SU1522284A1 - Device for measuring oscillations of magnetic record carrier speed - Google Patents

Abstract

The invention relates to the accumulation of information, namely, devices for measuring carrier speed fluctuations. In order to improve measurement accuracy, signals are generated and compared in duration that correspond to the time the output voltage of the bandpass filter of the level spectrum analyzer exceeds the signal of the reference duration determined by the analyzer sweep speed and the width of the bandpass filter, and in the absence of a difference in durations the presence of a disturbance source with a constant disturbance frequency, and if there is a difference in durations, the presence and nature of the disturbance source with varying frequencies oh disturbance upwards or downwards. 2 Il.

Description

The invention relates to the accumulation of information, namely, devices for measuring fluctuations in the speed of movement of a magnetic recording medium.

The purpose of the invention is to increase the accuracy of measuring fluctuations in the speed of movement of a magnetic recording medium.

FIG. 1 shows one of the possible variants of the proposed device for measuring fluctuations in the speed of movement of the magnetic recording medium J in FIG. 2 - timing charts characterizing his work.

The device contains a reproducing magnetic head 1 connected through a reproduction amplifier 2 to the input of a shaper 3 of the moving speed of a measuring Magnetic waveform 4 connected by an output to the input of a spectrum analyzer 5, the output of which is connected to the first input of the recorder 6. At the same time the reproducing magnetic head 1 matches a wife with a measuring magnetic trace 4 being moved relative to her, made in the form of a magnetic recording medium with a control signal recorded on it.

The device also contains a voltage comparator 7 connected by an input to the output of the spectrum analyzer 5, a one-shot 8 and. a mismatch element 9 connected in series, a two-channel transducer 10 pulse-voltage duration and

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a signal combining element 11 connected by an output to the second input of the recorder 6. The output of the voltage comparator 7 is connected to the first input of the mismatch element 9 and to the input of the single vibrator 8. The output of the one vibrator 8 is connected to the second input of the mismatch element 9.

The operation of the proposed device for measuring fluctuations in the velocity of movement of a magnetic recording medium is as follows.

The reproducing magnetic head 1 reproduces the control signal from the measuring magnetic signal 4, the result of reproducing from the reproducing magnetic head 1 is fed through the amplifier 2 reproducing to the shaper 3 the signal of fluctuations of the moving speed of the measuring magnetic signogram 4. magnetic recordings caused by sources of disturbances in the magnetic recording apparatus. The signal of the generator 3 of the signal of oscillation of the speed of movement of the measuring magnetic trace 4 enters the spectrum analyzer 5, while in the signal at the output of the spectrum analyzer 5 the time interval for the existence of voltage carries information about. the constancy or variation of the frequency of the disturbances of the magnetic recording carrier by the sources of disturbances (Fig. 2c ()).

The signal of the spectrum analyzer 5 is fed to the first channel of the recorder 6, which draws a spectrum graph, and to the voltage comparator 7. The voltage comparator 7 compares the signal of the spectrum analyzer 5 with a threshold level. In this case, the voltage comparator 7 generates pulses (Fig. 25), mismatches arriving at element 9 and causing the leading edges of the one-shot 8. The single-shot 8 generates pulses (fng. 2), the duration of which is determined by the speed

sweep the spectrum analyzer 5 and the passband of its output filter. The pulses of the one-shot 8 arrive at a mismatch element 9, in which they are compared in duration with the pulses 1 of the voltage comparator 7. If the duration of the pulses of one-shot 8 and comparato

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The 7 voltages are equal, the mismatch element 9 does not produce a signal, which indicates the presence of a perturbation source having a constant perturbation frequency. With decreasing frequency of disturbance, the duration of the pulse of the comparator 7 voltage exceeds the duration of the pulse of one-). the vibrator 8, and the difference pulse of the mismatch element 9 is supplied to one of the channels of the two-channel converter 10, the pulse-voltage duration (Fig. 21). As the perturbation frequency increases, the pulse duration of the one-shot 8 exceeds the pulse width of the voltage comparator 7, and the difference pulse of the mismatch element 9 goes to another channel of the two-channel converter 10 pulse-voltage duration (Fig. 27.). With the converter 10, the pulse-voltage pulse duration of its first channel (Fig. 2h) and the pulses of its second channel (Fig. 2e) arrive at the combining element 11. The signal from the output of combining element 11 (FIG.) Acts on the second input of recorder 6, in which disturbances with increasing frequency are drawn with a peak of greater amplitude than disturbances with decreasing frequency.

The use of the invention, in addition to improving the accuracy of measuring fluctuations in the speed of movement of a magnetic recording medium, also makes it possible to ensure the simplicity of the process of finding sources of disturbances in a magnetic recording apparatus.

Claims (1)

Invention Formula A device for measuring fluctuations in the speed of movement of a magnetic recording medium, comprising a reproducing magnetic head connected through a reproduction amplifier to an input of an oscillator of a signal of a speed of movement of a measuring magnetic signal recording, connected by an output to the input of a spectrum analyzer, the output of which is connected. Not with the first recorder input, characterized in that, in order to improve measurement accuracy, a voltage comparator is connected to it, connected by an input to the output of the spectrum analyzer, a single vibrator and an element connected in series 51522284 mismatch, the two-channel voltage converter is connected to the first input of the mismatch element and to the input of the one-shot connected pulse width pulse - voltage and cell combining element  The wadding connected by the output to the second code with the second input of the element to the recorder's input, and the output is a coincidence.