JPH01290174A - Digital magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To detect the degradation of a recording medium in an early period by degrading a signal, which is reproduced by a re-recording amplifier and an equalizer, in an equalizer circuit. CONSTITUTION:A digital signal is recorded on a recording medium 1, for which herical scan is executed by a revolving head, and when the signal is reproduced, the C/N value of a reproducing signal, which is read from the recording medium 1, is degraded by a degrading means EQ. The error detection of the signal, which is degraded by the degrading means EQ, is executed by an error detecting means 14 and a calculated data error rate is compared with a prescribed reference value by a comparing means 20. Then, a compared result is displayed in a display means 16. Thus, the degree of the recording medium degradation can be detected in the early period without fail.

Description

DETAILED DESCRIPTION OF THE INVENTION A) Industrial Application Field The present invention relates to a digital magnetic recording and reproducing apparatus that uses, for example, a rotary head type digital audio tape recorder (hereinafter referred to as R-DAT) as a storage device for information equipment. dutto+ Conventional technology As a conventional method for detecting the degree of deterioration of a recording medium,
Japanese Unexamined Patent Publication No. 62-264482 (611B20/18
), but as shown in the block diagram in Figure 4, this publication describes how digital signals recorded on a magnetic tape are transmitted through a magnetic head and a reproduction amplifier. The data error rate calculated by the input reproduction signal processing circuit (31) is sent to the comparator ■, and if the data error rate is higher than a predetermined reference value established in the decoder country, the comparator ■ Display unit (support) via display circuit (to)
The configuration for displaying is described.

However, data error rate and tape degradation (C/N
) is a certain value [a (dB)) as shown in Figure 2.
Since the error rate rapidly increases after
B: There was a drawback that detection was difficult unless the error rate near l was equal to or higher than β.

Note that e is a value unique to the device when considering the data error rate for the entire device. Further, C in the zero bond value is a carrier (signal component), and N is noise, which indicates the ratio of carrier to noise.

ej Problems to be Solved by the Invention The present invention is intended to solve the above-mentioned problems. It makes it possible to know the deterioration of a recording medium at an early stage, to predict the timing of transferring digital data, and to make it possible to transfer the data. It is an object of the present invention to provide a digital magnetic recording/reproducing device which enables accurate porting of the data.

B) Means for Solving the Problems In a digital magnetic recording and reproducing apparatus that records digital signals on a recording medium that is helically scanned by a rotating head and reproduces the signals, the reproduction that is read from the recording medium is performed. A signal deterioration means for reducing the signal value, an error detection means for detecting errors in the signal degraded by the deterioration means, and a comparison for comparing the data error rate calculated by the means with a predetermined reference value. The configuration includes a means and a display means for displaying the results.

(e) Effect Since the signal is degraded by being reproduced from the recording medium, the degree of deterioration of the recording medium can be reliably detected at an early stage.

(F) Example Hereinafter, an example of the present invention will be described with reference to FIG. 1 of the drawings. Figure 1 shows the configuration of R-DAT, (1)
is in pressure contact with the capstan (2), and a rotating cylinder (3) has a pair of magnetic heads attached at an interval of 180°.
) is a magnetic tape that is wrapped at a predetermined angle.

A capstan motor (4) that drives the capstan (2) and a cylinder motor (5) that drives the cylinder (3) each have a capstan servo circuit (6).
) and the cylinder servo circuit (7) and are driven according to the output of the servo circuit. Similarly, both reel shafts that drive the supply reel (8) and the take-up reel (9) also have a reel motor. (1■(11) is connected, further ζ
A reel servo circuit is connected to the motor.

0J is a system control circuit, which is composed of a microcomputer, and sends and receives signals to and from the servo circuit (6) (71a2, signal processing circuit 04 described later, etc.). Operation mode commands from the operation buttons of the R-DAT are supplied to the control circuit α3), and the operation mode signals and the like are supplied to the display device 1 (top).

The circle is a signal processing circuit, and this circuit is configured to perform the following operations. During recording, digitized data is input from the data input/output terminal surface, the signal is temporarily stored in the RAM 18), an error correction signal is added, and error correction processing such as interleaving is performed at a predetermined timing. After that, the signal is output to the amplifier circuit (19). During reproduction, the signal output from the amplifier circuit (19) is input, error correction processing such as de-interleaving is performed, the digital data and the error correction signal are decoded at a predetermined timing, and the digital data is transferred to the data input/output terminal ( 171.

Note that (211 is an ATF circuit provided for tracking control, which generates a tracking signal during playback, and the tracking signal is sent to the capstan servo circuit (
6) controls the rotational speed of the capstan motor (4), and in the head of the amplifier circuit there is a switch and two magnetic heads for switching between recording or playback in response to a signal from the system control circuit (13). (2) is an equalizer circuit that shapes the signal waveform of the reproduced signal. (2) is a comparison circuit that compares the data error rate obtained by the digital signal processing circuit with a predetermined reference value of the data error rate;
The comparison result is displayed on the display device αe via the control circuit αJ. (EQ) is an equalizer circuit system ≠υ that deteriorates the frequency characteristics and reduces the zero pair in order to degrade the signal output from the equalizer circuit, and as shown in Figure 3, the C/N and error rate are In the diagram showing the related characteristics, a state in which the tape is deteriorated is electrically created by deteriorating A, as shown by the dotted line B, from the solid line A showing the actual characteristics.

According to the above configuration, the signal reproduced by the recording/reproducing amplifier αω and the equalizer ■ is passed to the third equalizer circuit (EQ).
By deteriorating as shown in the figure, when the zero value is b in the same figure, the solid line shows that the tape has not deteriorated that much and the data error rate is a value α close to el, but C/
Value β that deteriorates the N value and the data error rate
Therefore, the state before tape deterioration begins can be detected at an early stage, before tape deterioration has progressed.

Although an equalizer is used as a device for degrading a signal, the present invention is not limited to an equalizer, and a noise generator or the like may be used.

(G) Effects of the Invention According to the present invention, deterioration of a recording medium can be known at an early stage, data can be reliably transplanted, and recording of digital data on a tape can be stopped. Digital data can be extracted accurately and reliability is increased.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the magnetic recording/reproducing apparatus of the present invention, FIG. 2 is a characteristic diagram showing the relationship between the zero tension value and the data error rate, and FIG. FIG. 4 is a characteristic diagram showing the relationship between the zero value and the data error rate. FIG. 4 is a block diagram showing a conventional magnetic recording/reproducing apparatus. (EQ)... Equalizer circuit (deterioration means), ■...
Comparison circuit (comparison means), 06)...Display device (display means).

Claims (1)

[Claims] (1) In a digital magnetic recording and reproducing device that records a digital signal on a recording medium that is helically scanned by a rotating head and reproduces the signal, the C/N value of the reproduced signal read from the recording medium. an error detection means for detecting errors in the signal degraded by the deterioration means; and a comparison means for comparing the data error rate calculated by the means with a predetermined reference value;
A digital magnetic recording/reproducing apparatus characterized in that a display means for displaying the results is provided so that the deterioration state of the medium can be detected at an early stage.