JPH04163701A - dubbing system - Google Patents

Abstract

PURPOSE:To make it possible to perform high-speed dubbing with a rotary-head- type apparatus whose constitution is simple by using N pieces of rotary heads which are rotated in close proximity, and regenerating data signals and tracking- controlling pilot signals on N pieces of neighboring tracks on a first tape-shaped recording medium as the signals of N channels. CONSTITUTION:Regenerating amplifiers 46a and 46b regenerate data signals and tracking-controlling pilot signals on N pieces of neighboring tracks on a first tape-shaped recording medium as the signals of N channels by using N pieces of rotary heads Ha and Hb. Bypass filters 93a and 93b remove the tracking-controlling pilot signals. Adders 94a and 94b generate N kinds of pilot signals in plural kinds of tracking-controlling pilot signals in parallel. The signals of N channels and N kinds of the pilot signals are added through the bypass filters 93a and 93b respectively. The signals of N channels are recorded with N pieces of the neighboring tracks being formed in a second tape-shaped recording medium. Thus, the high-speed dubbing can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a dubbing system, and more particularly, to a dubbing system for dubbing a large number of tracks in which a plurality of types of tracking control pilot signals having different frequencies are sequentially multiplexed onto information signals for each track. The present invention relates to a dubbing system for a tape-shaped recording medium formed with.

[Conventional technology]

As mentioned above, there is a home-use helical scan video tape recorder (VTR) as a device for recording and reproducing information signals on each track of a tape-shaped recording medium.The following describes a dubbing system using this type of VTR. explain.

Generally, a so-called rotating two-head helical scan type VTR is known as a home VTR. Figure 6 (A), (B
) is a diagram showing a general head arrangement of this type of VTR. In FIGS. 6(A) and (B), 1 is a magnetic tape, 2
Reference numerals a and 2b denote tape guides for winding the tape 1 around the outer periphery of the rotating drum 3 over an angular range of 180 degrees or more.

These are rotating heads that are attached to the rotating drum 3 with a phase difference of 180' from each other, and as shown in the figure (they are attached at the same height in the rotation axis direction and have different azimuth angles.Heads HA, HB As is well known, 180°
It records and reproduces one field's worth of video signals while rotating.

In this type of VTR, the length of the track on which the video signal for one field is recorded is predetermined in the standard. Therefore, the diameter of the rotating drum 3 is inevitably determined accordingly. Therefore, the diameter of the drum 3 cannot be reduced, which hinders the miniaturization of VTRs.

Therefore, the following VTRs have been proposed as VTRs whose drum diameter can be reduced. Figures 7 (A) and (B) show a conventional VTR using a small diameter drum.
FIG. In the figure, Ha and Hb are rotary heads having different azimuth angles, and rotate once during one field period of the video signal. Rotating head Ha,
The Hb's are arranged to rotate close to each other with a phase difference of a minute angle θ0, and are mounted at the same height in the rotation axis direction as shown in the figure.

The tape 1 is wound around the drum 3 over an angular range of 300° or more, and the rotating heads Ha and Hb each have 3
000 One field worth of video signal is recorded during the rotation. That is, the video signal for one field is recorded in a period shorter than the original period of one field of the video signal.

Therefore, the video signal recorded by this type of VTR is N.
When assuming a TSC signal, instead of a normal NTSC signal, that is, a signal with a vertical scanning frequency (fv) of 60 Hz and a horizontal scanning frequency (fh) of 15.75 kHz, an fv of 6
0Hz, fh is 18.9 (15,75X615)
Must be of kHz.

In other words, the video signal recorded by this type of VTR must be a normal television signal compressed in time axis to 5/6 in units of one field, or a signal obtained from a dedicated video camera.

The dedicated video camera described above scans a screen with an aspect ratio of 9:10 (indicated by the dotted line Y in Figure 8), and a screen with an aspect ratio of 3:4, which is indicated by the solid line X in Figure 8, is the effective screen. It is output within the 5/6 field period. The heads Ha and Hb shown in FIGS. 7(A) and 7(B) are 5.
Since one track can be formed within a /6 field period, it is possible to record one field of video signals on one track. Video signals can be recorded in a format similar to that of . That is, the V of the head arrangement as shown in FIG.
If the video signal is recorded by the TR as described above, the drum diameter can be reduced to 315 mm compared to the VTR with the head arrangement shown in FIG.

Furthermore, if the reproduced video signal is time-extended by 615 times per field, the same effect can be achieved with the VTR with the head arrangement shown in FIG. 7 as with the VTR with the head arrangement shown in FIG.

[Problem that the invention is trying to solve]

By the way, when dubbing a tape using two VTRs, for example, when dubbing two hours of video information, real-time dubbing is generally used, in which standard television signals are transferred over two hours. be.

Now that camera-integrated VTRs are becoming more popular and many people want simple editing and dubbing, it is extremely troublesome for users who are familiar with high-speed dubbing with tape recorders to perform such real-time dubbing. . For example, 2
It takes a lot of time and effort to delete a small portion of a video that has been shot incorrectly.

In addition, VT using a small drum as shown in FIG.
When dubbing is performed in R, a video signal whose time axis is compressed to 5/6 in units of one field is first expanded in time axis to form a standard television signal, and then again
Various processes such as time axis compression for each field are required, making it extremely difficult to achieve high-speed dubbing.

In particular, dubbing itself is extremely difficult in a type of VTR that sequentially multiplexes a plurality of types of pilot signals into information signals for each track for tracking control. That is, in this type of VTR, tracking control is performed by comparing the leakage of the reproduced pilot signal from both adjacent tracks of the track being traced in the reproduced signal of a certain reproduction head. The signal always includes the leakage portion of the pilot signal. Therefore, if this reproduced signal is recorded as is on another recording medium, the recorded pattern on the original recording medium cannot be faithfully reproduced. Therefore, when reproducing the recording medium after dubbing, good tracking control cannot be performed.

SUMMARY OF THE INVENTION In view of the above-mentioned background, it is an object of the present invention to enable high-speed dubbing using a rotating head type device with a simple configuration, even on a recording medium in which a tracking control pilot signal is recorded together with an information signal. .

[Means to solve the problem]

For this purpose, according to the present invention, it is possible to reproduce a tape-shaped recording medium in which a large number of tracks are formed, in which a plurality of types of tracking control pilot signals having different frequencies are sequentially multiplexed onto an information signal for each track. In a dubbing system, information signals and tracking control pilot signals on N adjacent tracks on a first tape-shaped recording medium are converted into N-channel signals using N rotary heads that rotate closely. A reproducing means for reproducing, a removing means for removing a tracking control pilot signal from the N channel signals from the reproducing means, and generating N types of pilot signals among the plurality of types of tracking control pilot signals in parallel. a generating means, an adding means for respectively adding the N-channel signal via the removing means and the N types of pilot signals output from the generating means, and an N-channel signal output from the adding means,
The second tape-shaped recording medium has a recording means for recording while forming N adjacent tracks on the second tape-shaped recording medium.

[Operation] As mentioned above, by using N rotating heads that rotate closely, the rotational speed of the rotating heads can be increased,
To perform dubbing on a tape-shaped recording medium in which a large number of tracks in which a plurality of types of tracking control pilot signals are sequentially multiplexed is formed at N times the speed without increasing the diameter of a drum holding a rotating head. It became possible. Furthermore, it can be seen that the pilot signal is also in the same recording state on the original tape-shaped recording medium.

〔Example〕

Hereinafter, a dubbing system according to an embodiment of the present invention will be described in detail.

FIG. 1 (A) is a diagram showing a schematic configuration of a dubbing system as an embodiment of the present invention, and FIG. 2 (A) and (B
) is a diagram showing head configurations of a reproducing side VTR and a recording side VTR of the system of FIG. 1(A).

In the system of this embodiment, the head configurations of the reproducing side and recording side VTRs are different from the head configurations shown in FIGS. 7(A) and 7(B) in that the heads Ha and Hb are one track pitch (ITP) in the direction of the rotation axis. The difference is that the heads Ha and Hb are shifted and placed on an electrostrictive element 61 as an actuator for displacing them in the direction of the rotation axis.

In FIG. 1(A), P is a playback VTR, and R is a recording VTR. For the sake of simplicity, only the parts related to playback and recording functions are disclosed, but both VTRs have recording and playback functions. It can also be a configuration.

40 and 41 are magnetic tapes whose recording format is the same as that of the VTR having the head configuration shown in FIG. 6 described above.

First, the normal playback operation of the playback VTR shown in FIG. 1(A) will be explained. When a normal playback command is issued from the operation unit 34, the system controller 35 activates the servo circuit 17.
to control the capstan motor 42, and the capstan C transports the tape 1 for 72 minutes per field period. On the other hand, the system controller 35 controls the servo circuit 17 to control the drum motor 43 so that the drum D rotates once per field period. At this time,
Head Ha.

Hb sequentially traces each track one track at a time, but during one field period in which the head Ha traces the track Ta with the azimuth angle corresponding to the head Ha, the azimuth angle corresponding to the head Hb is traced. This means that the head Hb is tracing the track Tb,
During this period, the heads Ha and Hb can take out reproduction signals. On the other hand, following this one field period (next one field period), the head Ha traces the track Tb, and the head Hb traces the track Ta, making it impossible to extract the reproduced signal.

FIG. 3 is a timing chart for explaining the operation of each part of the dubbing system of this embodiment. In the figure, A l
, B l , A Q . . . indicate a video signal for one field. Originally, the video signal as shown in FIG. 3(a) is transmitted to the third
The data is reproduced as shown in FIGS. (C) and (d). In addition, in the VTR with the head arrangement shown in FIG. 7 mentioned above, the head arrangement shown in FIG.
) is obtained.

The reproduced signal from the head Hb is delayed by l field period in the 1-field delay circuit 18, and is input to the switch 11 together with the reproduced signal from the head Ha. The switch 11 is connected to the head Ha side during the 1-field period in which the heads Ha and Hb can reproduce signals, and is connected to the delay circuit 18 side during the 1-field period adjacent thereto.

As a result, the output signal of the switch 11 becomes a signal obtained by simply compressing the time axis of each field signal to 5/6, as shown in FIG. 3(b).

FIG. 4 is a diagram for explaining signals reproduced by the VTR of the system of this embodiment. FIG. 4(a) shows the spectrum arrangement of the signal recorded and reproduced by the VTR with the head arrangement shown in FIG. 6, and FIG. 4(b) shows the spectrum of the signal recorded and reproduced by the VTR in the system of this embodiment. Show placement. In the figure, Y is an FM modulated luminance signal, A is an FM modulated audio signal, C is a low frequency conversion chroma signal, and P
show four types of pilot signals for tracking control, which will be described later.

As is clear from FIG. 4, the frequency of the signal output from the switch 11 in this embodiment is 1.2 times that of the reproduced signal of the VTR with the head arrangement shown in FIG. The operating frequency is 1.2 times that of the VTR with the head arrangement shown in FIG.

The reproduced video signal processing circuit 12 obtains a reproduced luminance signal obtained by FM demodulating the FM modulated luminance signal in the signal output from the switch 11 and frequency-converts the chroma signal converted to the low frequency band to the original band. A reproduced video signal obtained by mixing the reproduced chroma signal is output. The synchronization separation circuit 16 separates the synchronization signal from the reproduced video signal and supplies it to the servo circuit 17, which is used as a reference signal for controlling the drum motor 43 and capstan motor 42 as described above.

Here, tracking control in the playback device of this embodiment will be explained.

As shown in FIG. 1(A), only the reproduction signal of the head Ha is supplied to the ATF circuit 91;
It will be supplied to the input terminal 100 of B). terminal 1
The signal input to 00 is passed through low pass filter (LPF) 1.
01, and only the pilot signal is separated. In this embodiment, as shown in FIG. 4, the frequency of the reproduced signal is 1.2 times the normal frequency. Here the normal 1
．． Four types of pilot signals with twice the frequency (flS
f2, f3, f4) The frequency that can extract medium and high frequency pilot signals and cut chroma signals is 400.
Hz, and the cutoff frequency of this LPFIOI is 40
It was set to 0Hz.

Here, the pilot signal separated by this LPFIOI will be considered. As mentioned above, each head Ha sequentially traces each track one track at a time.
A track Ta having an azimuth angle corresponding to the head Ha and a track Tb having an azimuth angle corresponding to the head Hb are alternately traced. However, since the frequency of the pilot signal is sufficiently low, it is not affected by the azimuth angle. That is, when tracking control is performed normally, the pilot signal mainly reproduced by the head Ha is sequentially switched one by one every field period, for example, in the order of f1 → f2 → f3 → f4. .

Therefore, during normal reproduction, the multiplier 103 to which the output of LPFlol is supplied receives four types of local pilot signals, fl, f2, f3, and f4 output from the local pilot signal generator 111, for each field. The switch 102 may be used to select and provide the signals in the order of f1→f2→f3→f4. As is well known, the output of this multiplier 103 is BPF 104a, 1, which separates frequency components corresponding to the frequency difference between pilot signals of two adjacent tracks.
04b. In a conventional VTR with a head arrangement as shown in FIG. 6, the frequency difference between the pilot signals of these two adjacent tracks is generally fH (fH is the horizontal scanning frequency) and 3fH. , assuming this, the BPFs 104a and 104b of this embodiment
The passing frequencies of are 1.2fH and 3.6fH.

The output signals of these BPFs 104a and 104b are input to amplitude detection circuits 105a and 105b, and the Talostalk levels from both adjacent tracks of the control target track are detected, respectively. This detection circuit 105a.

The output of 105b is converted into a signal indicating the amount of tracking deviation by a difference circuit 106. Amplitude detection circuit 105a.

As is well known, the frequency components separated by 105b correspond to crosstalk components from adjacent tracks that are opposite to each other for each field with respect to the control target track.
A switch 108, which is switched for each field, generates a signal indicating the amount of tracking deviation and its direction.

The gate circuit 109 gates only the valid period of the signal output from the switch 108, that is, the period when the head Ha is tracing on the tape 40, and outputs the above-mentioned servo signal via the terminal 110 as a tracking error detection signal (ATF signal). The signal is supplied to the circuit 17. Note that this gate circuit 109
The gate timing of the drum D and the switching timing of the switches 102 and 108 are determined by the control signal generation circuit 112 according to a rotation detection signal obtained from a detector (not shown) that detects the rotation of the drum D.
controlled by.

The servo circuit 17 controls the gear stan motor 42 according to the low frequency component of this ATF signal, and controls the head HaSHb.
The rotation of the capstan C is controlled so that it traces the center line of the track Ta5Tb. Further, the circuit 17 is
An electrostrictive element 61 composed of a bimorph plate (described later) is controlled in accordance with the high frequency component of the TF signal, so that the head follows the undulations of each track.

Returning to FIG. 1A, the reproduced video signal from the reproduced video signal processing circuit 12 can also be output from the terminal 15c. However, since this reproduced video signal is a signal in which the signal of each field is time-axis compressed to 5/6, when supplying it to an external monitor, etc., the time-axis expansion circuit 13 compresses the time axis of each field signal to 615. It is expanded and output from the terminal 14.

Note that since the audio signal is not directly related to the present invention, a description thereof will be omitted in this specification.

Next, the normal recording operation of the recording side VTR in FIG. 1(A) will be explained. The recording side VTR in the system of this embodiment is assumed to be a camera-integrated VTR, and the above-mentioned dedicated video camera (overscan camera) 31
have. The head configuration is the same as that of the reproducing VTR, but a ``''' is added for distinction. The camera 31 outputs a video signal as described above (as shown in FIG. 3(b)) and inputs it to the B terminal of the switch 22, while 32 is an external input terminal, as shown in FIG. 3(a). A continuous video signal is input.The time axis compression circuit 33 compresses the time axis of this video signal to 5/6 for each field as shown in FIG.
A signal as shown in b) is inputted to the C terminal of the switch 22. Furthermore, the terminal 21c is a terminal for inputting a video signal as shown in FIG. 3(b), and the video signal inputted to the terminal 21c is supplied as is to the A terminal of the switch 22.

When the normal recording mode is selected by the operation unit 36 and the switch 22 is instructed as to which input signal to record, the switch 22 records the selected signal in the video signal processing circuit 2.
3 and the synchronous separation circuit 24.

The servo circuit 26 receives information supplied from the system controller 37 according to the operation of the operation unit 36, and the synchronization separation circuit 2.
Using the synchronization signal separated at 4, the capstan motor 4
4, the capstan C' transports the tape 41 one track per field period, and the drum motor 45 moves the drum D' per field period.
Control so that it rotates once.

The recording video signal processing circuit 23 performs FM modulation on the luminance signal and converts the subcarrier frequency of the chroma signal to a low frequency, as shown in FIG.
A signal as shown in b) is provided to the switch 25. The switch 25 is alternately connected to the head Ha' side and the head Hb' side for each field.

As a result, the signals supplied to the heads Ha' and Hb' become as shown in FIGS. 3(c) and 3(d).

92 is 4 which generates a pilot signal for tracking control.
This is a 4f generation circuit, and FIG. 1(C) shows this 4f generation circuit 9.
The specific configuration of 2 is shown below.

In FIG. 1(C), 210 is a terminal to which a pulse generated by a sensor (not shown) every time the drum D' rotates once is input. That is, since the drum D' rotates once in one field period, one pulse is inputted to the terminal 2101 every other field.

During normal recording, the switch 211 is connected to the N side, and the upper bit (209a) of the 2-bit counter 209 is output. The pulse from the terminal 210 is input to the 2-bit counter 209, and its upper bit (20
9a) is inverted every two field periods, and the lower bit (2
09b) is inverted every one field period.

The selection circuits 214a and 214b are the upper bits (209a)
Accordingly, the pilot signal to be output is changed every two field periods. During the two-field period when the selection circuit 214a is outputting fl, the selection circuit 214b outputs f2, and during the next two-field period, the selection circuit 214a outputs f3.
The selection circuit 214b will output f4.

On the other hand, the lower bits of the 2-bit counter 209 (209b
) controls the gates 215a and 215b, and
The pilot signals output from the selection circuits 214a and 214b are gated every 1 and F. Switches 216a, 21
Since the switch 6b is connected to the N side during normal recording, the pilot signal is generated from the switches 21.7a and 217b every one field period, that is, only in the field where the heads Ha' and Hb' record the video signal. Ru. The outputs of these terminals 217a and 217b are sent to the adder 94a.
, 94b. Therefore, adder 94a has fl
, f3, and f2 and f4 are alternately supplied to the adder 94b every two field periods.

The rotary heads Ha' and Hb' are shifted from each other by one track pitch in the direction of the rotation axis, and the head Ha'
traces the tape 4] slightly ahead of the head Hb'. As a result, two tracks are simultaneously formed by the heads Ha' and Hb' once every two fields, and as a result, recording similar to that of a VTR whose head arrangement is shown in FIGS. 6 and 7 becomes possible.

The signal output from the switch 22 scans the monitor screen from the top edge to the bottom edge in one field period and within 5/6 field periods, and changes the horizontal scanning frequency to the normal 5
76 dedicated monitor (overscan monitor) 49
and the recording status is monitored. This monitor 49
is used as a so-called electronic viewfinder in a camera-integrated VTR. In addition, a time axis expansion circuit 16 is provided to expand the time axis of each field signal to 615 so that it can be monitored on an external monitor.The output of this time axis expansion circuit 16 is shown in FIG. 3(a). The signal is outputted from the terminal 17 as a normal video signal.

Next, the operation during dubbing using the above-mentioned reproduction side and recording side VTR will be explained.

Output terminals 15a and 15b of the reproduction side VTR and the recording side VT
Connect the input terminals 21a and 21b of the R and playback side VTR.
When the dubbing mode is specified using the operating section 34 of the VTR and the operating section 36 of the recording VTR, the servo circuit 17.26 controls the capstan motor 42.44, and the capstan cS
c' transports the tape 40, 41 for two tracks per field period, and the drum motor 44.
Drums D and D' are 1 per field period.
Control the rotation.

As a result, the playback heads Ha and Hb each trace the tape 40 every other track, and the playback heads Ha and Hb trace only the tracks Ta and Tb, respectively.

However, since the transport speed of the tape 40 is different from that during normal playback described above, the heads Ha and Hb cannot trace parallel to the tracks. This will be explained using FIG. 5. In FIG. 5, 0 is a vector corresponding to the running of the tape 40 during normal playback, and υD is a vector corresponding to the rotation of the playback heads Ha and Hb.

is their composite vector. During dubbing, the vector corresponding to the running of the tape 40 becomes 2υT, and the composite vector becomes 1. Let this vector be υ. In order to match the vector Tc, in this embodiment, the electrostrictive element 61 made of a bimorph plate provides a motion corresponding to the vector Tc. That is, during the period of 5/6 field during which the head HaSHb traces the tape 40, the electrostrictive element 61 continuously shifts the head HaSHb by one track in the direction of the rotation axis, and during the period of the remaining 1/6 field. , the reset operation is repeated for each field. This operation is provided by servo circuit 17. This causes the head Ha.

Hb will trace in a direction parallel to the track.

In FIG. 2(B), 61 is a bimorph plate, and 62
is a terminal to which a control signal from the servo circuit 17 is applied;
63 is a sensor such as a strain gauge.

This sensor 63 is capable of detecting the absolute position of the heads Ha and Hb in the rotation axis direction, and is provided to accurately determine the positions of the heads Ha and Hb during normal recording and reproduction. , the output of the sensor 63 is fed back to the servo circuit 17.

Here, the tracking control operation during dubbing will be explained.

The ATF circuit 91 is supplied with only the reproduction signal of the head Ha as in normal reproduction. Here, the LP of FIG. 1(B)
Considering the pilot signals supplied to the FIOI, since the head Ha reproduces only the track Ta, it is necessary to mainly reproduce the pilot signals fl and f3 for each field period, as shown in FIG. 3(h). become. Therefore,
The switch 102 also receives fl, as a local pilot signal.
If f3 is output alternately every field period, an ATF signal will be obtained in the following circuit. However, in this case, the frequency components separated by the amplitude detection circuits 105a and 105b are always from adjacent tracks in the same direction, so the switch 108 is fixed. The operation of the gate circuit is the same as during normal reproduction. In this way, the ATF signal is supplied from the ATF circuit 91 to the servo circuit 17.

The servo circuit 17 controls the capstan motor 42 in accordance with the low frequency component of the ATF signal, and controls the electrostrictive element 61 in accordance with the high frequency component, as in normal reproduction.

The reproduced signals of the head HaSHb during this dubbing are shown in FIGS. 3(e) and 3(f). This signal is the reproduction amplifier 4
6a, 46b to output terminals 15a, 15b.

The recording side VTR receives the information from the reproduction side VTR as shown in Fig. 3(e), (
The signals shown in f) are received from terminals 21a and 21b, and are sent to a bypass filter (HP) via amplifiers 47a and 47b.
F) Supplied to 93a and 93b. HPF93a, 93b
removes the reproduced pilot signal component and outputs only the video signal component and audio signal component shown in FIG. 4(b). The output signals of the HPFs 93a and 93b are sent to an adder 94a.
194b, and the pilot signal generated by the four-ring generating circuit 92 is added.

Here, the first part regarding the operation of the 4-double generation circuit during dubbing will be explained.
This will be explained with reference to Figure (C). Terminal 20 in Figure 1(C)
A signal from the terminal 21a in FIG. 1(A), that is, a reproduction signal from the head Ha of the reproduction side VTR is input to 0. This signal is 1 if tracking control is performed stably.
A field in which fl is mainly reproduced and a field in which f3 is mainly reproduced are repeated every field period.

201 is a bandpass filter (BP
F), 202 is a BPF that separates the f3 component, and their outputs are compared by a comparator 204. The comparator 204 outputs a low level (LO) when there are many f1 components, and outputs a high level when there are many f3 components. Mono multi (
MM) 207 delays the pulse from the terminal 210 by a predetermined period and outputs the pulse during the period when the reproduced signals are obtained from the heads Ha and Hb.

The D flip-flop 206 uses the pulse from the MM 207 as a clock to latch the output of the comparator 204, and the output of the D flip-flop 206 is used as the D input of the D flip-flop 208. The clock of the D flip-flop 208 is a pulse from the terminal 210, and the Q output of the D flip-flop 208 is Hi when the main reproduction pilot signal of the head Ha is fl, and L when the main reproduction pilot signal of the head Ha is f3.
It becomes O. Therefore, the Q of this D flip-flop 208 is
The output is inverted every field period, and the selection circuits 214a and 214b are controlled via the switch 211 connected to the D side during dubbing. Selection circuit 2
14a and 214b indicate that the Q output of the D flip-flop is H.
When it is i, fl and f2 are output, and when it is Lo, f3 and f4 are output. The outputs of these selection circuits 214a and 214b are connected to a switch 216a.

It is supplied to terminals 217a and 217b via the D side of 216b, and is supplied to adders 94a and 94b in FIG. 1(A). The output signals of adders 94a and 94b are supplied to heads Ha' and Hb', respectively. Head Ha'
, Hb' are generated by the electrostrictive element 61'.
The same displacements as a and Hb are given, and this is controlled by the servo circuit 26.

As a result, the heads Ha' and Hb' trace the tape 41 in the same direction as during normal recording, and two fields of video signals and tracking control pilot signals are sent to adjacent tracks with different azimuth angles. are recorded at the same time. This operation is performed every one field period. This allows 2 times the normal recording/playback operation.
Achieves dubbing at twice the speed. Furthermore, in this embodiment, the relationship between the video signal and the pilot signal recorded on each track is maintained as is on the tape 4°. That is, the same pilot signal that has been superimposed on the tape 40 is also superimposed on the tape 41.

In FIG. 1(C), the output of the switch 211 is at the terminal 21.
2 to the system controller shown in FIG. 1(A), which determines recording start and end timings. For example, if recording is started and ended in synchronization with the rising edge of the output of the switch 211, recording will always start from the track where fl is recorded, whether during normal recording or dubbing, and the track where f4 will be recorded. Recording ends.

Even if the tape recorded in this way is loaded into the playback VTR and dubbed again using the system shown in FIG. Up to the truck. This is especially true for PAL and S, which have the same signal format every two frames.
It is extremely effective as a dubbing system for ECAM signals in that it can maintain signal continuity.

According to the dubbing system of the embodiment described above, a VTR with a small drum diameter and a type that multiplexes pilot signals for tracking control is used, without increasing the number of heads, and with simple installation of dubbing terminals and amplifiers. By simply adding a circuit, it became possible to perform high-speed dubbing at twice the normal speed.

In addition, by providing a bimorph board, etc., it can be used as a VTR for normal recording and playback, and it can achieve good tracking that follows the undulations of the track during playback and dubbing, making the system more efficient. It can be used.

In the above embodiment, the number of heads rotating close to each other is defined as two, but it is generally determined that the number of heads is N depending on the desired dubbing speed.
(N is an integer of 2 or more). however,
When dubbing is performed using a head arrangement as in the above embodiment, assuming a format that performs azimuth recording, the number of heads must be an even number.

In addition, in this specification, the dubbing system was constructed assuming a VTR using a small drum, but the present invention can be applied to any rotating head type information recording/reproducing device such as a DAT (digital audio recorder). Therefore, the embodiments can be modified as appropriate within the scope of the claims.

〔Effect of the invention〕

As explained above, according to the dubbing system of the present invention, high-speed dubbing of a tape-shaped recording medium on which a pilot signal for tracking control is recorded is performed using a rotary head type device that is small and has a simple configuration. It has become possible to realize this.

[Brief explanation of the drawing]

FIG. 1(A) is a diagram showing a schematic configuration of a dubbing system as an embodiment of the present invention, FIG. 1(B) is a diagram showing a specific configuration example of the ATF circuit in FIG. 1(A), Figure 1 (C) is a diagram showing a specific example of the configuration of the 4f generation circuit in Figure 1 (A), Figures 2 (A) and (B) are the system (7) VTR in Figure 1.
3 is a timing chart showing the signal processing timing of each part in the system of FIG. 1; FIG. 4 is a diagram for explaining video signals handled by the system of FIG. 1; The figure is a diagram for explaining the head trace trajectory during normal recording and playback and dubbing in the VTR of the system shown in Figure 1. Figures 6 (A) and (B) show the head arrangement of a conventional general VTR. Figure 7 (A) and (B) show conventional VT using a small drum.
FIG. 8 is a diagram for explaining a video camera used exclusively in a VTR whose head arrangement is shown in FIG. 7. Ha, HbSHa', Hb'-respectively rotating head c,
c'...capstan D, D'...each drum 17.26...each servo circuit 18.19...each 1 field delay circuit 42.44
...Castan motors 40, 41, respectively...Magnetic tapes 46a, 46b, respectively...Reproduction amplifiers 47a, 47, respectively
b... Respective recording amplifiers 61, 61'... Electrostrictive element 91 as an actuator... ATF circuit 92... 4f generating circuit 93a193 as generating means
b...Bypass filters 94a and 94b, each serving as a removing means; Adder 1, each serving as an adding means
01...low-pass filters 102, 108... are respectively switch 103...multiplier 109...gate circuit 111...local pilot signal generation circuit 112...
...Control signal generation circuit lθr

Claims (2)

[Claims] (1) A dubbing system for duplicating a tape-shaped recording medium in which a large number of tracks are formed in which a plurality of types of tracking control pilot signals having different frequencies are sequentially multiplexed into information signals for each track, the dubbing system including: reproducing means for reproducing information signals and tracking control pilot signals on N adjacent tracks on a first tape-shaped recording medium as N-channel signals using N rotating heads; removing means for removing tracking control pilot signals from the N channel signals from the reproduction means;
generating means for generating different types of pilot signals in parallel; addition means for respectively adding the N-channel signals that have passed through the removal means and the N types of pilot signals output from the generation means; A dubbing system comprising: recording means for recording N-channel signals while forming N adjacent tracks on a second tape-shaped recording medium. (2) The tracking control pilot signal includes four types of pilot signals, and the generating means includes a pair of pilot signal generators that alternately output two types of pilot signals. The dubbing system described in (1).