SU625236A1 - Apparatus for magnetic recording and reproducing of width-modulated signals - Google Patents

Description

The invention relates to the field of magnetic recording, namely, devices for magnetic recording and reproduction of a pulse-width modulated signal.

A device for magnetic

recording and playback of a pulse width modulated signal containing an input bus connected via a pulse-width modulator with two recording heads, and playback heads connected via a pulse-width demodulator and a low-pass filter with an output bus {ij. The known device provides - compensation of the distortions arising in the process of magnetic recording and reproduction of the width-modulated signal.

The disadvantage of such a device is the complexity of its design.

Also known is a device for magnetic recording and reproducing a modulated sigal containing a soft bus connected through an amplifier to a pulse-width modulator whose output is connected to the winding of the recording head and a reproducing head connected to the playback amplifier having its output connected to a pulse demodulator made with a control input and connected via a low-pass filter to the output one. This device has a relatively simple design.

Its disadvantage is a significant error in the result of reproduction of the width-modulated signal.

The purpose of the invention is to reduce the error of the result of reproduction of the width-modulated signal.

Claims (2)

This is due to the fact that a generator of a sinusoidal reference signal, the output of which is connected to the winding of the recording head, and a series-connected band-pass filter of the reference signal, an amplitude detector and an additional low-pass filter connected between The output amplifier of the reproduction and the control unit of the 1 MULIC modulator. In the drawing, a block diagram of a device for magnetic recording and reproduction of a pulse-width modulated signal is given. It contains an ochojay bus .1 connected through an amplifier 2 to the input of a pulse-width modulator 3, which includes a write amplifier. The output of the latitude of the module of the modulator 3 is connected to the winding of the recording head 4, coupled with the moving magnetic tape 5. The output of the sinusoidal reference signal 6 is also connected to the winding of the recording head 4, the proposed device also contains a reproducing head 7, mating with a moving magnetic tape 5 And connected to the input of the amplifier 8 playback. The output of the reproducing amplifier 8 is connected to a pulse-width demodulator 9, which is provided with a control input and is connected to the input of a low-pass filter 10; The output of the low-pass filter 10 is connected to the output bus 11. The proposed device also contains a 12-support signal connected in series, an amplitude detector 13 and an additional low-pass filter 14 included between the output of the playback amplifier 8 and the control input -pulse demodulator 9. In the proposed device, the pulse frequency of a pulse-modulated signal is much higher than the upper frequency of the modulating signal, and the frequency of the sinusoidal reference signal is key among them. At the same time, the speed of movement of the magnetic tape 5 is quite small, which ensures that only the low-frequency part of the pulse-width-controlled signal is recorded on it. The use of the invention makes it possible to significantly reduce the inconsistency of the result of reproduction of the width-modulated signal. In addition, the use of the invention provides the relative simplicity of the design of the device for magnetic recording and reproducing the lat-modulated signal and reducing the requirements for the magnetic tape. The invention is a device for magnetic recording and reproduction of a pulse-width modulated signal, containing an input bus connected via an amplifier to a pulse-width modulator, the output of which is connected to the winding of the recording head, and a reproducing head connected to the playback amplifier, the output of which is connected to the recording head. a pulse demodulator made with a control / input and connected via a low-pass filter to the output bus, characterized in that, in order to reduce the error of the result Playback, a sinusoidal reference signal generator, the output of which is connected to the winding of the recording head, and a series-connected bandpass filter of the reference signal, an amplitude detector and an additional low-pass filter connected between the output of the playback amplifier and the control input of the pulse width demodulator are entered into it. Sources of information taken into account in the examination: 1. US Patent No. 3012234, CL 344174. 1, 1961. 2.Patent of Great Britain M “1171316, cl. Q 5 R, 1969.