JPS61144702A - Rotary head type recording or reproducing device - Google Patents

Abstract

PURPOSE:To grasp the recording state of the entire area by dividing a tape type recording medium lengthwise into plural areas and deciding on the recording state of each area on the basis of the generation timing of the RF signal in the output of a rotary head. CONSTITUTION:The magnetic tape 1 is divided lengthwise into plural areas and an information signal is recorded in and reproduced from every area by rotary heads 3 and 4 which traces the tape 1 in its width direction. When the signal is recorded, a pilot signal for tracking from a pilot signal generator 23 is recorded together with the output of a PCM audio circuit 22 and when the signal is reproduced, a reproduction output is obtained from the circuit 22 and tracking is controlled by an ATF circuit 26. The RF signal in the outputs of the heads 3 and 4 is supplied to an area decision circuit 28 through a gate circuit 27 which is controlled with output pulses of a gate pulse generating circuit 17 and the circuit 18 decides whether each area is already recorded or not, so that the decision result is displayed on a display device 29. Thus, the recording states of all areas are grasped.

Description

Detailed Description of the Invention [Technical Field] The present invention relates to a rotary head type recording or reproducing device, and in particular, a tape-shaped recording medium is divided into a plurality of regions in its longitudinal direction, and each region is divided into a plurality of regions by a rotary head that traces in the width direction. The present invention relates to a device that records or reproduces information signals for each area.

<Description of Prior Art> In recent years, high-density recording has been pursued in the field of magnetic recording, and even in video tape recorders (VTRs), the running speed of the tape has been reduced to perform even higher-density magnetic recording. There is. For this reason, if audio signals are recorded using a fixed head as in the past, the relative speed cannot be maintained at a high rate, resulting in degraded playback quality.

One way to solve this problem is to make the track formed by the rotating head longer than before.

There is a method of sequentially recording time-base compressed audio signals in the extended portion.

For example, in a rotating two-head helical scan type VTR, more than 1,800 magnetic tapes were conventionally wound around a rotating cylinder.

A VTR has been devised in which a rotary cylinder is wound with a length of (180+θ)0 or more, and an audio signal converted into PCM and time-axis compressed is recorded on the excess wound portion. FIG. 1 is a diagram showing a tape running system of such a VTR, and diagram t52 is a diagram showing a recording locus on a magnetic tape by the VTR shown in FIG.

In the figure, 1 is a magnetic tape, 2 is a rotating cylinder, 3.4
5 is a video area portion of a track formed on the tape 1, and 6 is a turntable (audio area portion). Video area 5 is 1 of rotating cylinder 2
The part where head 3.4 traced the tape at 80°,
The audio area 6 is the part where the heads 3 and 4 traced the tape at 00 minutes of the rotating cylinder 2. In addition, f1 to f4 in FIG. 2 indicate the frequencies of tracking pilot signals superimposed on each track using the well-known four-frequency method, and the relationship between the frequencies is (f2-ft)=f3-fa.
*fH, f4-f2Φ2f) (However, f
H indicates the horizontal scanning frequency of the video signal.

The sound quality when playing back the audio signal which has been converted into PCM and time axis compressed in the audio area in this way is quite high and is comparable to the sound quality of an audio dedicated device that records and plays back analog signals.

On the other hand, a proposal has been made to record another audio signal in the video area 5 of the above-mentioned VTR. That is, for example, when θ=36, if the rotary head rotates by 180 degrees, the audio area 6 will be expanded to 5 other areas.
There will be one. By recording time-base compressed audio signals independently in each area, an audio-only tape recorder capable of recording a total of six channels of audio signals can be obtained.

This tape recorder will be briefly explained below. FIG. 3 is a diagram showing the tape running system of the above-mentioned tape recorder, and FIG. 4 is a diagram showing the recording locus on the tape by this tape recorder. Note that the numbering is the same as in FIGS. 1 and 2.

In FIG. 4, CHI-CH6 are respectively head 3 or head 4 from A to B in FIG.

This is an area in which an audio signal is recorded during the period of tracing from B to C, from C to D, from E to F, and from F to G. Audio signals can be recorded separately in each area, and so-called azimuth overwriting is performed in each area.

The tracks of each area CHI-CH6 do not need to be on the same straight line, and a pilot signal for tracking control is recorded in each area, but a predetermined rotation (f1 → f2 → f3 → f4 ) shall be recorded.

There is also no correlation between these areas.

Also, the area shown as CHI-CH3 is
Recording and reproduction are performed when the vehicle is traveling at a predetermined speed in the direction shown by arrow 7, and recording and reproduction is performed in the area indicated by CH2-CH2 when it is also traveling in the direction shown by arrow 9. Therefore, the fourth
As shown in the figure, the inclination of each track in the area indicated by CHI-CH3 and the inclination of each track in the area indicated by CH2-CH2 are slightly different. However, regarding the difference in relative speed at this time, compared to the difference due to the rotation of the head 3.4, the tape l
The damage caused by running is extremely small and should not be a problem.

FIG. 5 is a time chart of recording and reproduction of the tape recorder as described above. In FIG.
It is a 30H2 (7) square wave that repeats "high level (H)" and "low level (L)" in 0 seconds. Also, (b) is a PG with the opposite polarity to PG (a). Here PG (a)
are H, PG while the head 3 rotates from B to G in Figure 3.
In (b), it is assumed that the state is H while the head 4 similarly rotates from B to G.

Figure 5(c) shows the data reading pulse obtained from PG(a), which corresponds to one field of the video signal (1760 seconds).
The purpose is to sample a 1-diode signal every other field of an audio signal for a period corresponding to .

FIG. 5(d) shows the signal processing period, indicated by H, for adding redundant codes for error correction and changing the arrangement of the sampled audio data for one field using a RAM, etc. Figure 5 (e) shows the period of data recording as H.
, which indicates the timing at which the recording data obtained by the above-mentioned signal processing is recorded on the tape l.

For example, if we follow the flow of the signal in time using Fig. 5, t
The data sampled during the period from 1 to L3 (while head 3 is moving to B-G) is from L3 to t5 (when head 3 is moving to G-A)
Signal processing is performed at t5 to t6 (head 3 is A-B)
recorded over a period of That is, the head 3 causes C in FIG.
Recorded in the HI area. On the other hand, data sampled while PG (b) is H is signal-processed at the same timing and recorded in the CHI area by the head 4.

PG (a) at a predetermined phase (here, 36° for l region)
The phase-shifted PG is shown in FIG. 5(f).

Hereinafter, a case will be described in which an audio signal is recorded using PG (f) and a PG (not shown) having the opposite characteristics.

The data sampled from 2 to t4 in FIG.
The signal is processed according to the signal shown in FIG. 5(g) during the period from 6 to t7, and recorded according to the signal shown in FIG. 5(h) during the period from 6 to t7. That is, the head 3 causes the head 3 to
During the period of tracing C, it is recorded in the area indicated by CH2 in Figure @4. The data sampled in the period from E4 to t7 is recorded by the head 4 in the area indicated by CH2.

Next, the operation of reproducing the signal recorded in the area indicated by CH2 will be explained.

Reading of data from tape 1 by head 3 is shown in FIG.
t6 to t7 (same for ti to t2) according to the signal shown in h)
t7 to t8 (
From t2 to L3), signal processing opposite to that during recording is performed. That is, error correction and the like are performed during this period, and a reproduced audio signal is output from 8 to t9 (L3 to t6) in accordance with the signal shown in FIG. 5(j). Of course, the reproduction operation by the head 4 is performed with a phase difference of 1800 degrees from the above-mentioned operation, and thus a continuous reproduction audio signal is obtained.

Also, regarding other areas CH3 to CH6, PG (a)
Needless to say, it is sufficient to shift the phase by nX36 degrees and perform the above-mentioned recording and reproducing operation based on this, and this does not depend on the running direction of the tape.

In this way, the VTR can be used as a multi-channel audio-only device.
can be used. The problem with multi-channel audio-only equipment is that the multiple channels are divided.
It is difficult to understand the usage status of each channel.

<Object of the Invention> In view of the above-mentioned background, it is an object of the present invention to provide a rotary head type recording or reproducing device that allows the recording status of each area to be easily grasped and is extremely easy to use.

<Explanation based on examples> The present invention will be explained in detail below using examples.

FIG. 6 is a diagram showing a schematic configuration of a tape recorder as an embodiment of the present invention. Components in FIG. 6 that are similar to those in FIGS. 1 to 4 are given the same numbers.

PG obtained from the rotation detector 11 of the rotating cylinder 2 is supplied to the motor control circuit 15, which rotates the cylinder 2 at a predetermined rotational speed and a predetermined rotational phase. 12 is a rotation detector of the flywheel 14 of the capstan 13, and is supplied to the output motor control circuit 15 of the rotation detector 12.

During recording, the rotation of the capstan 13 is controlled to a predetermined speed.

On the other hand, the above-mentioned PG is supplied to the window pulse generation circuit 16 and the gate pulse generation circuit 17. FIG. 7 is a timing chart for explaining the phase relationship between the window pulse and the gate pulse with respect to PG.

FIG. 7(a) shows PG, which is at a high level while the head 3 is moving from point B to point G in FIG. Figure 7 (b
) to (g) are window pulses indicating the recording/reproducing timing of each area C)Il to CH6, respectively. In addition, in FIG. 7, the solid line is for head 3, and the dotted line is for head 4.
It is about.

By manually operating the operation unit 18, operation modes such as recording and reproduction, and areas to be recorded and reproduced are specified. Based on this data, the area designation circuit 19 supplies the area designation data to the gate pulse generation circuit 17 to obtain a desired gate pulse.

The control gate pulse of the gate circuit 20 is as follows.

The aforementioned window pulses (shown in FIGS. 7(b) to 7(g)) are selectively supplied to each of the heads 3 and 4 based on the area designation data. Now, if the area shown in FIG. 4 CH2 is designated, the gate circuit 20 is the seventh
It is controlled by the window pulse shown in Figure (C).

During recording, the analog audio signal input from the terminal 21 is sampled at the above-described timing related to the window pulse (C), converted into digital data, and then subjected to the above-described signal processing. The recording audio data thus obtained is added by an adder 24 to a tracking pilot signal generated from a pilot signal generation circuit 23 in a rotation of f1→f2→f3→f4 for each field. The output of the adder 24 is appropriately gated by the gate circuit 20 as described above, and the output of the adder 24 is gated by the gate circuit 20 as described above.
It is written in 〈.

During playback, the playback signal from the head 3.4 is similarly supplied to the low pass filter (LPF) 35 and the PCM audio circuit 22 via the gate circuit 20 using the window pulse (C).

Contrary to recording, the PCM audio circuit 22 performs signal processing such as error correction, time axis expansion, and digital-to-analog conversion, and outputs the reproduced analog audio signal to the terminal 21.
Output from a.

The LPF 25 separates the pilot signal for tracking described above and supplies it to the ATF circuit 26.

The ATF circuit 26 uses a well-known four-frequency system.

A circuit for obtaining a tracking error signal.

As is well known, the reproduced tracking pilot signal and the pilot signal generated by the pilot signal generation circuit z3 in the same rotation as during recording are used. The tracking error signal thus obtained is supplied to the motor control circuit 15, which controls the scanning of the tape 1 during playback via the capstan 13, thereby performing tracking control.

On the other hand, the gate circuit 27 is controlled by the gate pulses shown in FIGS. 7(h) and (i) outputted from the gate pulse generating circuit F. That is, a reproduction signal from an area other than the reproduction area is supplied to the area discrimination circuit 28.

The operation of this area discrimination circuit 28 will be explained below. FIG. 8 is a diagram showing a specific example of this area discrimination circuit 28, and FIG.
The figure is a timing chart for explaining the operation timing of the part shown in FIG.

In FIG. 8, 30.33 is a terminal to which the reproduction signal of the head 3.4 via the gate circuit 27 is supplied; 31.34
are terminals to which the aforementioned gate pulses (FIGS. 7(h) and (i)) are supplied, respectively.

32 is a terminal to which PG is supplied.

As is clear from the figure, the circuit configuration consists of a discrimination circuit 37 for the A head 3, a discrimination circuit 38 for the B head 4, and a decoder 47 that converts the outputs thereof from serial to parallel and outputs it as 6-bit data. Note that the 1 discrimination circuits 37 and 38 have the same configuration, so the internal details of the 1 circuit 38 will be omitted.

The operation of the area discrimination circuit 28 will be explained below. Here, for explanation, area CH2 is the reproduction area, area CHI,
It is assumed that CH4 and CH6 are recorded areas, and areas CH3 and CH5 are unrecorded areas.

The time constant of each monomulti group 42 triggered by the rising edge of PG (shown in FIG. 9(a)) is such that each output is as shown in FIG. 9(a).
It is determined as shown in e) to (+). That is, Δ
If t is a minute time (approximately X 2
e) When N is 2 or more, the core becomes +Δt (sec).

Next, six types of pulses with a constant width are obtained by the monomulti group 43 which is triggered by the falling edge of the output group of the monomulti group 42. The time constant of each of these mono-multiple groups 43 is approximately TxTSeC.This pulse (N in Figure 9)
to (q)), detection can be performed at the center position of each area. All outputs of mono multi group 43 are OR gate 44
These are supplied to the AND gate 45 as sampling pulses, while the serial signals of the decoder 47
It is also used as a clock for parallel conversion.

The AND gate 45 performs a logical product of the output of the OR gate 44 and the aforementioned gate pulse (shown in FIG. 9(C)), so that the recording status is determined only for areas other than the reproduction area.

On the other hand, the reproduced signal is supplied to the BPF 39 and is separated into the main RF multiplied signal. The output of the BPF 39 (shown in FIG. 9(q)) is detected by a detection circuit 40 and then compared with a reference voltage by a comparison circuit 41, and the output of this comparison circuit 41 is sampled by an AND gate 46. This output, that is, a signal indicating the recording status of each area, is shown in FIG. 9 (1).
This signal passes through a decoder 47 and is outputted from terminals 48 to 53 as parallel data corresponding to each area.

That is, if each area CHI-CH6 has been recorded, the terminal 48
When the output signal of ~53 is not recorded in H1, it becomes L. These parallel data are supplied to a display 29 consisting of an LED or the like, allowing the user to recognize the recording status of each area.

According to the tape recorder of the embodiment described above, the recording status of each multi-channel area can be determined at the same time.

In the above embodiment, the recording status of each area is determined during playback, but the recording status of each area can be determined in the same way whether during recording or high-speed tape feeding. Needless to say, if the magnetic tape 1 can be traced by the rotating disks 3 and 4, the recording status can be immediately determined.

DESCRIPTION OF EFFECTS> As described above, according to the present invention, it is possible to obtain a rotary head type recording or reproducing device that allows the recording status of the entire area to be immediately grasped and is extremely user-friendly for the user.

[Brief explanation of the drawing]

Figure 1 shows the tape running system of a conventional VTR, Figure 2 shows the recording locus on the magnetic tape by the VTR shown in Figure 1, and Figure 3 shows the tape running system of a multi-channel tape recorder. FIG. 4 is a diagram showing a recording locus on a magnetic tape by the tape recorder shown in FIG. 3, and FIG. 5 is a time chart of recording and reproduction by the tape recorder shown in FIG. 3. FIG. 6 is a diagram showing a schematic configuration of a tape recorder as an embodiment of the present invention. FIG. 7 is a timing chart for explaining the phase relationship of window pulses and gate pulses with respect to PC, and FIG. 8 is a diagram showing a specific example of the area discrimination circuit in FIG. 6. FIG. 9 is a timing chart for explaining the operation timing of the part shown in FIG. 1 is a magnetic tape as a recording medium, 3.4 is a rotary head, 16 is a window pulse generation circuit, 17 is a gate pulse generation circuit, 28 is an area discrimination circuit, 29 is a display device, 39
40 is a detection circuit, and 47 is a decoder.

Claims (1)

[Claims] A device that divides a tape-shaped recording medium into a plurality of regions in the longitudinal direction and records or reproduces information signals in each region using a rotating head that traces in the width direction, the RF being outputted by the rotating head A rotary head type recording or reproducing device characterized by determining the recording status of each area based on the timing of signal generation.