SU1439676A1 - Device for inspecting magnetic disks - Google Patents

Abstract

The invention relates to electrical measuring equipment and is intended to measure the temporal shifts occurring in magnetic disks. The purpose of the invention is to improve the measurement accuracy. Divider 2 frequencies, counter 3 and multiplexer 4 from the signal of the reference generator 1 form a sequence of pulses of the limiting operating frequency OJ0101 ... These pulses, having passed through the test object 5, are distorted in duration and after forming 6 are fed to the counting input of the trigger 9, which, together with elements 10,11, reversible counter 12, controlled by divider 13, unit 14, delay element 15 and indicator 16 form a meter of the difference in time intervals of sequences of zeros and two units shortening all COROLLARY properties of the magnetic disk. The two formed time intervals are compared in a reversible counter 12, the increment accumulates over 10,100 or 1000 measurements and is displayed. 2 silt, SL

Description

Fig.}

1A39676

The invention relates to a measurement technique and is intended to measure the time shifts occurring in magnetic disks.

The aim of the invention is to increase the measurement accuracy.

Figure 1 is a structural block diagram of a device for monitoring.

Tue

2, to us

the second input of the controlled frequency divider 13,

In the device, the generator 1, divider 2, counter 3, multiplexer 4 form a pulse sequence shaper fed to a magnetic disk.

Trigger 9, elements And 10,11, re

magnetic disks; in FIG. 2, the time-IQ version counter 12 is controllable

20

25

ny diagrams of operation of the device.

The device contains a reference oscillator 1, a frequency divider 2, the first counter 3, multiplexer 4, terminals., For connecting the measured quadrupole 5, shaper 6 short pulses, second meter 7, decoder 8, trigger 9, first 10 and second

11 And elements, reversible counter 12, controlled frequency divider 13, setting knob 14 delaying element 15, indicator 16, while the output of the reference oscillator i is connected via a divider

2 frequencies with the counting input of the first

 counter 3 and directly with the counting input of the second counter 7, the informational and mass outputs of which are connected via the depigraphor 8 with the control (1, K) inputs of the trigger 9, the information JQ outputs of the first counter 3 are connected to the control inputs of the multiplexer 4, the first the information input of which is connected to the positive potential, the second information input of the multiplexer 4 is connected to the third bit of the first counter 3, and the output of the multiplexer 4 through the test quadrupole 5 is connected to the shaper b of short pulses, the output of which is connected to the counting input of the trigger 9 and the Reset input of the second counter 7, the direct and inverse outputs of the trigger 9 are connected to the correlator 13, the setpoint 14, the delay element 15 and the indicator 16 form the time difference meter.

The device works as follows,

The signal from the reference generator 1 is fed to the input of the divider 2 often. With the help of the first counter 3 and the mule of the type-4 multiplexer 4, the sequence of the pulses of the limiting operating frequency 0-1-0-1-0-1-0 ,, is formed at the input of the measured two-port network. These and pulses, having passed through the object under test, are distorted by the duration of the front edges of this pulse current and generate short pulses on the output of the driver 6, which are fed to the input of the second counter 7 by the counting input of trigger 9, while the signal from the generator 1 simultaneously enters the counter 7, and the ec signal Next, with the driver short, the decoder 8 prohibits the operation of trigger 9, i.e. trigger 9 changes state only through long (corresponding to code zero) pulses. As a result, at the output of trigger 9, a pulse sequence is formed, proportional to the zero-length zero-length sequence and 40

two units, shortened by the magnetic properties

Respectively, the first inputs of the first 10 and second 11 elements are And, the second inputs of which are connected to the reference generator 1, and the output respectively are connected to the counting inputs of the reversing counter 12, the information outputs of which are connected to the indicator 16, the forward output of the trigger 9 is additionally connected counter input controlled frequency divider 13, the output of which is connected directly to the input of the indicator 16 and through the delay element 15 to the input Reset counter 12, and the output of the setting device 14 is connected to

Q version counter 12, -controlled

0

five

,

, Q divider 13, unit 14, delay element 15 and indicator 16 form a meter for difference of time intervals.

The device works as follows

The signal from the reference oscillator 1 is fed to the input of the splitter 2 frequency. With the help of the first counter 3 and multiplexer 4 at the input of the measured quadrupole a sequence of pulses of the maximum operating frequency 0-1-0-1-0-1-0. having passed through the test object, are distorted in duration, the front edges of this pulse flow form short pulses at the output of the imaging unit 6, which arrive at the input of the second counter 7 and the counting input of the trigger 9, while the signal from the generator 1 simultaneously enters the input account ika 7, and if the signal from shaper sleduyusday 6, short, the decoder 8 disables the trigger 5 operation 9, i.e. trigger 9 changes state only through long (corresponding to code zero) pulses. As a result, at the output of trigger 9, a sequence of pulses is formed, proportional to the duration of the zero sequence, taken as zero, and the length 0

five

two units, shortened by the properties of the magnetic

information carrier. The two burden intervals formed are alternately compared in the reversing counter 12, accumulated, the difference for 10, 100 or 1000 pulse measurements is rewritten into indicator 16, the counter 12 is reset to zero and the measurements are started again.

Claims (1)

Invention Formula A device for controlling magnetic disks, containing two terminals for connecting the test object, a trigger, the direct input of which is connected to the first input of the element I, a series-connected reference generator, a counter and a decoder, an indicator, distinguished by the fact that, in order to increase accuracy, introduced a frequency divider, a second counter, a reversible counter, a shaper of short pulses, a controlled frequency divider, a setting unit, a second AND element, a multiplexer, a delay element, and the output of the reference oscillator through the sequence While the frequency divider is on, the second counter is connected to the first terminal for connecting the test object, the second terminal for connecting the test object through the short pulse shaper is connected to the input Reset the first counter and the counting input of the trigger, the I, K-input of which is connected to the output of the decoder, is inverse the trigger output is connected to the first input of the second element And, the second inputs of the first and second elements AND are combined with the counting input of the first counter, the outputs of the elements AND are respectively connected to the input s down counter whose output is connected to indicator inputs, master outputs through a series-connected controlled frequency divider, a delay element connected to the input Reset of the reversible counter, direct output the trigger is connected to the second input of a controlled frequency divider, the output of which is connected to the input. Record indicator, the first information input of the multiplexer is connected to the source of the logical unit signal, and the second output of the second counter is connected to the second information input of the multiplexer.