JPH04364201A - Magnetic recording method and recorded magnetic tape - Google Patents

Abstract

PURPOSE:To enable to reproduce each optional program with the existing device when a tape simultaneously recorded plural programs is reproduced. CONSTITUTION:A first head 1 and a second head 2 of a pair of inverse azimuths and a third head 3 and a fourth head 4 of a pair of inverse azimuths are provided in the diameter direction of a rotary drum D and also the first and third heads and the second and fourth heads respectively with the same azimuth record on the separate tracks respectively with the first and second heads 1, 2 and the third and fourth heads 3, 4.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording method and a recorded magnetic tape in which a plurality of programs can be simultaneously recorded on a tape using a helical scanning method and can be reproduced by an existing magnetic recording/reproducing device.

0002

2. Description of the Related Art Conventionally, magnetic recording and reproducing apparatuses that simultaneously record two programs on a tape using a helical scanning method have been disclosed in Japanese Patent Application Laid-open No. 59-104703 and Japanese Patent Application Laid-Open No. 62-1989.
There is one described in Japanese Patent No. 57104.

The apparatus described in Japanese Patent Application Laid-Open No. 59-104703 has a rotating drum 100 as shown in FIGS. 8 and 9.
a pair of first and second heads 10 with opposite azimuths in the diametrical direction of the
1, 102 and a pair of reverse azimuth third and fourth heads 10
The first and third heads 101 and 103 and the second and fourth heads 102 and 104 are provided with reverse azimuths, respectively, and one program A1 and A2 is provided as shown in FIG.
is recorded by the first and second heads 101 and 102,
The other programs B1 and B2 are sequentially recorded by the third and fourth heads 103 and 104.

Further, as shown in FIG. 11, the content disclosed in Japanese Patent Application Laid-Open No. 62-57104 is that, as shown in FIG.
Two programs are recorded within pitch width F or E. Note that the pitch width F=E.

[0005]

[Problems to be Solved by the Invention] However, when a magnetic tape recorded with the magnetic recording/reproducing apparatus disclosed in Japanese Patent Application Laid-Open No. 59-104703 is reproduced with a two-head magnetic recording/reproducing apparatus, the tracks shown in FIG. A1, B2, A
1... or B1, A2, B1, etc., regardless of the trace pattern, another program is played back, resulting in incompatibility.

[0006] Furthermore, when trying to reproduce a recording pattern such as that described in Japanese Patent Application Laid-Open No. 62-57104 using a magnetic head of normal width, if track F is traced, A1 and B1 and A2 and B2 are the same. Because the programs differ in azimuth, the screen appears to be composited. On the other hand, if track E is traced, different programs will be alternately reproduced, such as A1, B2, . . . or A2, B1, . . .

[0007]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention provides a pair of reverse azimuth first and second heads and a pair of reverse azimuth third and fourth heads in the diametrical direction of a rotating drum.
The first and third heads and the second and fourth heads each have the same azimuth, and the first and second heads and the third and fourth heads alternately record on separate tracks. .

[0008]

[Operation] Each program is recorded in reverse azimuth by the first head, second head, and third and fourth heads, and by shifting the trace by a half pattern, another program will be recorded in reverse azimuth, so each program can be played back. .

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic diagram of a head section of a magnetic recording/reproducing apparatus that implements the method of the present invention, FIG. 2 is an explanatory diagram of the head gap of the head section, FIG. 3 is a schematic diagram of a tape pattern by the same head section, and FIG. 4 is a schematic diagram of the head section FIG. 5 is another schematic diagram of a tape pattern, FIG. 6 is a diagram schematically showing the electrical system of a magnetic recording and reproducing apparatus that implements the method of the present invention, and FIG. 7 is a diagram showing a recorded magnetic tape according to the present invention. FIG. 2 is an explanatory diagram when reproducing information using a conventional magnetic recording/reproducing device.

In the diametrical direction of the rotating drum D, as shown in FIGS. 1 and 2, there are a pair of opposite azimuth first and second heads 1 and 2, a pair of opposite azimuth third and fourth heads 3, 4
are provided in a 90° positional relationship, and the first and third heads 1
, 3 and the second and fourth heads 2 and 4 have the same azimuth, and the first and second heads 1 and 2 and the third and fourth heads 3 and 4 record as separate tracks, respectively. Note that, as shown in FIG. 4, the first head 1 and the third head 3, and the second head 2 and the fourth head 4 may be arranged close to each other. In addition, the first head 1 and the second head 2 are
The head 3 and the fourth head 4 can also be arranged close to each other.

That is, as shown in FIGS. 3 and 6, the signal from the input terminal IN1 is transmitted through the switch SW1, the recording signal processing circuit, and the switch SW3, and the program A is applied to the track A1 by the first head 1, and the program A is applied to the track A1 by the first head 1. 2, record program A on track A2, and transfer the signal from input terminal IN2 to switch SW2, the recording signal processing circuit, and switch SW.
4, program B is sent to track B1 by the third head 3.
The fourth head 4 records program B on track B2.

For example, the basic recording method is the consumer V
In the case of the VHS system generally used in TR, two tracks for each program A and B are formed within a track pitch of 58 μm as shown in FIG.

Here, since the first head 1 and the third head 3 and the second head 2 and the fourth head 4 have the same azimuth, the guard band GB is provided with a width of, for example, 10 μm to avoid crosstalk. ing. Further, since the fourth head 4 and the first head 1, and the third head 3 and the second head 2 have opposite azimuths, either no guard band is provided or a narrow guard band as shown in FIG. 5 is provided.

As shown in FIG. 6, this magnetic recording/reproducing device requires two systems of video processing circuits, and the first head 1
A frame synchronizer FS is provided which shifts the signal by the amount of the positional deviation of each pair of the third head 3, the second head 2, and the fourth head 4 by the amount of the deviation.

On the other hand, in the reproduction system, the reproduction signal A from the first head 1 and the second head 2 is transmitted to a playback amplifier,
It is output from OUT1 via a playback signal processing circuit, and simultaneously and independently from the playback of signal A, playback signal B from the third head 3 and fourth head 4 is output via a playback amplifier and a playback signal processing circuit to OUT2. Further, by operating the switch SW5, one of the signals A and B is selected and output from the SELECT OUT.

When a videotape on which two programs A and B are recorded in this manner is played back in SP mode using a conventional magnetic recording/playback device, tracing (tracking)
By shifting the half pattern, the different programs will have the opposite azimuth, so each program can be played individually. That is, when the tracing position of the head is adjusted (tracking adjustment) to the position shown by the solid line in FIG. 7 and reproduced, tracks A1 and A2 have the same azimuth as the head.
Tracks B1 and B that play back only the ... side and have reverse azimuth
Since the tracks A1, A2, and so on are not reproduced, program A recorded on the tracks A1, A2, and so on is reproduced. Also, if the trace position of the head is shifted by a half pattern and adjusted (tracking adjustment) to the position shown by the broken line in FIG. Since tracks A1, A2, . . . are not reproduced, program A recorded on tracks B1, B2, . . . is reproduced. In this way, the above magnetic tape can be used in conjunction with any type of VTR without any special measures (they are compatible).

[0017]

[Effects of the Invention] As explained above, according to the present invention,
A pair of opposite azimuths in the diametrical direction of the rotating drum.
A head and a pair of third and fourth heads with opposite azimuths are provided, the first and third heads and the second and fourth heads respectively have the same azimuth, and the first and second heads and the third and fourth heads have the same azimuth. Since each track is recorded alternately as a separate track,
By shifting the trace by a half pattern during SP mode reproduction, each program can be reproduced. Furthermore, although two programs are recorded on the magnetic recording tape produced by this method, it is not possible to selectively reproduce the video signal of the desired program using an existing magnetic recording/reproducing device as in the past. can.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a head section of a magnetic recording/reproducing device according to the present invention.

[Figure 2] Head gap explanatory diagram of the same head section

[Figure 3] Schematic diagram of the tape pattern by the head section

[Figure 4] Other schematic diagram of the head part

[Figure 5] Other schematic diagram of tape pattern

[Figure 6] Diagram showing the outline of the electrical system

FIG. 7 is an explanatory diagram when a recorded magnetic tape according to the present invention is reproduced by a conventional magnetic recording and reproducing device.

[Fig. 8] Schematic diagram of a head section of a conventional magnetic recording/reproducing device

[
Figure 9: Head gap explanatory diagram of the same head part

[Figure 10] Schematic diagram of the tape pattern by the head section

[Figure 11] Another schematic diagram of a conventional tape pattern

[Explanation of symbols]

1...First head, 2...Second head, 3...Third head, 4
...Fourth head, D...Rotating drum.

Claims (2)

[Claims] 1. A magnetic recording method for simultaneously recording a plurality of programs using a helical scanning method, comprising: a pair of first and second heads with opposite azimuths and a pair of third and fourth heads with opposite azimuths in the diametrical direction of a rotating drum. and the first,
A magnetic recording method characterized in that the third head and the second and fourth heads have the same azimuth, and the first and second heads and the third and fourth heads alternately record on the tape as separate tracks. . [Claim 2] A first of a pair of reverse azimuths on a rotating drum.
, a second head and a pair of third and fourth heads with opposite azimuths, the first and third heads and the second and fourth heads have the same azimuth, respectively, and the first and second heads and the third and fourth heads have the same azimuth.
A recorded magnetic tape on which a first signal and a second signal are alternately recorded on separate tracks by a head.