SU909685A1 - Device for recording and reproducing digital data from magnetic media - Google Patents

Description

(54) DEVICE FOR RECORDING AND PLAYBACK

DIGITAL INFORMATION ON A MAGNETIC MEDIA: TE

one

The invention relates to magnetic recording, in particular, devices for recording and reproducing digital information on magnetic media.

A device for recording and reproducing digital information on magnetic media is known, comprising input buses, a recording pulse generator, a recording amplifier and a magnetic recording head connected to its output, the input buses and a recording pulse generator connected to the inputs of a recording amplifier, a magnetic playback head connected through series-connected playback amplifier; analog-to-digital converter to output buses; l.

A disadvantage of the known device is the low information density of recording and reproducing digital information on magnetic media.

The closest in technical essence to the present invention is a device for recording and reproducing digital information on a magnetic carrier, containing input buses connected via serially connected input register, digital-analog converter, frequency modulator and recording amplifier to a magnetic recording head, generator

10 recording pulses connected to a frequency modulator, a magnetic reproduction head connected through a sequentially connected reproduction amplifier, a frequency de15 modulator, and an analog-to-digital converter to the output buses 123.

However, the device has a low fidelity of reproducing digital information from magnetic media.

20

Claims (2)

The purpose of the invention is to showcase the reproduction of digital information with increasing information recording density. This man can be achieved by introducing into the device for recording and reproducing digital information in a magnetic medium a register, subtractor, a second digital signal, a log converter and a counting pulse generator, the output of which is connected to the input of the control unit and to the first counter input, and A control for the output of an analog-digital converter is given by a control input of a register and through a serially connected counter, register subtractor and a second digital-analog converter - with a reference input of analog-cy 4-converter, irichem second inputs of the subtractor are connected to the second input buses. The drawing shows a structural electrical circuit of a device for recording and reproducing digital information on magnetic media. The device contains the first input bus I, input register 2, the first digital-to-analog converter 3, the amplitude modulator 4 and the recording amplifier 5, the magnetic recording head 6, the control unit 7, the recording pulse generator 8, the magnetic playback head 9, , analog-to-digital converter 11, output buses 12, counter 13, register 14, subtractor 15, second digital-to-analog converter 16 and generator I7 pulse counter and second input buses 18. The device works as follows. In the digital information recording mode, the signal from the output buses 1 goes to the input register 2, then is converted by the first digital-to-analog converter 3 to the voltage that goes to the first input-amplitude modulator 4, to the second input of which are received pulses from the generator 8 write pulses. Modulated in amplitude recording pulses through the recording amplifier 5 are fed to the magnetic recording head 6. Thus, multi-level pulses are recorded on magnetic media, each of which carries information of more than one bit on one clock interval. In the playback mode, multilevel pulses from the output of the magnetic playback head 9 through the reproduction amplifier are connected to the input of the analog-digital converter 11, the output of which produces a digital signal corresponding to the signal on the input buses 1, and this digital signal is fed to the output buses 12. When changing the amplitude of a multilevel pulse caused by a change in the speed of movement of the magnetic carrier, a corresponding change in voltage is made at the reference input 20 of the analog-digital converter 11 as follows. The counter 13, using signals from the control output 19 of the analog-digital converter, counts the pulses from the generator output 17 counting pulses, the result of counting using the signals from the control output 19 of the analog-digital converter I c. the register 14, and in the register 14 is stored a code of a number proportional to the repetition period of the reproduction pulses from the output of the reproduction amplifier 10. The signal from the output of the register 14 is fed to the first inputs of the subtractor 15, the second inputs of which from the second input bus 18 receives the code of the reference number. The code for the difference in the number proportional to the repetition pulse repetition period j and the reference number is fed to a digital-to-analog converter 16, the output of which produces the corresponding voltage applied to the reference input 20 of the analog-to-digital converter 1.1. The increase in the fidelity of digital information playback with increasing information density on a magnetic medium is determined by the fact that the reference voltage of the analog-digital converter 11 compensates for the change in the amplitude of the multilevel pulse caused by the change in the speed of movement of the magnetic carrier. The use of the proposed device allows to significantly increase the fidelity of reproducing digital information by increasing the information recording density, as well as reduce the requirements for the motor and nodes of the tape mechanism, thus reducing its cost. The invention of the device for recording and reproducing digital information and mt tint media, contains the first input bus connected via a connected input register, the first digital-to-analog converter, amplitude modulator and recording amplifier to the magnetic recording head, a control unit, the first output of which is connected via a write pulse generator to the second input of the amplitude modulator, the second output to the control input of the input register, and the third output to the control input amplitude recording 1agnitnuyu reproducing head connected posledova1telno included through the playback amplifier and analog-to-digital converts the output Tel tires of l and h ide o f its in that, in order to increase fidelity reproducing digital information by increasing the information recording density in 17 it has a counter, a register, a subtractor, a second digital converter and a counting generator of pulses, the output of which is connected to the input of the control unit and the first input of the counter, and the control output of the analog-digital converter is connected to the controlled input of the register and via serial connection foam meter, register, subtractor and the second digital-to-analog converter - with the reference input of the analog-digital converter, the second inputs of the subtractor are connected to the second input buses. Sources of information taken into account in the examination 1.Ryzhkov V.A. and others. External memory on magnetic media. M., Energie, 1978, p. 96 2. US patent number 3840891, cl. G P 5/00, 1974 (prototype).