JPS59138178A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To attain complete tracking by obtaining a reference signal from a sound signal in reproducing recording information with azimuth recording. CONSTITUTION:A video signal Sv' and a synthesis signal between a modulating sound signal SAFM and a pilot signal SPILOT are recorded on recording tracks T1 and T2 overlappingly in different recording azimuth. On the other hand, heads HA1, HV1 and heads HA2, HV2 scan respectively recording tracks T1, T2, the synthesis signal between the modulating sound signal SAPM and the pilot signal SPILOT is reproduced from the heads HA1, HA2 and the video signal Sv' is reproduced from the heads HV1, HV2 at reproduction. Further, a time axis error due to tracking shift is detected from a signal SH' in frequency 3fH obtained from the sound signal SA' at reproduction is detected and tape running is controlled thereupon and tracking is attained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is directed to a magnetic recording medium for recording a video signal and an audio signal on a magnetic layer of a magnetic tape for so-called tilted azomass recording.
The present invention relates to a magnetic recording and reproducing device suitable for application to a TR (video tape recorder).

BACKGROUND ART AND PROBLEMS In a rotating head type VTR, a luminance signal YFM which is FM modulated on the high frequency side and a chroma signal CD which is converted to a low frequency band are synthesized, and the synthesized video signals are set at different azimuth angles from each other. Attempts have been made to use two different rotating magnetic heads to record on inclined tracks on a magnetic tape without placing guard bands.

This is the so-called inclined anomalous record.

In such a VTR, during playback, a recorded track must be accurately scanned with a corresponding magnetic head;
It is necessary to perform so-called tracking.

As a method to perform this tracking, a method has been considered that uses the horizontal synchronization signal (sync) of the video signal recorded at an angle, detects the time axis error due to track deviation, and performs tracking using this detection signal. For example, as shown in FIG. 1, assume that a track TA with a recording azimuth of θA by the head HA and a track TB with a recording azimuth of θB by the head HB are formed alternately. Assuming that the head salt and HB are shifted from the tracks TA and TB as shown in Figure 2, the horizontal synchronization signal H8ynC from the video signal played back from the recording track TB by the head HB is higher than that by the head HA than from the recording track TA. The horizontal synchronization signal H8sync from the video signal being played back can be obtained earlier in time.

Therefore, as shown in FIG. 2B, when the heads HA and HB are switched, the horizontal synchronization signal (sync interval expands and contracts (TS <'I'N <TL)), and a time axis error occurs due to rack misalignment. Therefore, tracking can be performed by detecting this and controlling, for example, tape running using the detected signal. What is shown in FIG. 2A is a switching control signal for heads HA and HB.

According to this method, it is theoretically possible to perform tracking, but generally the head H that records the video signal is
The azimuth angles of A and HB are relatively small, for example around ±7°, since increasing the azimuth angle will deteriorate the high-frequency characteristics, so the time axis error due to track misalignment will not be large, and based on this, It was difficult to track. That is, the diameter of the rotating drum is large, the number of scanning lines in one field is 262.5, and the horizontal period is 63.
5 μSec 1 When the azimuth angle is θ, the time axis error t [μ
sec) is as follows. Then, when θ=+7° and D=74.4,
t = TW X O, 12X 0.14
・・・・・・・・・・・・・・・(2) Even if the short track deviation is 10μm, t=0.15μ
sec, and the time axis error t does not appear large. A solid line a in FIG. 4 shows the relationship between the track deviation and the time axis error t when the azimuth angle θ is 7°.

By the way, the present applicant has previously developed a VT system in which a video signal and an audio signal are superimposed on the magnetic layer of a magnetic tape and recorded in a slanted azimuth manner, with the aim of obtaining an audio signal with an excellent S/N ratio.
I proposed R. In this method, for example, a video signal is recorded on the upper layer of the same magnetic layer of a magnetic tape, and an FM-modulated audio signal (modulated audio signal) is recorded on the lower layer using magnetic heads having different azimuth angles, and then reproduced. be. In this case, since the frequency of the modulated audio signal is lower than that of the video signal, the azimuth angle of the magnetic head for recording and reproducing this audio signal is relatively large, for example, ±45°.

In the above equation (1), if θ is set to 45°, and the track deviation ■ is 10 μm, t = 1.25 μ
sec, and the time axis error t appears relatively large.

The solid line in FIG. 4 shows the relationship between the track deviation field and the time axis error t when the azimuth angle θ is 456.

Therefore, if the modulated audio signal, that is, the recorded audio signal, contains a signal such as a horizontal synchronization signal (sync) of the video signal, tracking can be performed using the above-mentioned tracking method by using this signal. It becomes easier.

OBJECTS OF THE INVENTION The present invention has been made in view of the above-mentioned problems.In a magnetic recording and reproducing apparatus that performs azomass recording by superimposing a video signal and an audio signal on a magnetic layer of a magnetic tape, the audio signal and the reference signal are used during reproduction. This method was used to obtain the following information, and the tracking was performed based on this.

Summary of the Invention In order to achieve the above object, the present invention has first to fourth magnetic heads, the first to fourth magnetic heads have different azimuth angles, and the first and second magnetic heads have different azimuth angles. The gap width of the magnetic head is made wider than the gap width of the third and fourth magnetic heads, and the first and second magnetic heads record the magnetic tape in advance of the third and fourth magnetic heads, respectively. The first and third magnetic heads and the second and fourth magnetic heads are alternately switched and used for each unit period, and during recording, the first and second magnetic heads A recording audio signal is supplied to the head, a recording video signal is supplied to the third and fourth magnetic heads, and the recording audio signal and the recording video signal are superimposed on the magnetic tape. From above, the magnetic recording and reproducing apparatus is configured such that the first and second magnetic heads reproduce the recorded audio signal, and the third and fourth magnetic heads reproduce the recorded video signal, The recorded audio signal is converted into mfH (m
is an integer; The system detects errors and controls tape running based on the errors to perform tracking serve.

The present invention is constructed as described above, and the azimuth angle of the magnetic head for recording and reproducing the recorded audio signal can greatly reduce the time axis error due to the recording misalignment, so that tracking can be easily performed.

Embodiment Hereinafter, an embodiment of the present invention will be described with reference to FIG. 5 and subsequent figures.

In this example, as shown in FIG. 5, two rotating magnetic heads T (
VT and HV2 are installed with an angular spacing of approximately 180°, and two rotating magnetic heads HAI and HA2 are installed adjacent to the heads HVI and HV2 with an angular spacing of approximately 180°.
Mounted with angular spacing of °. Also, head HA
I and HA2 are rotated in the rotational direction
Mounted on the side. Further, (1) indicates a magnetic tape, which is run in the Y direction along a tape guide drum (2) obliquely over an angular range of approximately 180°. As shown in FIG. 6, the gap gV1 between heads Hv1 and HV2
The azimuth angles (inclination angles with respect to the direction perpendicular to the scanning direction X) θv1 and θv2 of and gV2 are set to be different from each other, for example, θV1#+7° and θv2≠−7°.

In addition, the gaps gA1 and g of heads HAI and HA2 are
The azomass angles θA1 and θA2 of A2 are made different from each other. In general, the crosstalk ratio due to anomous loss can be expressed as follows, where the crosstalk is C1 signal, 81, the recording wavelength is λ, the track width is W1, and the relative azimuth angle is 00. Gap gA1 between heads HAI and HA2
and azimuth angles θA1 and θA2 of gA2 are head H
Regarding the relationship between AI and HA2, HAI and T(vi, and HA2 and 'Hvz), for example, -θ in the above equation (3) is set to be 1 or more, and there is almost no crosstalk between each. For example, θA1
#-45''', θA2#+45°. Also, the angles 7'gA1 and gA of these heads HAI and HA2 are
2 is made wider than the widths of gaps gvx and gV2 of heads HVI and HV2. For example, head HVI
and the width of the gap gV1 and gV2 of HV2 is 0.3μ
In contrast, the widths of the gaps gA1 and gA2 between the heads HAI and HA2 are approximately 1.5 to 2.0 μm. Normally, in magnetic recording, it is possible to record on the magnetic layer of a magnetic tape to a depth that is approximately half the gap width of the magnetic head. Furthermore, when considering reproduction, the longer the recording wavelength, the deeper recording can be made in the magnetic layer.

The widths of the gaps gA1 and gA2 of the heads HAI and HA2 are defined as −\site Tl(vl and f(the gap ge of V2).
The reason why the width is wider than that of head 1 and gV2 is because the signals recorded by head) fvt and HV2 are wider than the width of head HAI and HA.
This is because the signals recorded in step 2 are recorded deeper into the magnetic layer of the magnetic tape.

Also, head Hv1* HV2 + HAI * HA
2 is rotated once in one frame, for example. and,
Head HAI, f(vl and head HA21 HV2
The magnetic tape (1) is scanned alternately for each field. At this time, heads HAI and HA2
scan the magnetic tape (1) in advance of the heads Hv1 and Hvz, respectively.

As will be described later, during recording, the heads HVI and T-Iv2
A video signal Sv' (a composite signal of a modulated luminance signal YFM and a low frequency conversion color signal CD, the frequency spectrum of which is shown in FIG. 7) is supplied to. In addition, the heads HAI and HA2 have a modulated audio signal sAFM N pilot signal 5.
A composite signal of PILOT (the frequency spectrum of which is shown in FIG. 7) and a high frequency bias signal 5BIAS is supplied. Therefore, as shown in FIG.
1) On top, the head HAI is placed alternately every field.
, recording track T1 and head HA2- by HVI K
Hvz recording tracks T2 are sequentially formed. In the recording tracks T1 and T2, the video signal Sv
', modulated audio signal SAFM and mother pilot signal 5P
The ILoT composite signal is recorded in an overlapping manner at different recording azimuths. That is, FIG. 9A shows head HAI and Hv.
t shows the recording track T1, but when observing this cross section, as shown in Figure B, first the head H
A composite signal of the modulated audio signal SAFM and the pilot signal Sp I LOT is recorded by AI to the lower layer of the magnetic layer (1a) of the magnetic chip f (1), and then the head HV
A video signal sv' is recorded on the upper layer of the magnetic layer (1a) by I. The same applies to track T2. In FIG. 9B, (1b) is the pace.

Also, during playback, head HAI + HVI and head HA2 # HV2 track recording tracks T1 and T, respectively.
2 is scanned. Therefore, heads HAI and HA2 reproduce a composite signal of the modulated audio signal SAFM and the pilot signal 5PILOT from the recording tracks T1 and T2, respectively. Furthermore, the recording tracks T1 and T2 and the video signal sv' are recorded in the heads Hv1 and HV2, respectively.
is played.

What is shown in FIG. 10 is the recording system and reproduction system circuits in this example.

In the figure, (100V) is a circuit for recording a video signal, and a video signal Sv is supplied to a terminal (II). This video signal Sv is supplied to a low noise filter a2 to obtain a luminance signal Y, which is supplied to an FM modulator (14) through a pre-emphasis circuit (13).

In the FM modulator 04, for example, the white peak is 4.
．． The luminance signal Y is FM-modulated so that the frequency is 8 MHz and the syn-edge lag is 3.5 MHz, and the modulated luminance signal YF is
M is obtained. This modulated luminance signal η is band-limited through a bypass filter f15), and is further band-limited through an amplifier (1e
After being amplified by , it is supplied to a combiner a7).

Still, the video signal Sv supplied to the terminal (II) K is supplied to the bandpass filter θ (to) to obtain the color signal C, which is supplied to the frequency converter (1, 1). A conversion signal is supplied from an oscillation circuit (21) to obtain a low frequency converted color signal CD with a carrier frequency of, for example, 688 KHz.This low frequency converted color signal CD is passed through a low frequency filter (21). The signal is band-limited and further supplied to an amplifier (after being amplified by 27J, a combiner 07).

A composite signal (hereinafter referred to as video signal Sv') of the modulated luminance signal YFM and the low-frequency conversion color signal cD obtained from the synthesizer 07) is passed through the changeover switch (c) and the rotary transformer (2).
It is supplied to head HVI through Yu, and also to head HV2 through selector switch (2) and rotary transformer (A). Selector switch (C) and (2) are connected to the R side during recording, and are connected to the R side during playback. Sometimes connected to the P side.

Further, in FIG. 10, (100A) is a circuit for recording an audio signal, and a terminal (to) K is supplied with an audio signal SA.

The audio signal SA is supplied from the terminal (to) to the sample hold circuit G3 through the compression circuit Gυ that constitutes the noise reduction circuit. In this sample hold circuit 0a, the audio signal sA is sampled at a frequency mfH (m is an integer, fH is a horizontal frequency).

In this example, a sampling signal SH with a frequency of 3fH is sent from the PLL circuit (Phase Lock Loo! circuit) (to).
is supplied and sampled at a frequency of 3fH. Incidentally, the video signal Sv is supplied as a reference signal to the horizontal synchronization signal T (sync is the PLL circuit C33) separated by the synchronization separation circuit cla.

The audio signal S8' sampled by the sample and hold circuit L3 is supplied to the FM modulator (c). and,
In this FM modulator (51), the audio signal SA' is FM-modulated, for example, with a carrier frequency of 1 MHz, to obtain a modulated audio signal SAFM (the frequency spectrum is shown in FIG. 7). The audio signal SAFM is supplied to a synthesizer 07) through a loaf filter or a band pass filter (7) for removing harmonics.

In addition, (to) is the high frequency bias signal 5BIAS for recording.
This is an oscillator to obtain . From this oscillator (to), 5
An oscillation signal of approximately 15 MHz is obtained, and this is supplied to the synthesizer G7) as a noisy signal SB IAS.

To (to) is the pilot signal 5PI for jitter correction
This is an oscillator for obtaining LOT. From this oscillator, an oscillation signal with a frequency close to the carrier wave number of the modulated audio signal SAFM, for example 1.7 MHz, is obtained.
The signal 8PILOT is supplied to the synthesizer 07) as a pilot signal 8PILOT.

In the synthesizer 0η, the modulated audio signal SAFM, the bias signal 5BIAS, and the pilot signal 8PILOT are combined. After this composite signal is amplified by an amplifier (4 (1), it is supplied to the head IAI through a changeover switch (4I) and a rotary transformer (4), and this composite signal is passed through a changeover switch (tA3) and a rotary transformer (t44) to the head IAI. The changeover switch (4I) and 1, 1:l are respectively set to R during recording.
When playing, it is connected to the P side.

When recording, switch (c), (25), (4
Since IJ and (43) are respectively switched to the R side, the heads HVI and HV2 receive the video signal Sv as described above.
′ is supplied.

In addition, the heads HAI and HA2 have a modulated audio signal SAF.
A composite signal of M, a pilot signal 5PILOT, and a high frequency bias signal 5BIAS is supplied. Therefore, as shown in FIG. 9, recording tracks T1 by the heads HAI I HVI and recording tracks T2 by the heads HA2 and HV2 are sequentially formed alternately for each field on the magnetic tape (1).

Further, in FIG. 10, (200V) is a video signal reproduction system circuit. As described above, the video signal ~' reproduced from the recording track T1 and the head Hv1 is supplied to the switch circuit 6υ through the amplifier (501).

As mentioned above, the head HV2 is moved from the recording track T2.
The reproduced video signal Sv' is supplied to the switch circuit 6υ through an amplifier (502). switch circuit 6
For υ, head HVI and Hv2 are connected from terminal (5・La).
A switching control signal SC obtained in accordance with the rotational position of is supplied, and the switching is controlled. From this switch circuit 61), the head HVI and the video signal Sv' reproduced in (v2) are obtained alternately for each field.

The video signal Sv' obtained from this switch circuit 6υ is HINO! This is supplied to Sfiltalo 2, and this) I/4'
A modulated luminance signal YFM is obtained from the filter. This modulated luminance signal YFM n') is supplied to the FMQ [device f54] through the transmitter circuit 64, and is supplied to the FM demodulator 64.
A brightness signal Y is obtained. This luminance signal Y is supplied to a synthesizer 66) through a de-emphasis circuit 6ω.

Also, the video signal SV′ obtained from the switch circuit 6υ
Is it low pass filter 6? ), and a low frequency converted color signal CD is obtained from this low mother filter η.

This low frequency conversion color signal CD is supplied to a frequency converter (5 rods). This frequency converter 6υ is supplied with conversion signals from an AFC and APC circuit (automatic frequency and automatic phase control circuit) (5I). The low frequency converted color signal CD is converted into a color signal C having a carrier frequency of, for example, 3.58 MHz.

This color signal C is supplied to a synthesizer (a) through a bandpass filter (60).

In the synthesizer, the luminance signal Y and the color signal C are synthesized, and a video signal Sv is obtained at the output terminal 6υ.

Further, in FIG. 10, (200A) is a circuit for reproducing audio signals. As mentioned above, the composite signal of the modulated audio signal SAFM and the pilot signal 8PILOT reproduced by the head HAI from the recording track T1 is sent to the amplifier (701).
) is supplied to a pantone R filter (711) whose center frequency is approximately IMHz. A modulated audio signal SAFM is obtained from the bandpass filter (711),
This is transmitted through the limiter circuit (721) to the FM retoucher (7).
31). An audio signal SA' is obtained from this FM tuner (731), and this is the switch circuit ff4]
is supplied to the A side terminal of.

In addition, as described above, from the recording track T2, the head HA
A composite signal of the modulated audio signal SAFM reproduced in step 2 and the pilot signal 5PILOT is supplied through an amplifier (702) to a bandpass filter (712) whose center frequency is approximately I MHz. Band Gus Filter (
A modulated audio signal SAFM is obtained from the FM demodulator (732) via a limiter circuit (722).
supplied to An audio signal SA' is obtained from this FMi modulator (732), and is supplied to the B-side terminal of the switch circuit σ.

The switch circuit 64) is connected to the head H from the terminal (74a).
A switching control signal SCA obtained according to the rotational positions of AI and HA2 is supplied to control the switching.

That is, during one field period when the head HAI scans the recording track T1, the terminal is switched to the A side, and the head H
During the other one field period when A2 is scanning the recording track T2, the terminal is switched to the B side.

Therefore, from this switch circuit 64), the FM demodulator (
Single sound signal SA' obtained from (731) and (732)
are obtained alternately for each field. This audio signal SA
' is supplied to the Ronox filter σQ and the audio signal SA
is obtained, which is supplied to the combiner σe.

In addition, the composite signal reproduced by the head IAI is sent to the amplifier (7
01) to the switch circuit 6η.

In addition, the composite signal reproduced by head HA2 is sent to an amplifier (7).
A switching control signal SCA is also supplied from a terminal (77a) to this switch circuit Vη to control its switching.Therefore, from this switch circuit 6′? , head HAI and HA
The composite signals reproduced in step 2 are obtained alternately for each field. This composite signal is supplied to a bandpass filter a81 whose center frequency is approximately 1.7 MHz, and a pilot signal 5PILOT is obtained from this bandpass filter σ group. This mother pilot signal 5PILσ is supplied to the FM demodulator through the limiter circuit, and the notter detection signal SJT is obtained from this FM demodulator (80). After this jitter detection signal SJI is inverted by the inverter (8I), It is supplied to the synthesizer iB through a semi-fixed resistor [F] for level adjustment.

In the synthesizer f76), the low ? A signal corresponding to the jitter detection signal SJr is subtracted from the audio signal SA supplied from the switch circuit, thereby canceling out the jitter component contained in the audio signal sA. Therefore, this synthesizer fff9
The audio signal sA from which the noise component has been removed is returned, and this is supplied to an output terminal (84) through an expander (8 moats) constituting a noise reduction circuit.

Also, the audio signal SA' obtained from the switch circuit a4)
is supplied to the limiter circuit, and a signal SH' with a frequency of 3 fH is obtained from this limiter circuit.
H' is normally obtained at a constant period, but if the heads HAI and HA2 are out of track with respect to the tracks T1 and T2, the period expands or contracts in accordance with the switching point of the heads HAI and HA2. . For example, if heads HA 1 and HA2 are out of track with respect to tracks T1 and T2 as shown in FIG. 11, then as shown in FIG. Correspondingly, the period tL is slightly longer than the normal period tN, and t corresponds to the switching from head HA2 to HAI.
The period tB is a little shorter than N. In this case, since the azimuth angles θA□ and θA2 of the head HAI I HA2 are each as large as ±45°, a relatively large time axis error due to this track deviation can be obtained. Incidentally, FIG. 12A shows the switching control signal SCA.

This signal SH' is supplied to the mono multivibrator (9υ), and from this mono multivibrator (9υ)
As shown in Figure 2C, for example, from the rising edge of the signal SH'
A pulse signal P1 having a /'P pulse width of h is obtained, and this is supplied to the mono multivibrator (9-side).

This mono multivibrator (from 9th onwards, as shown in Figure 12, from the falling edge of the pulse signal P1 to t2
A pulse signal P2 having a pulse width of is obtained and is supplied to the trapezoidal wave generation circuit 03. From this trapezoidal waveform generating circuit, as shown in FIG.
A trapezoidal wave signal 5TRP having a predetermined slope from the rising edge to the falling edge of FIG.
). A signal SH' is supplied to this sample and hold circuit, and the trapezoidal wave signal 5TRP is sampled and held at the rising edge of the signal SH', for example. Therefore, this sample and hold circuit ((b)
, a hold signal 5HOL as shown in FIG.
D is obtained. In this hold signal 5HOLD, a signal Se corresponding to a deviation of the period of the signal SH' from the normal value, that is, a time axis error, appears. This hold signal 5F (OLD) is supplied to the dart circuit (E). The switching control signal SCA is supplied to this date circuit (951) from the terminal (95a), and as shown by the solid line in FIG. (One of the signals Se appearing on OLD is inverted to obtain a rectified signal. Here, the rectification is performed because the error signal Se is sent from head HAI to HA2, HA
From 2 to HAI switching, the phase is reversed, but the track T
This is because the directions of the deviations for T1 and T2 are the same. This rectified signal is supplied to a hold circuit (a) and held as shown by the broken line in FIG. The cazostan motor (mark 9 is controlled to control the tape travel, and the head H
Tracking servo is applied so that AI and I(A2, and by extension heads HVI and HV2) correctly scan the tracks T1 and T2.

This example is configured like this, and the video signal S is connected to the terminal (1υ).
During recording when the audio signal SA is supplied to the v1 terminal (to), the video signal Sv' is supplied to the heads Hv1 and Hv2, and the heads HAI and HA2 receive the modulated audio signal SAFM, the pilot signal 5PILOT, and the high frequency bias signal 5BIAS. A composite signal of Therefore, as shown in FIG. 9, recording tracks T1 by heads HAI and HVI K and recording tracks T2 by heads HA2*'HV2 are sequentially formed on the magnetic tape (1) alternately for each field. . Then, on the recording tracks T□ and T2, the video signal Sv', the composite signal of the modulated audio signal SAFM and the pilot signal 8PILOT are superimposed and recorded with different recording anomalous values.

Furthermore, during playback, heads HAI I HVI and heads HA2 and HV2 move to recording tracks T1 and T2, respectively.
scan. Then, the heads HAI and HA2 reproduce the composite signal of the modulated audio signal SAFM and the pilot signal sp I LOT on the recording tracks T1 and T2. Further, the heads HV1 and HV2 reproduce the re-video signal Sv' from the recording tracks T1 and T2, respectively.

Therefore, the video signal Sv is obtained at the output terminal [F]υ, and the audio signal sA from which the jitter component has been removed is obtained at the output terminal □□□.

During playback, a time axis error due to track misalignment is detected from the 3fH frequency signal SH' obtained from the audio signal SA', and tape running is controlled based on this.
Tracking is taken.

According to this example, the azomass angles θA1 and θA of the heads IAI and HA2 that record and reproduce the modulated audio signal SAFM are
2 is large, and since a large time axis error due to track deviation can be obtained, tracking can be easily achieved.

Further, the video signal Sv' and the modulated audio signal SAFM are recorded on the magnetic layer (1a) of the magnetic tape (1) using separate heads at different recording azimuths, and are then reproduced. Therefore, the recording and reproducing of each signal hardly affects the recording and reproducing of other signals.

Therefore, it is possible to record the modulated audio signal SAFM without limiting the band and level, and it is possible to make the S of the audio signal SA excellent.

In the above embodiment, the sampling signal sH has a frequency of 3rH, but as described above, this signal sH has a frequency of mfH (m is an integer, fH is a horizontal frequency).
can be used. Among them,
Frequencies of 2fH and 3fH are suitable. Note that when using the fH frequency, it is conceivable to sample only the beginning of each track due to the band of the audio signal.

Further, in the above-described embodiment, the tape running is controlled by controlling the capstan motor, but it is also conceivable to control the reel motor.

Effects of the Invention According to the present invention described above, the recorded audio signal is a signal obtained by sampling the audio signal at a frequency of mfH and then FM modulating it, and during reproduction, the mfH in the reproduced recorded audio signal is
ci') Detects the frequency component, obtains the time axis error due to track misalignment from this detection signal, controls chive travel based on this, and uses a tracking sensor to record and reproduce the recorded audio signal. The azimuth angle of the magnetic head can be made larger than the azimuth angle of the magnetic head that records and reproduces recorded video signals due to its recording frequency band, and it is possible to obtain a large time axis error due to track misalignment, making it easy to track. I can do it.

[Brief explanation of the drawing]

Figures 1 to 4 are diagrams for explaining an example of a tracking method, Figure 5 is a diagram showing a rotary head device in an embodiment of the present invention, and Figure 6 is a gap in the rotary head. 7 is a diagram showing the frequency spectrum of the recording signal, FIG. 8 is a diagram showing the recording pattern on the magnetic tape, and FIG. 9 is used to explain the recording state on the magnetic tape. 10 is a circuit configuration diagram of an embodiment of the present invention, and FIGS. 11 and 12 are diagrams for explaining the example in FIG. 10, respectively. (1) is a magnetic tape, (2) is a tape guide drum, C3
2 is a sample hold circuit, 6 is an FM modulator, (73
t) and (732) are the F'M demodulators, respectively, the limiter circuit, (to) the servo circuit, (991 is the cab stan motor, and (100A) and (100V) are the audio signal and video signal recording systems, respectively. circuit, (20OA) and (20
0V) are audio signal and video signal playback circuits, respectively.
HAI t HA2 r )fvt and HV2 are rotating magnetic heads, respectively. Fig. 1 Scanning direction Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7

Claims (1)

[Claims] The first to fourth magnetic heads have different azomass angles, and the gap width of the first and second magnetic heads is different from that of the third and fourth magnetic heads. The gap width is made wider than the gap width of the magnetic head, and the first and second magnetic heads scan the magnetic tape before the third and fourth magnetic heads, and the first and second magnetic heads scan the magnetic tape before the third and fourth magnetic heads. The magnetic head M2 and the fourth magnetic head are used while being switched alternately every unit period, and during recording, a recorded audio signal is supplied to the first and second magnetic heads, and the third and fourth magnetic heads are used. A recording video signal is supplied to the magnetic head No. 4, and the recording audio signal and recording video signal are superimposed and recorded on the magnetic tape, and during reproduction, the recording is performed by the first and second magnetic heads from above the magnetic tape. In the magnetic recording and reproducing apparatus, the recording video signal is reproduced by the third and fourth magnetic heads at the same time as the audio signal is reproduced. , fH is the horizontal frequency), and is then FM modulated. During playback, the mfH frequency component in the recorded audio signal is detected, and this detected signal is used to detect time axis errors due to track shift. 1. A magnetic recording/reproducing device characterized in that the tape running is controlled based on the magnetic field and the magnetic field, and a tracking sensor is performed.