SU801055A1 - Magnetic signalogram reproducing aparatus - Google Patents

Description

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The invention relates to the field of magnetic recording, namely to devices for reproducing magnetic sound recordings with recording of digital data, and can be used in external magnetic storage devices.

A device is known that contains two AND circuits, three one-shot, a playback unit, an inverter, a match circuit, and three OR circuits based on the use of delays l.

 With significant fluctuations of the reproduced signal period, there is a reduction in noise immunity of the device.

The closest in technical essence to the present invention is a device comprising serially connected magnetic head, reproduction amplifier, first null-organ, element I. and the trigger input which is connected to the synchronization signal bus, and the output through the driver with the information signal bus.

The known device ensures the normal operation of the device when the edges of the reproduced are shifted

signal for a third of the duration so. 2.

When the fronts are displaced by more than one third of the tact's duration, the device leads to malfunction, and it is also sensitive to impulse noise, which also leads to erroneous operation of the device.

 The purpose of the invention is to improve the noise immunity of the device.

This goal is achieved in that a device comprising a series-connected magnetic head, a reproduction amplifier, the first null organ, an And element, and a trigger. the second input of which is connected to the synchronization signal bus, and the output through the driver to the information signal bus, are connected in series the differentiating unit, the second null organ, the trigger, the second input of which is connected with the output of the first null organ, and the element as well as serially connected blocks of sync pulses, an integration control unit and an integrator, and in addition, a third AND element connected between the second output of the second trigger and the combined second input of the integrator and the output of the second

element And, the second input of which is connected to the input of the second null-organ, while the second input of the third element And is connected to the output of the playback amplifier and to the inputs of the differentiating unit and the clock unit, the second output of which is connected to the second input of the first trigger, and the output of the integrator with the second input of the first element and

FIG. 1 shows a block diagram of the device; FIG. 2 - time diagrams {С | - at the output of the playback amplifier 1; cf - at the output of the differentiating unit 7; -in - at the exit of the zero-body 4; Z. - at the exit of the zero-organ 6; o - on a single output of the rigger 8; 6 - at one output of block 2; ok - at another output of block 2; - - at the output of integrator 9; U - at the output of the element And 10; to the output of a single trigger 11; l at the shaper output 15).

The device contains a playback amplifier 1, the output of which is connected to the unit 2 of synchronizing pulses, with one input of the element AND 3 and with the first null-organ 4 directly, and with one input of the element And 5 and the second zero-organ b through the differentiating unit 7. Outputs zero-bodies 4 and 6 are connected to the second inputs of element 3 and element 5 through trigger 8. The outputs of elements 3 and 5 are connected to the input of the integrator 9, the output of which is connected to one input of the element 10, the other input of which is connected to the output null-rgana 4. The output element And 10 Connected to one trigger input 11, the other input of which is connected to one output of a block of 2 clock pulses and the output by bus 12 of clock pulses of another output of a block of 2 clock pulses connected to the control input of the integrator 9 through the block 13 of integration control, and the output of a trigger 11 is connected to the output bus 14 cathode pulses through the imaging unit 15 pulses. The device works as follows.

 The signal amplified by amplifier 1; the signal fia (fig. 2a) receives the input of the block of synchronizing pulses 2, the input of the first nullorgan 4 and one input of element 3. The signal structure is characterized by the presence of three intervals between zero-intersections that are on a time scale in the ratio 1: 2: In addition, every two bars in the signal there is a zero-intersection. The signal differentiated by the differentiating block 7 (FIG. 2 b) is fed to the input of the second zero-organ 6 and to one input of the element AND 5. The null-organs 4 and 6 produce pulses

at the moments of transition of the amplified and differentiated signals through the zero level. The pulses from the outputs of the zero-organs 4 (Fig.2-6) and 6 (Fig.2 control the operation of the trigger 8, which in turn (Fig.29) opens the element And 3 or element And 5, and the input of the integrator 9 enters or a signal amplified by amplifier 2 or a signal differentiated by differentiating block 7. Block 2 of clock pulses produces clock pulses (Fig. 26), which are fed to the output bus 12 of clock pulses and to zero input of trigger 11. In addition, block 2 produces pulses with following frequencies half the synchronization frequency pulses (Fig. 2) ":), which are fed to the input of the integration control unit 13. In accordance with the command of block 13, the integrator integrates the input signal for two periods of the carrier, frequency (Fig. 2), which is fed to one input of the AND 1 PULSE element from the output of the zero-organ 4, corresponding to the SIGNS 1, and passes through the AND 10 element (Fig. 2 "-) and set the trigger 11 to one state (Fig. 2k). The trigger 11 is set to the zero state by synchronization with a pulse. The feed 15 from the trailing edge of the trigger pulse generates code pulses (FIG. 2L), which are fed to the output bus 14 of code pulses.

In contrast to the known, the proposed device is insensitive to impulse noise, in addition, it ensures normal operation even when the zero-level transitions are shifted by more than a third of the tact duration, which also increases the noise immunity.

Claims (2)

Invention Formula A device for reproducing a magnetic waveform containing serially connected magnetic head, reproduction amplifier, first null organ, And element and trigger, the second input of which is connected to the synchronization signal bus, and the output — through the shaper with the information signal bus , in order to improve the noise immunity of the device, a serially connected differentiating unit is inserted into it, the second null organ, a trigger, the second input of which is connected to the output of the first null organ, and the And element, and akzhe serially connected clock unit, the control unit integration and an integrator and, in addition, a third And element included between the second output, the second trigger and the combined second input of the integrator and the output of the second And element, the second input of which is connected to the input of the second null organ, the second input of the third And element connected to output of the playback amplifier and with the inputs of the differentiating unit and the clock unit, the second output of which is connected to the second input of the first trigger, and the integrator output is connected to the second the entrance of the first element I. Sources of information taken into account during the examination 1. USSR author's certificate  570086, cl. 6 11 May 5/09, 13.01.75. 2. USSR author's certificate  570087, class G 11 B 5 / 09,12.04.76 (prototype),  one yy