limited to a digital audio signal with a frequency spectrum as shown by ■ in FIG. 2(B). After that, the signal is input to the mixer 75 via the terminal 38, frequency division multiplexed with the FM audio signal, and then supplied to the bias superimposition circuit 39, where it is superimposed with a high frequency bias signal.

The bias superimposition circuit 39 is a circuit that forms the main part of this embodiment,
For example, the configuration is as shown in FIG. 4 or FIG. 5.

4 and 5, the same constituent parts as in FIG. 1 are given the same reference numerals, and in FIG. 5, the same constituent parts as in FIG. 4 are given the same reference numerals.

The bias superimposition circuit 39 shown in FIG.
A high-frequency bias signal of, for example, 10.8 MH2 is superimposed, and this superimposed signal is passed through the recording amplifier 47 to the terminal 40.
Output to.

On the other hand, the bias superimposition circuit 39 shown in FIG.
The 0QDPSK modulated digital audio signal and the frequency modulated FM audio signal are sent to the coil 50.
After being taken out through a trap circuit consisting of a capacitor 51 and a bias oscillator 46, it is added and synthesized (superimposed) with a high frequency bias signal taken out from a bias oscillator 46 through a capacitor 52, and then outputted to a terminal 40.

The circuit shown in FIG. 5 has a well-known circuit configuration for bias recording, and the trap circuit prevents transmission of the high frequency bias signal to the recording amplifier 47 side, and the capacitor 52
This prevents the digital audio signal and FM audio signal from being transmitted to the bias oscillator 46 side. As the recording amplifier 47 of the bias superimposing circuit 39 shown in the fifth ffi, an inexpensive recording amplifier can be used as compared to the broadband, high-output, expensive recording amplifier required in the bias superimposing circuit 39 shown in FIG.

The above-mentioned superimposed signal taken out from the terminal 40 is supplied to the audio rotary heads 41a and 41b shown in FIG. 1, respectively.

The audio rotary heads 41a and 41b are attached to the rotating surface of a rotary cylinder (not shown) so as to face each other by 180 degrees, and are attached at a certain angle ahead of the mounting positions of the video rotary heads 28a and 28b. It is being Further, the azimuth angle of the audio rotating heads 41a and 41b is +30° for one and 130' for the other, and the azimuth angle of the rotating heads 28a and 28b for video is +6 for one.
'', and the other one is 16''.

The motor (not shown) that rotates the above rotating cylinder is
Based on the output signal of the servo circuit 30 to which the vertical synchronizing signal from the synchronizing signal separation circuit 29 is supplied, it rotates in phase synchronization with the vertical synchronizing signal.

As a result, the audio rotary heads 41a and 41b,
The digital audio signal and the FM audio signal are recorded with a high frequency bias into the deep part of the magnetic layer of the magnetic tape 43 that runs while being wound around the rotating cylinder over an angular range of more than 180'' to form an audio track, After that, a rotating video head 2 is placed on the surface layer of the magnetic layer on the audio track.
8a.

A recording video signal is recorded by 28b to form a video track.

At the same time, the control head 42 records control pulses generated from the vertical synchronization signal taken out from the servo circuit 30 by forming a control track along the longitudinal direction of the magnetic tape.

Next, the operation of the reproducing system for reproducing the magnetic chip 743 recorded by the above recording system will be explained.The rotary head 41a is read from the audio track formed in the deep layer of the magnetic layer of the recorded magnetic tape 43.

The modulated digital audio signal and the FMS voice signal alternately reproduced by 41b are supplied to a preamplifier 55. At the same time, video signals alternately reproduced from the video tracks of the magnetic tape 43 by the rotary heads 28a and 28b are supplied to the switching amplifier 56. Also, magnetic tape 4
3 control track to control head 42
The regenerated control pulse is supplied to the servo circuit 30. The servo circuit 30 controls the rotation of the rotary cylinder so that the reproduction control pulse is synchronized with the reference frequency signal.

The switching amplifier 56 is the rotary head 28a.

Each reproduced video signal 28b is amplified and switched to a continuous signal, and this signal is supplied to a video signal processing circuit 58 via a preamplifier 57.

The video signal processing circuit 58 separates and extracts the FM luminance signal and the low frequency converted carrier color signal from the reproduced signal by known means, performs FM demodulation to obtain the luminance signal, and obtains the carrier color signal by frequency conversion. The carrier color signal is superimposed on the luminance signal and outputted from the terminal 59 as a standard color one-way reproduced color video signal.

On the other hand, the preamplifier 55 is a rotary head 41a.

A reproduction equalizer 80 and a bandpass filter 8 amplify and switch the reproduced audio signal in which the digital audio signal and the FM audio signal from each of the FM audio signals are mixed and convert it into a continuous signal.
1a and 81b. Bandpass filters 81a, 81b
The output of is the limiter 82a.

82b is light, and the FM demodulators 83a and 83b respectively
M demodulated and de-emphasis circuit 84a.

After being given de-emphasis characteristics in 84b,
The dynamic range is restored by the noise reduction circuits 85a and 85b, and output as left channel and right channel audio signals from the output terminals 86a and 86b, respectively.

The regenerative equalizer 80 enhances the attenuated high-frequency components and then supplies them to the bandpass filter 60 . The reproduced modulated digital audio signal having the frequency spectrum shown in FIG. 2(B), which has been band-separated and extracted by the bandpass filter 60, is supplied to the 0QDPSK demodulator 61, where it is subjected to the known 0QDPSK demodulation and converted into a digital audio signal. The signal is supplied to a decoder 62.

The decoder 62 is supplied with a synchronization signal generated from pulses phase-synchronized with the rotation of the rotary cylinder from the servo circuit 30 in order to know the first reproduction position of the digital audio signal of each track. This decoder 62 performs processing such as error correction, 9 time axis corrections, 1 time axis expansion, and deinterleaving on the reproduced digital audio signal, and combines each zamble in the order of A/D conversion amount, and the left channel and a right channel digital audio signal.

After the digital audio signals of the left and right channels are converted into analog signals by D/A converters 63a and 63b, respectively, noise components generated during D/A conversion are removed by deglitcher circuits 64a and 64b, and then low-pass filters 65a, 65b
Unnecessary high-frequency components exceeding the audible frequency band are removed.

As a result, the left channel to the terminals 66a and 66b,
The right channel analog audio signal is output separately.

Next, the noise spectrum reduction effect according to the present invention will be explained. Approximately 3. OMH2±1.3M
0QDPSK modulated digital audio signal with Hz frequency spectrum■ and frequency modulated FM audio signal■
However, without superimposing a high-frequency bias signal, the sound is recorded directly into the deep part of the magnetic layer of the magnetic tape using a rotary head like in conventional equipment, and the video signal is recorded into the surface part of the magnetic layer. Reproduced modulated digital audio signal and F when a magnetic tape is reproduced with an audio rotary head
The frequency spectrum of the M audio signal is as shown in FIG. 7(A).

In FIG. 7(A), fSC is the color subcarrier frequency of the low-pass conversion carrier color signal, which is, for example, 629 kHz, and as shown by the broken line V, the low-pass conversion carrier color signal band has a frequency due to cross-modulation distortion. Since the noise spectrum exists at a large level and occurs in the low frequency region where the azimuth loss effect is reduced, it also occurs in the reproduced video signal of the video rotary head, degrading the color S/N. Furthermore, such cross-modulation distortion occurs due to the nonlinearity of the tape, and the resulting distortion degrades the error rate of the digital signal as described above, and increases the ratio of the carrier wave to the noise of the FM audio signal. It also deteriorates the C/N ratio.

On the other hand, in the frequency spectrum shown in Figure 6 above, 0
When a QDPSK modulated digital audio signal and an FM audio signal are recorded by superimposing a high frequency bias signal of, for example, 10.8 MHz according to the present invention, the frequency spectrum of the reproduced modulated digital audio signal is as shown in FIG. 7(B).
Experiments have shown that among the noise spectrum due to cross-modulation distortion in the low-pass conversion carrier color signal band surrounded by the broken line ■, the noise spectrum in the vicinity of the low-pass conversion color subcarrier frequency fsc is significantly reduced. confirmed by. Note that the high-frequency components in FIG. 7(B) are converted to the second
It is equalized to the spectrum shown in Figure (B).

Also, instead of 0QDPSK modulation, 4-phase differential PSK modulation (
Similarly, when a digital audio signal with a frequency spectrum similar to that shown in Figure 6 obtained by QDPSK modulation is directly deep recorded without superimposing a high frequency bias signal and then played back, the frequency spectrum is also low-frequency conversion. The noise spectrum near the color subcarrier frequency fsc is significantly reduced.

Therefore, the present invention can be applied not only to the 0QDPSK-modulated digital audio signal of the above embodiment, but also to the QDPSK-modulated digital audio signal.

In addition to the above-mentioned 0QDPSK and QDPSK modulation formats, the present invention also applies to 2-phase and 8-phase offset DPSK modulation and D
It can be similarly applied to PSK modulated digital audio signals. Also, to Example 9 - In the example, it was explained that the NTSC color video signal is recorded in the video track as a predetermined signal format.
The present invention is a deep recording method for recording PAL or S E CAM color video signals in a predetermined signal format.
The same applies to TR.

Effects of the Invention As described above, according to the present invention, a digital sound angle signal modulated by polyphase difference PSK or offset polyphase difference PSK is mixed with a modulated FM audio signal, and the deep part of the magnetic layer is mixed with a high frequency bias signal. Since the recording is made to be possible, it is possible to significantly reduce the noise spectrum in the reproduced signal that occurs in the low-pass conversion carrier color signal band due to cross-modulation distortion due to nonlinearity of the tape, and therefore the color S/
N can be improved, and the error rate of the reproduced digital audio signal can be improved, as well as the reproduced FM.
The S/N ratio of the audio signal can be improved, the compatibility characteristics of the magnetic tape can also be improved, and both FM audio and digital audio can be recorded and played back simultaneously, so two types of recorded tape software must be prepared. You can solve the problem of not having to do this.

Furthermore, FM audio and PCM audio can be used independently; TV audio can be used as FM audio, and compact disc (CD) can be used as PCM audio.

Digital audio tape (DAT) audio and F
It is now possible to simultaneously record the audio of M broadcasts, and in bilingual television broadcasting, for example, it is possible to record and play back foreign language audio for PCM audio and Japanese audio for FM audio with high sound quality. It has the following characteristics.

[Brief explanation of the drawing]

FIG. 1 is a block system diagram of one embodiment of the device of the present invention, and FIG.
The figure is a diagram showing an example of the frequency spectrum of the signal of each part of the block system illustrated in Figure 1, and Figure 3 is a signal format diagram for explaining the operation of the encoder in the block system illustrated in Figure 1.
4 and 5 are block system diagrams showing each bias superimposition circuit in the block system shown in FIG. 1, FIG. 6 is a diagram showing an example of the frequency spectrum of a signal recorded on an audio track, and FIG. (A) and (B) are diagrams showing a comparison of the frequency spectra of the reproduced signal when a 0QDPSK modulated digital audio signal is deeply recorded with a conventional device and the device of the present invention and reproduced. FIG. 2 is a block system diagram showing an example of a device. 25...Color video signal input terminal, 28a, 28b.
...Rotary head for video, 31a, 31b...Analog audio signal input terminal, 34a, 34b...A/D converter, 35...Encoder, 36...0QDPSK modulator, 39...Bias Heavy sleep circuit, 41a, 41b...
・Audio rotary head, 43...magnetic tape, 45...
Addition circuit, 46... Bias oscillator, 47... Recording amplifier, 50... Trap circuit coil, 51...
・Capacitor for trap circuit, 73a, 73b... Frequency modulator, 74a, 74b, 81 a, 81 b...
- Bandpass filter, 75...mixer, 80...regeneration equalizer, 83a. 83b... Demodulator (FM demodulator). -28= Procedural amendment January 11, 1989 Director General of the Japan Patent Office Yoshi 1) Takeshi Moon 1, Indication of the case 1988 Patent application No. 261319 2, Title of invention Magnetic recording device and magnetic recording reproducing device a Amendment Relationship with the case of a person who does 5-7-6 Kojimachi, Chiyoda-ku, Miyako
, the detailed description of the invention column of the specification to be amended, and the drawings. 7. Contents of the amendment (1) "Also, the terminals 31a and 31b are respectively..." stated from page 11, line 20 to page 12, line 14 of the specification.
The 1 input terminal 318.31b receives the left channel signal (1, +) and right channel signal (1, +) of the analog audio signal.
R+) is supplied to the input terminals 68a and 68b, and a left channel signal (
L2) and the right channel signal (R2) are supplied. If the movable contacts of the switch means 69a, 69b are both connected to the a side, the analog audio signals supplied to the input terminals 31a, 31b will be recorded as both FM audio signals and digital audio signals. On the other hand, if the movable contacts of the switch means 69a and 69b are both connected to the b side, the input terminal 31a. The analog audio signal supplied to 31b is also an FM audio signal and input terminal 68a. The analog audio signal supplied to 68b is recorded as a digital audio signal. Therefore, in the latter case, when recording a foreign language movie as a program source, for example, the stereo audio including the original foreign language is recorded as a digital audio signal, and the Japanese dubbed audio is recorded as an FM audio signal with high quality. be able to. Consider the case where both switch means 69a and 69b are connected to the b side. The left channel analog audio signal and the right channel analog audio signal input to the terminals 31a and 31b, respectively, are sent to noise reduction (NR) circuits 70a and 70.
0b and the dynamic range is halved, pre-emphasis characteristics are imparted to the signal by pre-emphasis circuits 71a and 71b, and signals above a predetermined level are cut by limiters 72a and 72b. The output of the limiters 72a, 72b is an FM modulator 73a. 73b, respectively, e.g. 1.3M)-1z,
The signal is FM modulated using a carrier wave of 1.7M1-12, and is sent to a mixer 75 after passing through bandpass filters 74a and 74b. Furthermore, the left channel analog signal and right channel audio signal input to each of the terminals 68a and 68b are corrected as follows. ■ "TV is available" written in lines 8 to 10 on page 27 of the statement [Also, in foreign language sources,
cM = It is possible to record and play back original stereo audio for voices and Japanese dubbed audio for FM audio with high sound quality.'' ■ Correct Figure 1 as shown in the attached sheet 3.

Claims (2)

[Claims] (1) An audio rotary head records an audio signal in the deep layer of the magnetic layer of the magnetic tape, and the audio signal is recorded on the surface layer of the magnetic layer above the audio track formed by the audio signal at a different azimuth angle from that of the audio rotary head. In a magnetic recording device that records a video signal by forming a video track using a rotary video head, the first modulating means generates a digital audio signal subjected to polyphase differential PSK modulation or offset polyphase differential PSK modulation; , a second modulating means for generating a frequency-modulated FM audio signal, and a mixing means for frequency division multiplexing the output digital audio signal of the first modulating means and the output FM audio signal of the second modulating means. a bias superimposition circuit that superimposes a high frequency bias signal on the output audio signal of the frequency division multiplexing mixing means; and a bias superimposition circuit that supplies the output signal of the bias superimposition circuit to the audio rotary head as the audio signal, and What is claimed is: 1. A magnetic recording device comprising: a recording means for recording data on a magnetic recording device; (2) An audio rotary head records an audio signal in the deep layer of the magnetic layer of the magnetic tape, and the audio signal is recorded on the surface layer of the magnetic layer above the audio track formed by the audio signal at a different azimuth angle from that of the audio rotary head. In a magnetic recording and reproducing device that forms a video track using a rotary video head that records a video signal, and reproduces the audio signal and video signal recorded on the magnetic tape, the magnetic recording and reproducing device uses polyphase differential PSK modulation or offset polygon modulation. a first modulation means for generating a digital audio signal subjected to phase difference PSK modulation; a second modulation means for generating a frequency modulated FM audio signal; an output digital audio signal of the first modulation means; a mixing means for frequency-division multiplexing the output FM audio signal of the second modulation means; a bias superimposition circuit for superimposing a high frequency bias on the output audio signal of the frequency-multiplexing mixing means; a recording means for supplying the audio signal to the audio rotary head and recording it in the deep part of the magnetic layer; a reproducing means for reproducing the signal recorded in the deep part of the magnetic layer; and a reproduction means for reproducing the signal recorded by the reproducing means. a first signal separation means for separating the digital audio signal; a second signal separation means for separating the FM audio signal from the signal reproduced by the reproduction means; and a signal separated by the first signal separation means. a first demodulating means for performing polyphase differential PSK demodulation or offset polyphase differential PSK demodulation of the digital audio signal; and a second demodulating means for demodulating the FM audio signal separated by the second signal separating means. A magnetic recording/reproducing device characterized by: