SU1157567A1 - Device for reproducing signals from magnetic records - Google Patents

Abstract

A MAGNET RECORDING SIGNAL PLAYBACK DEVICE containing a playback head, a signal conditioner connected to the playback head, the first counter whose setup input is connected to the output of the imager, the decoder whose inputs are connected to the counter outputs, the first and second And elements, the first inputs of which are connected to the output and the second outputs of the decoder, and the second - with the output of the imager, the OR element, the inputs of which are connected to the outputs of the first and second elements AND, the signal bus connected to The first output of the decoder, the clock bus connected to the output of the OR element, the first trigger connected by the input to the output of the driver, the generator and the third element AND whose inputs are connected to the output of the trigger and to the output of the generator, respectively, characterized in that, in order to increase the reliability of playback , it is equipped with a second trigger, a delay line and an additional counter connected in series, a register, a multiplier and a subtraction unit, with the additional counter input and one block input The readings are connected to the output of the third element, And the output of the subtraction unit is connected to the control input of the multiplier and to the input of the first counter, the input of the delay line and one of the control inputs of the register are connected to the clock bus, the second control input of the register is connected to the output of the second trigger The separate inputs of which are connected to the output of the delay line and to the separate output of the second counter, respectively. SD SL O5 |

Description

The invention relates to a magnetic recording technique, namely, a device for playing discrete data.

A reproduction apparatus is known comprising a magnetic head, a stop, a trigger, a one-shot, a matching circuit, and a driver 1.

The closest to the invention in technical essence and the achieved result is a playback device comprising a playback head, a signal conditioner connected to the playback head, the first counter, the setup input of which is connected to the output of the imager, the descrambler whose inputs are connected to the counter outputs, the first and second elements And, the first inputs of which are connected with the first and second outputs of the decoder, and the second - with the output of the imager, the OR element, whose inputs are connected from the output The first and second elements AND, the signal bar connected to the first output of the descrambler, the clock pulse bus connected to the output of the OR element, the first trigger connected by the input to the output of the imager, the generator and the third element AND whose inputs are connected to the output of the trigger and to the generator output respectively 2.

Due to the inconsistency of the pulse duration of the one-vibrator with the duration of the reproduced signal, variations in the speed of the carrier in known devices may cause playback failure.

The purpose of the invention: - increase the reliability of reproduction.

The goal is achieved by the fact that the device of reproduction of magnetic recording signals containing a playback head, a signal shaper connected to the playback head, the first counter, the setup input of which is connected to the output of the imager, the decoder, the inputs of which are connected to the outputs of the counter, the first and second elements And, the first inputs of which are connected to the first and second outputs of the decoder, and the second - with the output of the imager, the element OR, the inputs of which are connected to the outputs of the first and second element And, the signal bus connected to the first output of the decoder, the clock bus connected to the output of the OR element, the first trigger connected to the output of the driver, the generator and the third element And whose inputs are connected to the output of the trigger and to the output of the generator, respectively, is equipped with a second trigger, delay line and serially connected by an additional counter, register, multiplier and subtraction unit; the input of the additional counter and one input of the subtraction unit are connected to the output of the third element And that, the subtraction unit output is connected to a control input of the multiplier and to an input of the first counter, the input of the delay line and one of the actuating input register connected to a bus clock, a second control input coupled to the register

the output of the second trigger, the separate inputs of which are connected to the output of the delay line and to the separate output of the second counter, respectively.

FIG. 1 shows a block diagram of the proposed device; in fig. 2 - timing diagrams for the operation of the device.

The device contains an input bus 1, a driver 2, a counter 3, elements AND 4-6, a trigger 7, a defogger 8, a generator 9, an element OR 10, an output signal bar 11 signals, a bar 12 clock pulses and a pulse frequency correction unit 13, made in the form of a counter 14, register 15, multiplier 16, subtraction block 17, trigger 18 and line 19

Q delay.

The device works as follows.

The input of the imager 2 from the output bus 1 receives the reproduced signal (Fig. 2a). The shaper 2 generates pulses corresponding to the fronts of the input signal (Fig. 26), which are fed to the inputs of the AND 4 and 5 elements and the installation inputs of the counters 3 and 14. The first pulse from the shaper 2 sets the trigger 7 to a state where the output opens the element And 6, in this case, the pulses from the output of the generator 9 post.upay on the counting input of the counter 14.

The capacity A of the counter 14 is selected from the conditions:

A 4 2TomnRdlin; 2A 2T (fHaRc ROLL,

 - minimal and maximal Tonax. the duration of the separation

tact;

0 FoMKHH is the minimum and maximum Gojax frequency of the generator 9. Under the condition of Tokais, Tdzi, the trigger 18 is set to one state only when the separation interval is filled with pulses 5, thereby allowing the code 15 from the counter 14 to write to the register. the numbers are fed to the control inputs of the multiplier 16. After the pulses in block 17 are subtracted, counter 3 is fed to the counting input of pulses with the following frequency F- -

- The number of pulses N filling counter 3 over the clock period, To, does not depend on the frequency instability of the generator and the speed of the carrier

“/ TVTo 4.

At the same time, from the output of the decoder 8, the sync pulse passes through the AND 4 element and the OR 10 element to the 12 sync pulse bus (Fig. 2c and e) or through the And 5 element and the OR 10 element on

Bus 12 sync pulses (Fig. 2 g and e). The reset of the flush trigger 18 is turned off by the synchronization pulses delayed by the delay line 19 for the time required to write information to the register 15.

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Claims (1)

MAGNETIC RECORDING SIGNAL REPLACEMENT DEVICE, comprising a playback head, a signal shaper connected to the playback head, a first counter, a setup input of which is connected to a shaper output, a decoder whose inputs are connected to the counter outputs, the first and second AND elements, the first inputs of which are connected to the first and -the second outputs of the decoder, and the second with the output of the shaper, an OR element, the inputs of which are connected to the outputs of the first and second AND elements, a signal bus connected to the first at the output of the decoder, the clock bus connected to the output of the OR element, the first trigger connected to the input to the output of the driver, the generator and the third element AND, the inputs of which are connected to the output of the trigger and to the output of the generator, respectively, characterized in that, in order to increase the reliability of playback , it is equipped with a second trigger, a delay line and sequentially connected an additional counter, register, multiplier and subtraction unit, while the input of the additional counter and one input of the subtraction unit with are single with the output of the third element AND, the output of the subtraction unit is connected § to the control input of the multiplier and to the input of the first counter, the input of the delay line and one of the control inputs of the register are connected to the clock bus, the second control input of the register is connected to the output of the second trigger, the separate inputs of which are connected with the output of the delay line and with a separate output of the second counter, respectively. SU-. " 1157567