JPS6063709A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To make a rotary magnetic head trace a track appointed by a control signal even when hysteresis, etc., occur in an electricity-mechanism converting element, by suppling an added signal of a sampling-hold signal and its control signal to the element to which each rotary head is fitted while each magnetic head does not contact with a magnetic tape. CONSTITUTION:The output signal of an error detecting circuit 35 is supplied to an adder circuit 38 and the output signal of the adder circuit 38 is supplied to latch circuits 39a and 39b, respectively. The latch circuits 39a and 39b successively and alternately latch with a latch signal obtained immediately after the error detecting circuit 35 outputs a signal corresponding to the number of error tracks after obtaining a reproducing vertical synchronizing signal supplied to the latch signal input terminals 39La and 39Lb of the latch circuits 39a and 39b. The output signal of each latch circuit 39a and 39b is supplied to DA converters 40a and 40b which convert digital signals into analog signals, respectively, and, at the time, the output signals of the latch circuits 39a and 39b are respectively connected with one and the other fixed contacts of a switching circuit 41. Then a signal obtained at the movable contact of the circuit 41 is supplied to the adder circuit 38.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic recording and reproducing apparatus capable of reproducing tape at tape speeds other than normal speed, such as slow mode and high speed mode.

BACKGROUND TECHNOLOGY AND PROBLEMS A magnetic recording/reproducing device (hereinafter referred to as VTR) uses a plurality of rotating magnetic heads (hereinafter simply referred to as heads), for example, two rotating magnetic heads (hereinafter simply referred to as heads).
are attached to the rotating drum or rotating plate at equal angular intervals (1800 in this case), and record signals alternately on the magnetic tape as the rotating drum rotates,
Alternatively, it is common to alternately reproduce signals from magnetic tape.

By the way, in order to accurately trace (scan) these heads to the recording track during playback, these heads are attached to a rotating drum via an electro-mechanical conversion element such as a bimorph plate (hereinafter referred to as a bimorph plate). It has been proposed to drive (shift) the electrodes attached to both sides of the bimorph plate by supplying a drive signal to the electrodes attached to both sides of the bimorph plate during playback, so that the head automatically traces the recording track. There is.

To explain this with respect to FIGS. 1 to 4, (1) shows the substrate, (2) shows the entire rotating magnetic head device (rotating drum), (3) shows the upper drum, and (4) shows the lower drum. ,
(5) is a drive mechanism such as a motor. In this example, the lower drum (4) is fixed on the substrate (1), and only the upper drum (3) rotates. (6a) and (6b) are a pair of heads (rotating magnetic heads),
They are attached to the upper drum (3) via bimorph plates (7a) and (7b), respectively. Of course, the angular spacing between the two in this case is chosen to be 180°. In addition, (8) is a tape guide attached to or formed on the lower drum (4), and (9)
) a control (CTL), f system magnetic head, a
@ indicates magnetic tape, 18 to rotating drum (2)
It is arranged to be transported in a state where it is wrapped over a slightly larger angular range than o0. Therefore, the angle θl shown in FIG. 1 is the contact area of the heads (6a) (6b) with respect to the magnetic tape, and the angle θ2 is the non-contact area.

FIG. 3 shows the recording tracks of the magnetic tape QO), where it is assumed that the track (ha) is recorded by the head (6a) and the track (llb) is recorded by the head (6b). Pct indicates CTL pulse.

In such a device, the head 6a) (6
1) Detects the positional deviation of the trace with respect to the tracks (lla) and (llb), and supplies a corresponding drive signal to the bimorph plates (7a) (7b), thereby driving the heads (6a) and (6b). The height of the upper drum (3)
By changing the head mounting surface (height of the head), the rotating magnetic head can almost accurately place the tape on the tape, not only in the normal playback mode, but also in other random playback modes, that is, at various speeds. recording track (tia
) and (llbl) can be traced, and therefore a reproduced image without guard band noise can be obtained.

In this case, the signals supplied to the bimorph plates (7a) and (7b) are preset by the transport speed (tape speed) of the magnetic tape 00), information signals from CTL pulses, etc. 6a) or (6b
) is reproducing the signal from the track (lla) or (llb), the drive signal to the bimorph plate (7a) or (7b) is controlled to an appropriate value by the feed mask signal in a closed loop. (6a) or (6
In the non-contact section with the chi 7' (10) in b), the bimorph plate is driven only by the information signal, and the head (
6a) or (6b) is the track (Ila) or (iib
) has the disadvantage that a large tracing error tends to occur at the initial position of tracing.

To explain this state, for example, when playing back a still image, in still playback, the heads (6a) and (6b)
For example, the trajectory u21 shown by the dotted line in FIG. , Nitan,
Since Rika is located at 1l-nfia, right hand 6 and μfh are included,
If this continues, noise will occur. Therefore, in this case,
Looking only at the head (6a), as shown in FIG. 4A, the height of the head (6a) is changed over time by supplying the tilt signal So to the bimorph plate (7a),
This operation is carried out in the chive contact section θ1 of the head (6a).
By repeating this every time, the head (6a) can accurately trace the track (lla) or (ub). In FIGS. 4A and 4B, time is plotted on the horizontal axis, in FIG. 4A the voltage of the drive signal of the bimorph plate (7a) is plotted on the vertical axis, and in FIG. The amount of deviation of the tip (more precisely, the amount of deviation of the height of the head (6a)) δ is taken and shown. And in this case ■o is the third
It is given corresponding to the deviation amount δ0 indicated by the arrow in the figure. In FIG. 4, τ1 and τ2 each indicate one field period, τ1 is the reproduction period of the head (6a), τ2 is the flyback period of the head (6a), and τ3 is the reproduction period of the head (6b). (-τ1+τ2) is one rotation period of the rotating drum (2). The head (6b) may perform the same operation as described above with a period delayed by one field.

The above description has been given for the case of still mode, but even for cases other than the normal speed of the magnetic tape such as slow mode and high speed mode, the slope signal So corresponding to the tape speed can be applied to the bimorph plates (7a) and (7b), respectively. supply. By the way, taking the slow mode as an example, it is possible to make the heads trace in accordance with the tracks by supplying the slope signal So to the bimorph board as described above, but it is possible to make the heads trace in accordance with the tracks. It is unavoidable that mistracking at the starting point will occur.

To avoid such drawbacks, at the point when a certain head finishes tracing with the magnetic tape, the position (height) that the head should trace next time is detected, that is, the prediction is obtained, and the head By supplying the expected voltage to the bimorph plate of the head during the non-contact period with the tape,
A system as shown in FIG. 5 has been proposed that prevents mistracking from occurring at the beginning of the next trace when the head traces the next time.

This FIG. 5 will be explained. The CTL signal Pct from the CTL head (9) is suitably amplified by an amplifier (131) and supplied to the load terminal of an up-down counter o4 (this is the first up-down counter).
The TR capstan (not shown) is equipped with a frequency generator (F
G) t151 is installed, and the signal (noyasis) ~ from this is amplified by the amplifier (16) and sent to the counter (
141 is supplied to the clock signal input terminal. Naoko) F
G (15), 1: The frequency of Renohass corresponds to the tape speed, and this is not necessarily obtained only from the signal from F G (15).

Furthermore, a switching pulse Px (shown in FIG. 6C) having a frequency of generally 301-1z is formed by the PG pulse obtained in response to the rotation of the drum (2), and this switching pulse PX and phase or 1800
A different switching system Py is an input terminal (17a)
and (17b) K is supplied, and the input terminal (17a) K
The supplied . and cis is 60 in the frequency doubling circuit αQ.
Pulses with a repetition frequency of 1-1z (Figure 6D)
This is supplied to the load terminal of the second up/down counter (19), and the Noxis supplied from FG (151) is similarly fed to the frequency doubling circuit (20).
The repetition frequency of the pulse obtained at G (151) is doubled, and this is supplied to the clock terminal of the up/down counter mentioned above, and when there is a load input to the second counter (11), The counters for outputs f and g2 are stored as input data (1'l), and the second counter a9 calculates the stored count value and the cyclic motherboard number (the number of pulses from the double multiplier circuit). It is designed to count.In addition, 0D is the magnetic coefficient f.
This is an up/down command signal input terminal to which an addition command signal or a subtraction command signal is supplied based on the forward and reverse signals of α.

The output of this second counter α9 is digital-analog (
1)-A) The converter (2) is supplied, and its output is supplied to the tube 1 and the second sampling and hold circuits (23a) and (23b). Furthermore, the terminals (17a) and □
(17b) Switching signals Px and Py supplied to
are the first and second delay circuits (24a) and (24b), respectively.
), in which pulses Pi and Pj corresponding to the end of the reproducing period of the heads (6a) and (6b) are obtained as shown in FIGS. 6I and J, respectively. The output from the DA converter (2) is sampled and held at the time of generation of these pulses. (25a) and (25b)
) adds the sampled signal in this manner and the slope signal so corresponding to the tape speed supplied to the drive signal input terminals (26a) and (26b), and sends the respective summed outputs to the piezo-roof plate (7a). ) and (7b) are adders that supply K. Note that these delay circuits (24a) and (24
b) The delay time due to each switching signal PX and Py
Each field is a little less than one field from the start-up time of the head (6a).
)'s bimorph plate (7a) samples the sampling hold circuit (23a) attached to K. Each of these sampling bold circuits (23a) and (23b) holds approximately one field.

In the circuit shown in FIG. 5, the pulse from FG (f51) is doubled by the frequency doubling circuit (a) and supplied to the 20th count α9,
It is also possible to set in advance so that the frequency of the pulse obtained above 1 is the frequency supplied to the clock signal input terminal of the second counter H, in which case the frequency 2
The multiplier circuit (A) is no longer necessary and supplies the pulses from FGQ51 directly or through an amplifier as necessary to the second counter a9, and steps down the frequency of the pulses from FGQ151 to IA. Even if the clock signal is supplied to the clock signal input terminal of the first counter α, the same effect as described above is achieved.

Next, the operation of the above-described configuration will be explained using FIG. 6.

The first counter I counts FG (pulses obtained in connection with the rotation of the capstan) with respect to CT L /# 151, and this CT
For example, there are 1024 no(sys) in one cycle, that is, in one frame of the video signal, for L/#rus Pcsis.

This number of pulses within one frame is independent of Ziegesby F. A signal S5 obtained by digital-to-analog conversion of the output signal of the first counter Q4) is shown in FIG. 6E, but in FIG. 6, the stepped portion is shown as a straight line. Next, if we consider only the second counter aCJ (i.e., consider the output of the first counter (141 and so on as 0)), it will be reset every pulse Pz (see the 6th diagram), so In the above state, the sixth
A signal s6 shown in Figure G is obtained. This signal s
6, the clock signal input to the counter is twice as large as the signal s5, so the slope is twice that of the signal s5.

By the way, this second counter aCJ is supplied with the signal S5 from the first counter I, and the second counter α
Since the pulse Pz is supplied from the load terminal doubler circuit α mark of 9, the output (count) of the first counter 0 (a) is used as the base and the count value is added. As a result, a signal having the waveform shown in FIG. 6GK is obtained at the output terminal of the second counter α9. Note that this example shows a case where the speed is three times that in the normal state, and therefore, the track to be traced by head control 6a) and (6b) is the same in the period To shown in FIG. Track A in Figure 6A.

If so, the period T1 e T2 + T3...
...then Truck AI + A3! A4...
...becomes.

In this FIG. 5, as shown in FIG. 6, the 20th counter a9, which uses the output value of the first counter a4 as a pace at the rising time t1 of a certain switching pulse Px, further increases the output value at the rising time t3 of the next pulse Pz. This indicates a value equal to the output value of the first counter α(a) at time t5 of the next pulse Pz (the same applies to the switching pulse Py). That is, the second counter 09 determines the position of the track to be traced when the heads (6a) (6b) start tracing by switching pulses Px, P.
The prediction is made half a period in advance of y. Zangling hold circuits (23a) (23b) are connected to this second counter α.
Sampling the predicted value of 9, head (6a) (6
This predicted value will be held until the end of the trace in b).

As explained above, according to this FIG. By sampling and holding the pulse Pj signal S6 at almost the final point of the trace, it is possible to detect the height of each head above the reference position at the start point of the next trace. During the flyback period of each head, the signals are supplied to the bimorph plates (7a) and (7b) to which each head is attached, so each head can be brought to an appropriate trace start position without any difficulty. It has the feature of being able to be placed on the ground, allowing for ample height correction.

However, in such a magnetic recording and reproducing device, when hysteresis occurs in the bimorph plates (7a) (7b), the heads (6a) (6b) may not trace the track designated by the control signal, and good reproduction may not be possible. In some cases, this may cause an inconvenience in that an image cannot be obtained.

Purpose of the Invention In view of the above, the present invention provides a bimorph plate (7a) as described above.
Even if hysteresis occurs in (7b), the head (6a)
(6b) is intended to trace the track designated by the control signal.

SUMMARY OF THE INVENTION The present invention includes a plurality of rotating magnetic heads attached to an electro-mechanical transducer, and a control voltage applied to the electro-mechanical transducer to shift the rotating magnetic heads in a direction across tracks of a magnetic tape. In a magnetic recording and reproducing apparatus configured as shown in FIG.
n(n
is a positive integer excluding i'l) is counted every time each rotating magnetic head switches to the reproduction state to obtain a second counting output, and this first counting output is used as a pace. The count output obtained by adding (or subtracting) this second count is sampled and held at the end of the reproduction period of each rotating magnetic head, and a reference field time is formed so that the first and second count outputs are obtained. A control signal 1δ corresponding to the number of error tracks is generated by comparing the reference field time and the reproduced field time, and the sum signal of this sampled and held signal and this control signal is applied to the non-paired signal of each rotating magnetic head with respect to the magnetic tape. According to the present invention, even if hysteresis or the like occurs in the electro-mechanical transducer, the rotating magnetic head does not receive the control signal. You can trace the specified track.

Embodiment Hereinafter, one embodiment of the magnetic recording/reproducing apparatus of the present invention will be described with reference to FIGS. 7 and 8. In FIG. 7, parts corresponding to those in FIG. 5 are designated by the same reference numerals, and detailed explanation thereof will be omitted.

In this example, in addition to the example in FIG. 5, the reference field time (of the designated track) corresponding to the track designated by the second counter 0 (a) is determined from the output signals of the first and second counters a4 and α9. address).

That is, this first counter 041 and the 20th counter 0!
Considering J again, if the output value of the secondary counter aa aa jumps from the maximum value to the minimum value or from the minimum value to the maximum value, it means that the track specified by the counter (141 (11) is updated by one track. Counter Q
4) The count value of H jumps from the maximum value to the minimum value during playback in the forward direction; in this case, track An
is updated to track An+1, and the change from the minimum value to the maximum value occurs during reproduction in the reverse direction, and in this case, it means that track An has been updated by track An-tK. Therefore, by counting the number of times the output value of counter Q4)(11 jumps, the counter (+4
It is possible to know the relative number of changes to the track specified by 1α Yu.

For example, in the case of the triple-speed high-speed search shown in FIG. 6, if the track to be traced during period To is track AO, then period 'r1. 'r2. The tracks to be traced to 'r3... are each track Al + A3 r A4
It becomes... This can be seen by counting the number of jumps in the output value of the first counter (tl), but it can also be seen by counting the number of jumps in the output value of the second counter (tl).

In this example in FIG. 6, track A3 is traced during period T2.
is known from the number of jumps of the output value of the first counter (141) and the second counter θ■ in the period To at the time tQ, and the track A4 traced in the period T3 is 1. counter a
The number of jumps (llol) of the output value of the first counter I in the track AO indicated in (a) and the period TO
This can be determined from the number of times (3 times) of the output value of the second counter (11) in period Tj.
The track number XO1 indicated by the output value of the first counter (14) at the edge dimension ti of i, the first
The number of times the output value of the counter changes is expressed as ai1 period T
i If the number of times the output value of the second counter 01 changes is bi, then Xi""XOi, and if this track number Xi is a certain track number Xj
When calculated from the standard track number Xj and the number of jumps, using the counter @1 (when only 14 is used, Xi = 1 and the second counter 04) and (11), (j≦i-3+゛, °ai+aH-1=b4).Here, + in the Jeannot number of times is forward playback, - is backward playback. This is the case for playback.

Therefore, in a device that performs predicted value control as shown in FIG. 5, the tracks to be traced by the heads (6a) (6b) are determined by equation (1), so the track number xH to be traced during period Ti and the period Ti+1 are The difference mi i+1 from the track number to trace X i+1 is mi i+i
= Xl−HXi −±(ai−2+bi−1bi−2) −−12).

On the other hand, a head (6a) movable in a direction across the track
In (6b), when a track is traced so that this head (6a) (6b) follows a predetermined track at various speeds of the magnetic tape Qt), Id, the i-th trace and the i+1-th trace The field time Hi i+1 of the video signal composed of the playback method is determined by the number of updated tracks ni i+1, where I]o is the field time of one track, and αH is the horizontal synchronization signal shift (H shift) between adjacent tracks. If the time corresponds to Hi i+1=Ho + (ni i-H+ 1) α
It becomes H. Especially in the case of field playback, n1i4-
1 is an even number (nth+x=2mi i+l:mi i+z=
o + fl + f2-), so Hi i+z=Ho+(2mi i+t+1)αH=
= Song 131.

In this example, the reference field time is obtained using the relationship of 2 (21 (3)). That is, as shown in FIG.
a) to the clock signal input terminal of the counter (28a). The output signal of this counter (28a) is
latch circuits (29a) (30a) and (31a)
supply to the series circuit. Further, C33 indicates a pulse signal input terminal to which a pulse Pz shown in FIG. 8B having twice the frequency of the switching pulse PX shown in FIG. 8A is supplied.
The gnosis signal P2 supplied to this pulse signal input terminal G3 is supplied to the reset terminal R1 of the counter (28a) and the latch terminal LK of each of the launch circuits (29a), (30a) and (31a), and at this point the reset and Make it latch. In this case, when the signal aH corresponding to ai is obtained on the output side of the latch circuit (29a) (see FIG. 8C), the output side of each of the latch circuits (30a) and (31a) is The signals ai-1 and a as shown in
i-z is obtained. Further, the output signal of the second counter α value is supplied to the clock signal input terminal of the counter (28b) via the decoder (27b). This counter (28b
) to three latch circuits (29b) (30b).
and (31b). Further, the pulse signal P2 supplied to the pulse signal input terminal is input to a counter (28b
) reset terminal R1 latch circuit (291)) (30b
) and (31b), and reset and latch at this point. In this case, when a signal bi corresponding to bi is obtained on the output side of the latch circuit (29b) (see FIG. 8C), the latch circuit (30b) and (3
At the respective outputs of 1b), signals bi-i and E)i-2 are obtained as shown in FIGS. 8G and H.

This latch circuit (31a) (31b) and (30b)
For example, in the period Ti+1, the output signals of the signals ai-2,
b')-2 and bi-1 are supplied to the arithmetic circuit (to) K.

This 2K1 circuit (c) calculates the formula (2) (% formula %) and outputs lTl1 i+1. The output signal of this first arithmetic circuit (to)! 11ii+1 is supplied to the second arithmetic circuit C(4), and the second arithmetic circuit C34) performs the calculation of equation (3), that is, Hii+x=Ho+(2m1i+z+1)αH, and outputs the reference field time Hii+t. Do as you like. This reference field time Hii+1 is supplied to G error detection circuits.

In addition, (G) indicates a playback video signal input terminal to which the playback video signal reproduced by the head (6a) (6b) is supplied, and the playback video signal supplied to the playback video signal input terminal (to) is input to the playback field. It is supplied to the time detection circuit (37). In this reproduction field time detection circuit I3η, the field time (reproduction field time) of the video signal to be reproduced from the reproduction vertical synchronization signal of the period Ti and the period 'I'i+i and the period Ti and the period Ti-HK Hi'i -Outputs H. This reproduction field time H4'i+1 is rll
i' i + 1 is the number of tracks actually updated, δ
If 1 is a knock, Hi' i+1=Ho 10(-2m1 i+1+ 1
) will be 10δ1.

The error detection circuit (
), and in this error detection circuit C351,
The number of error tracks ei is determined by comparing the reference field time Hj i-M and this reproduction field time H4'i+1.
i+1 is detected and a control signal corresponding to this is output.

The number of error tracks is calculated from the error time ΔH.

△H with is △H=H white+I Hii+i=2(mii+z mi'
i + x) αH + δ1, (2x-1) αH◇ho ((2x + 1) αH Here, by observing We can know i+1.

This ei i+1 is the error from the specified position of the Auzonrusot signal at the position of the track traced in the period Ti+1 as seen from the track traced in the period Ti.
output signal of the arithmetic circuit (c), second arithmetic circuit C14)
The respective timing charts of the output signal of the output signal, the reproduction vertical synchronization signal, the output signal of the reproduction field time detection circuit t37), and the output signal of the error detection circuit G9 are shown in FIGS.
As shown in L and M.

The output signal of this error detection circuit I31 is added to an adder circuit (2) K.
The output signal of this adder circuit (to) is sent to a latch circuit (
39a) and (39b), respectively. These latch circuits (39a) and (39b) are connected to the latch signal input terminal (3
9La) and (39Lb)K supplied Figure 8 N and 0
A reproduced vertical synchronizing signal is obtained during the period 'ri+i as shown in FIG. This latch circuit (39a) and (3
The respective output signals of 9b) are supplied to DA converters (40a) and (40b) that convert the digital signals into analog signals, respectively, and the latch circuits (39a) and (39b)
) are respectively connected to one and the other fixed contacts of the switching circuit (41), and the signals obtained at these movable contacts are supplied to the adder circuit (to). This switching circuit (
The movable contact 41) is switched by a switching pulse Px as shown in FIG. 8A, for example, during a period +1+,
-2°Ti + Ti+2... is connected to the other fixed contact, and the period Tj-x * Ti+1...
... is connected to one fixed contact.

In this case, when the latch circuit (39a) latches, the output signal of this latch circuit (39a) is the switching circuit f41).
is supplied to the adder circuit through the error detecting circuit 0.
This is done when the output signal No. 9 is obtained. The same applies when the latch circuit (39b) latches. Therefore, in this example of FIG. 7, f) -A conversion circuit (40a) and (4
On the output side of 0b), a control signal corresponding to the number of error tracks as shown in FIG. 8 P and Q is obtained. The respective output signals of the 1]-A conversion circuits (40a) and (401)) are supplied to adder circuits (25a) and (25b). The rest of the structure is the same as that shown in FIG.

In this example, the anticipatory control operation is similar to that shown in FIG. Even if such an error occurs, in the next trace, a signal corresponding to the number of error tracks is obtained at the output side of the error detection circuit G9, and correction is made so that the designated track is traced accordingly.

It goes without saying that the present invention is not limited to the above-described embodiments, and that various other configurations can be adopted without departing from the spirit of the present invention.

Effects of the Invention According to the present invention, a rotating magnetic head (6a) (6b
) The rotating magnetic head (6a)
(6b) can trace the track specified by the control signal, and has the advantage that a good reproduced image can always be obtained even in variable speed reproduction such as high-speed search slow motion reproduction.

[Brief explanation of the drawings] Fig. 1 is a schematic plan view of a rotating drum for explaining an example of a magnetic recording/reproducing device, Fig. 2 is a partially cutaway side view of Fig. 1, and Fig. 3 is a magnetic recording/reproducing device. FIG. 4, FIG. 6, and FIG. 8 are diagrams for explaining the present invention, respectively, and FIG. 5 is a configuration diagram showing an example of a conventional magnetic recording/reproducing device. , FIG. 7 is a block diagram showing an embodiment of the magnetic recording/reproducing apparatus of the present invention. (2) is a rotating magnetic head device, (6a) and (6b) are rotary magnetic heads, (7a) and (7b) are bimorph plates, respectively, αXun is a first counter, αl is a second counter, (to) and (34) are respective calculation circuits, c19 is an error υ detection circuit, (to)1 is a reproduced video signal input terminal, and r37 is a reproduced field time detection circuit. Hidemori Matsukuma ■゛: Figure 1 Figure 2 Figure 3 ct Figure 4 B Dark procedure amendment 1, Indication of case Patent application No. 172003 of 1988 2, Title of invention Magnetic recording and reproducing device 3, Relationship with the case of the person making the amendment Patent applicant representative director Dai K'7 Betsu Kai 1 (338B) Patent attorney Tei Ito 5, Attached to 1 of the amendment order 6, Showa, Number of inventions increased by amendment 7. Amendment Column 8: Detailed explanation of the invention in the specification 8. Contents of the amendment (11 Specification, page 12, lines 6 to 9: ``This is a pulse...this signal 86 Correct the text "J" to "this output signal". In the same page, page 13, line 8, "time t3" should be corrected to "time t2J".
K Correct. (3) Same, page 13, line 9, "time t5" is corrected to "time t3." (4) Same, page 20, line 16, replace “decoder” with “
Kawantar (6th when the output signal of 141 jumps)
A decoder that outputs pulses as shown in Figure FK is corrected. Same, page 21, line 12 [Decoder (27b) is replaced with "
The decoder (27b) which outputs the pulse shown in FIG. 6H when the output signal of the Kawanta α detector jumps I'VC is corrected. (6) Same, page 24, lines 1-2 [observe...
Can be done. '' should be corrected to ``The inverse of the sign that satisfies is 101.i+l.''

Claims (1)

[Claims] Attach multiple rotating magnetic heads to an electro-mechanical conversion element,
In a magnetic recording/reproducing device configured such that the rotating magnetic head is shifted in a direction across tracks of the magnetic tape by a control voltage applied to the electro-mechanical transducer, Change the repetition frequency (
The pulse is counted for each field of the video signal to obtain a first counting output, and a frequency n (n is a positive integer other than 1) times the pulse is set to the reproduction state of each of the rotating magnetic heads. Each time the count is switched, a second count output is obtained by counting, and the count output obtained by adding (or subtracting) the second count output to the first count output is used as the count output for each of the above. Sampling and holding is performed at the end of the reproduction period of the rotating magnetic head, and a reference field time is formed based on the output of the first and second counts, and the error track is determined by comparing the reference field time and the reproduction field time. A control signal corresponding to the number of the rotary magnetic heads is generated, and a sum signal of the sampled and held signal and the control signal is generated during the period when each of the rotary magnetic heads is not in contact with the magnetic tape. A magnetic recording/reproducing device characterized in that the magnetic recording/reproducing device is configured to supply electricity to an electro-mechanical transducer.