| 摘要 |
FIELD: magnetic recording of electric signals. SUBSTANCE: channel has circuit for recording and playback, which is located in unit of magnetic heads, information carrier and amplifiers. In addition device has modulator with pulse- width modulation of analog signal which is encoded as sequence of half-period pulses with varying duration and alternating polarity. Said modulator is inserted between channel input and circuit input. In addition device has generator of rectangular pulses which output serves as channel output, and phase shifter in quarter phase. Said phase shifter is inserted between circuit output and input of generator. Another claim of invention describes device design in which modulator provides pulse-width modulation of analog signal which contains alternating pieces of sine curve of varying duration and which limit values are pi/2 and -p/2. Said modulator is inserted between input of channel and input of circuit. In such device design input of generator is connected to output of circuit. Another claim of invention describes device which has additional amplifier with automatic control of gain and bandwidth. This amplifier is inserted between output of circuit and input of generator. EFFECT: increased functional capabilities. |
