SU1365118A1 - Device for double-channel reproduction of block digital information - Google Patents

Abstract

The invention relates to instrumentation. The purpose of the invention is to increase the fidelity of reproduction. When the playback signal drops out, the trigger 15 detects the presence of a pause signal, the trigger 22 remains in the information playback state, since the recalculation unit 21 does not work. The decoder 12 continues to produce a pulse with a clock frequency delayed by half a beat. The first of them overturns the trigger 15, and the device continues to generate code and clock pulses according to the state of the flip-flops 5 until a reproduced signal appears from the outputs of the drivers of the 3 pulses. 1 il. (L with Oi eaten oo

Description

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The invention relates to instrumentation and can be used in the construction of playback devices previously recorded on magnetic digital media.

The purpose of the invention is to increase the fidelity of reproduction.

The drawing shows a block diagram of the device.

A device for two-channel reproduction of block digital information contains (FIG. 1) serially connected magnetic heads 1 of reproduction, amplifiers

2plays and shapers

3 pulses, separate outputs of which are connected to the first element

OR 4 and to the separate inputs of the first two triggers 5. The outputs of the triggers 5 are connected through the first 6 and second 7 elements AND to the second element OR 8 The generator 9 reference pulses are connected to the counting inputs of the first 10 and second 11 counters, outputs connected to decoders 12 and 13 the output of the last one through the third element OR 14 and the third trigger 15 is connected to the first input of the fourth element AND 16, the second input connected to the output of the decoder 12, with the first inputs of the fifth 17 and sixth 18 elements AND, with the first separate inputs of the third 15 and fourth 19 triggers, the second separate input of the latter is connected to the output of the first element OR 4, and the output through the pulse shaper 20 is connected to the inputs of counters 10 and 11. The second inputs of the elements 17 and 18 are connected to the second output of the trigger 15, the first separate input of which connected to the installation input unit 21 conversion and through the element 14 to the first input of the fifth trigger 22, the second output of which is connected to the third inputs of the elements 17 and 18 the first input of the trigger 22 is connected to the bus 23 synchronization and output element 16. The element output And 18 h The third element OR 24 is cut to the input of the recalculation unit 21 and the shift register input 25, whose information input is connected directly to the output of the AND 17 element and the input of the OR 24 element, and the outputs to the information bus 26. The output of the OR 8 element is connected to the fourth entrances

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elements And 17 and 18 respectively

through the inverter 27 and directly.

The device works as follows.

The reproduction of the previously recorded information is carried out by magnetic reproduction heads 1, the output signals of which are amplified by reproduction amplifiers 2. The shaper 3 generates pulses in the places of peak values of the input voltages and outputs pulses to separate outputs depending on the direction of change of the magnetization on parallel tracks of the carrier (not shown). Therefore, the first two triggers 5 are repeated in shape from the output signal of a change in the carrier magnetization during a recording made earlier according to which the binary unit is the in-phase state of magnetization on parallel tracks during one recording period, zero-phase, and an active pause signal by changing the magnetization parallel tracks with reduced, for example, twice the frequency. The pulses from the outputs of the formers 2 are assembled by the first element OR 4, and the first of the possible pair of pulses overturns the trigger 19. The former 20 generates a pulse that sets the counters 10 and 11 of the pulses to their original states. The counters 10 and 11 continue to count the reference pulses of the generator 9. The decoder 12 connected to the counter 10 outputs a pulse when the counter code 10 reaches a value corresponding to half of the clock information playback period, and the decoder 13 when the counter code 11 reaches a value corresponding to 11 / 2 clock period. Therefore, when the pause signal is played, the pulse of the decoder 13 passes by the signal of the first trigger 22, which is set to one state by the pulse of the conversion unit 21 when playing the previous block of information, the third element 14 and reverses the third trigger 15. The next output pulse of the decoder 12 passes the fourth element is AND 16 and returns the triggers 15 and 22 to the state corresponding to the reproduction of the information block.

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The states of the triggers 5 are decrypted by the first 6 and second 7 elements L and the element OR 8, at the output of the last of which appears resolvable

signal at opposite states of triggers 5, i.e. during the reproduction of the signal zero. Therefore, the element And 18 emits a pulse when a pulse arrives at its second input from the output of the decoder 12 when the signal is reproduced zero, and the element 17 causes a pulse when playing the signal of one. The pulses from the output of the element And 17 are fed to the information input of the register 25, to the shift input of which pulses are fed from the elements 18 and 17 through the element OR 2A. After the block 21 recalculates a specified number of input pulses corresponding to the number of bits of the information block, its output pulse is fed to the synchronization bus 23, which contributes to the synchronization of code reception from the information bus 26, and flips the trigger 22, thereby preparing the device for reproducing the subsequent signal pause.

The device does not lose work synchronization when the playback signal falls out. In such cases, the trigger 15 detects the presence of a pause signal, but the fifth trigger 22 remains in the information playback state (since the recalculation unit 21 did not trigger). The decoder 12 continues to produce a pulse with a clock frequency delayed by half a beat. The first of them overturns the trigger 15, and the device continues to overload the code and clock pulses according to the state of the flip-flops 5 until a reproduced signal appears from the outputs of the formers of 3 pulses

Claims (1)

The use of the proposed device for two-channel reproduction of block digital information allows to increase the speed and noise immunity of reproduction of block digital information from magnetic media. Invention Formula A device for two-channel playback of digital block information 18 formations containing serially connected playback heads, amplifiers, pulse shapers, the outputs of which are connected to the inputs of the first OR element and to the separate inputs of the first and second triggers, the outputs of which through the first and second elements AND are connected to the inputs of the second element OR sequentially connected to the third element And, the third trigger and the fourth element And, the conversion unit, the input of which through the third element OR and the fifth element AND is connected to the output of the inverter, the third pulse shaper, the sixth element And the fourth and fifth triggers, the information bus and the synchronization bus, characterized in that, in order to increase the fidelity of reproduction, two decoders, two counters, a generator of reference pulses, the output of which is connected to the counter inputs of the counters, are entered, the output register connected by an output to information bus, while the input of the first counter is connected via the third pulse shaper to the output of the fourth trigger, the first separate input connected to the output of the first OR element and in series The second counter, the second decoder, the third element I - with the installation input of the conversion unit, the output of which is connected to the synchronization bus and the first separate input of the fifth trigger connected by the first output to the second input of the third element And the output of the first counter is connected to the second separate inputs the third and fourth triggers, the second input of the fourth element And with the first inputs of the fifth and sixth elements And, the second inputs of which are connected to the second output of the third trigger, and the third inputs to the second output n In addition, the second input connected to the output of the fourth element AND, the information input of the shift register is connected to the output of the fifth element AND, and the input of the shift through the third element OR and the sixth element AND to the input of the inverter and the output of the second element OR.