JPH09138991A - Magnetic recording and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically correct ununiformity of head attaching positions. SOLUTION: In this magnetic recording and reproducing device, a phase difference ΔTpg between the head changeover signal S1a formed in a head changeover signal output control part 103 and the vertical synchronizing signal S1c inputted from a magnetic head being in reproducing (which is not shown in the figure) to a microprocessor 101 is measured in a phase difference measurement processing part 104 and then the difference T with a prescribed value Tpg ref is obtained. Then, a control is executed so that the phase difference ΔTpg with the vertical synchronizing signal S1c becomes the prescribed value Tpg ref by correcting the head changeover signal S1a with the head changeover signal output control part 103 by the difference T.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording / reproducing apparatus for correcting variations in head mounting position.

[0002]

2. Description of the Related Art A head mounting position for aligning a writing position of a vertical synchronizing signal on a tape with the VHS standard at the time of recording by a conventional magnetic recording / reproducing apparatus and a reproducing timing of a vertical synchronizing signal at a predetermined position at the time of reproducing. A mechanism for electrically correcting variations was added.

A conventional mechanism for electrically correcting variations in head mounting position will be described below with reference to the drawings.

FIG. 2 is a schematic diagram showing a VHS format video signal field track, and FIG. 3 is a block diagram showing the configuration of a conventional magnetic recording / reproducing apparatus. In FIG.
Reference numeral 101 is a microprocessor, and 102 is a head switching signal adjusting unit capable of manually controlling the phases of the head switching signal S1a and the vertical synchronizing signal S1c, and outputs a control signal S1b to the microprocessor 101. Reference numeral 103 denotes a head switching signal output controller provided in the microprocessor 101, which outputs the head switching signal S1a from the control signal S1b.

The operation of the conventional magnetic recording / reproducing apparatus configured as described above will be described below.

First, in the VHS format video signal field track of FIG. 2, L azimuth fields and R azimuth fields having two different azimuth angles are alternately recorded, and a vertical synchronizing signal is recorded at a predetermined position in the fields. Has been done.

Next, a conventional method for correcting the variation in the mounting position of the video head will be described with reference to FIGS. In the VHS standard, the position of the vertical synchronizing signal in the video signal is determined, and in order to satisfy the standard, the vertical synchronizing signal S1c reproduced by a magnetic tape (not shown) is input to the head switching signal output control unit 103. . Here, when the phase difference between the head switching signal S1a and the vertical synchronizing signal S1c is not a predetermined value, the head switching signal adjusting unit 102
The phase difference is adjusted to a predetermined value, and the head switching signal S1
Output a.

[0008]

However, in the conventional configuration, the head switching signal adjusting section 1 is used to set the phase difference between the vertical synchronizing signal S1c and the head switching signal S1a to a predetermined value.
Since it was manually adjusted using 02, there was a problem that it was very complicated.

The present invention solves the above-mentioned problems of the prior art. It is possible to automatically set the phase difference between the vertical synchronizing signal and the head switching signal to a predetermined value, and correct the variation in the mounting position of the video head. An object is to provide a recording / reproducing device.

[0010]

In order to solve the above problems, a magnetic recording / reproducing apparatus of the present invention outputs a head switching signal for switching a plurality of magnetic heads having different azimuth angles when reproducing a magnetic tape. Phase difference measurement processing for detecting the phase difference between the switching signal output control section and the head switching signal output from the head switching signal output control section and the vertical synchronizing signal reproduced by the magnetic head, and controlling the head switching signal output processing section And a section.

With this configuration, it is possible to obtain a magnetic recording / reproducing apparatus capable of automatically setting the phase difference between the vertical synchronizing signal and the head switching signal to a predetermined value to correct the variation in the mounting position of the video head.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claims 1 and 2 of the present invention is head switching signal output control for outputting a head switching signal for switching a plurality of magnetic heads having different azimuth angles when reproducing a magnetic tape. Phase difference measurement processing for detecting the phase difference between the head switching signal output from the head switching signal output control section and the vertical synchronizing signal reproduced by the magnetic head and controlling the head switching signal output control section. And has a function of automatically setting the phase difference between the vertical synchronizing signal and the head switching signal to a predetermined value.

An embodiment of a magnetic recording / reproducing apparatus of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 (a) is a block diagram in the present embodiment 1, and FIG. 1 (b) is a waveform diagram of a vertical synchronizing signal and a head switching signal in the embodiment.
In FIG. 1, 101 is a microprocessor, and 103 is a head switching signal output controller provided in the microprocessor 101, which outputs a head switching signal S1a. 1
Reference numeral 04 denotes a phase difference measurement processing unit that compares the phase of the head switching signal S1a output from the head switching signal output control unit 103 and the vertical synchronization signal S1c.

The operation of the present embodiment configured as described above will be described below.

The phase difference ΔTpg between the head switching signal S1a generated by the head switching signal output control unit 103 and the vertical synchronizing signal S1c input to the microprocessor 101 from the magnetic tape (not shown) being reproduced is determined. It is measured by the phase difference measurement processing unit 104, and the difference T from the predetermined value Tpg_ref is obtained.

[0017]

(Equation 1)

Then, the head switching signal output control unit 103 corrects the head switching signal S1a by the difference T, and the phase difference ΔTpg from the vertical synchronizing signal S1c is a predetermined value Tpg_r.
Control to be ef.

As described above, according to the present embodiment, the phase difference measurement processing unit 104 detects the phase difference between the vertical synchronizing signal S1c and the head switching signal S1a, and the phase switching signal output control unit 103 receives the phase difference. Is controlled to a predetermined value, the phase difference can be automatically set to a predetermined value.

[0020]

As described above, according to the present invention, it is possible to automatically correct the variation in the mounting position of the video head.

[Brief description of the drawings]

FIG. 1A is a block diagram of a magnetic recording / reproducing apparatus according to a first embodiment of the present invention. FIG. 1B is a characteristic diagram of a vertical synchronizing signal and a head switching signal according to the first embodiment.

FIG. 2 is a schematic diagram showing a VHS format video signal field track.

FIG. 3 is a block diagram of a conventional magnetic recording / reproducing apparatus.

[Explanation of symbols]

 103 Head Switching Signal Output Control Unit 104 Phase Difference Measurement Processing Unit

Claims (2)

[Claims] 1. A head switching signal output control unit for outputting a head switching signal for switching a plurality of magnetic heads having different azimuth angles when reproducing a magnetic tape, and the head output from the head switching signal output control unit. A magnetic recording / reproducing apparatus comprising: a phase difference measurement processing unit that detects a phase difference between a switching signal and a vertical synchronizing signal reproduced by the magnetic head and controls the head switching signal output control unit. 2. A head switching signal for switching a plurality of magnetic heads having mutually different azimuth angles when reproducing a magnetic tape, and a phase difference between the head switching signal and a reproduced vertical synchronizing signal is detected to detect the position. A magnetic recording / reproducing apparatus, wherein the head switching signal is output based on the phase difference, and the phase difference is controlled to a predetermined value.