JPS60237685A - Digital signal reproducing method - Google Patents

Abstract

PURPOSE:To prevent absence of reproduced information by outputting a readout signal obtained the other reproduction gap as a reproduced signal when the reproduced signal drops in level. CONSTITUTION:The recording digital signal of a tape 1 produces a magnetic field corresponding to the signal at reproduction gaps 5-7 of reproducing head cores 2-4, and the magnetic field is outputted from the cores 2-4 as the readout signal, and supplied to comparators 11-13 and a switching circuit 14. If the reproducing output level from the core 2 drops in normal operation, the comparator 11 outputs a switch signal, which is detected by a switching circuit 14 to send out the reproduced output from the core 3; when the reproducing output level from the core 3 drops, the reproduced output of the core 4 is sent out.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a digital signal reproducing method for reproducing digital signals recorded on a magnetic recording medium.

(Prior Art) Recently, in response to the demand for emphasis on sound quality, digital magnetic signal reproduction systems such as digital audio tape (DAT) have been researched, developed, and are being put into practical use.

In such a system, a digital signal recorded on a magnetic recording medium is read by a magnetic head and output as a reproduced signal.

However, unlike analog signals, digital signals need to undergo processing such as sampling or quantization, so information is generally recorded on recording media at high density. Narrow width ones are also used.

For this reason, when signals are read, the gap of the magnetic head tends to become clogged due to dust, magnetic particles, etc. adhering to the recording medium, resulting in a problem that reproduced information is lost.

(Object of the Invention) The present invention has been made to solve the above problem, and it is possible to reproduce digital signals recorded on a magnetic recording medium even if the gap of the magnetic head becomes clogged. It is an object of the present invention to provide a digital signal reproducing method that can prevent information from being lost.

(Structure of the Invention) In the digital signal reproducing method of the present invention, a plurality of reproducing gaps are arranged at intervals in the direction in which recording tracks of a recording medium extend, and a plurality of reproducing gaps are provided at intervals in the direction in which a recording track of a recording medium extends, and Any one of multiple read signals
One of the read signals is outputted as a reproduced signal, and when the signal level of the reproduced signal becomes less than a predetermined value, one of the other read signals is outputted as the reproduced signal. It is something to do.

(Effects of the Invention) According to the digital signal reproducing method of the present invention, when the level of the reproduced signal decreases, the read signal read in another reproduction gap is output as the reproduced signal. Even if one playback gap becomes clogged due to dust or magnetic powder adhering to the playback gap and the signal level of the read signal decreases, the playback signal can be obtained by reading signals from other playback gaps, and there will be no missing information in the playback information. There is no risk of this occurring.

(Actual Aspects of the Invention) Hereinafter, embodiments of the digital signal reproducing method of the present invention will be described with reference to the drawings.

FIG. 1 shows a schematic diagram of a DAT (digital audio tape) playback device for implementing this embodiment. The digital signal magnetically recorded on the magnetic tape 1 moving in the direction of the arrow generates a magnetic field corresponding to the signal in the reproduction gap 5, 6.7 of the Radcore 2.3.4, and this magnetic field generates an electric field. is read by the head core 2 as a read signal.
, 3°4. The read signals are input to buffer amplifiers 8, 9.10, amplified, and sent to comparators 11.12.13 and switching circuit 14, respectively. Normally, the read signal read by the RAD core 2 for reproduction is outputted to the outside from the switching circuit 14 as a reproduction output signal. However, if the signal level of this read signal is determined to be lower than a predetermined value by the comparator 11, the comparator 11
A switching signal is sent out from the switching circuit 14, and the switching circuit 14 detects this switching signal and outputs the read signal read by the RAD core 3 to the outside from the switching circuit 14 as a reproduction output signal. If it is determined by the comparator 12 that the signal level of the read signal from the rad core 3 for this reproduction has also decreased below a predetermined value, the read signal read by the reproduction head core 4 is similarly outputted to the switching circuit 14 as a reproduction output signal. It is configured to be output externally.

The second example shows the specific version of Heradcore 2.3.4 for playback.
It is a diagram. The reproduction gap 5, 6.7 provided on the upper surface of each head core 2, 3.4 is 0.1μTrL to 0.5μ
The slits are arranged in a straight line with the same width as that of a rabbit.

Therefore, if digital signals are reproduced according to this embodiment, the reproduction gap 5 will become clogged with dust, magnetic powder, etc. adhering to the magnetic tape 1, and the read signal from the rad core 2 for reproduction will be at a predetermined level. Even in the case where the read signal from the reproducing head core 3 is outputted as a reproduction output signal, no reproduction information is lost even when the reproduction value decreases to below. Furthermore, this reproduction gap 6
Similarly, if clogging occurs, the read signal from the rad core 7 for reproduction is output as a signal for reproduction, so that no reproduction information is lost. Therefore, recorded information can be reliably reproduced even in a DAT reproducing apparatus having a small reproducing gap length and easily clogging the gap.

In the above-described embodiment, the three reproducing gear cores 2, 3.4 are provided with reproducing gears 5, 6.7, respectively.
However, instead of this, for example, as shown in FIG. 3, two reproduction gaps 16 and 17 are provided in one helad core 15, and
．． Two read signals read through 17 may be output.

Further, in the above-described embodiment, the No. 43 recording method in a DAT reproducing device has been described, but the object to which the present invention can be implemented is not limited to this, and for example, a magnetic floppy disk system or a normal size digital tape. Of course, it can also be used in a system.

Furthermore, the reproducing head for carrying out the method of the present invention may be either a rotary head or a fixed head.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an apparatus for implementing the digital signal reproducing method of the present invention, FIG. 2 is a perspective view specifically showing the reproduction head core of FIG. 1, and FIG. 3 is a reproduction head unit 1. It is a schematic diagram showing another example of (a).

Claims (1)

[Claims] The digital signal recorded on the magnetic recording medium is read by using a magnetic head means having a plurality of reproduction gaps arranged at intervals in the direction in which the track on which information is recorded, Any one of the read signals obtained from each of the plurality of gears is output, and when the signal level of the output read signal falls below a predetermined value, the read signal in which the level has decreased is detected. 1. A digital signal reproducing method characterized in that any one of the read signals other than the signal is output.