Reproduction/output circuit for deep layer recording signal

Abstract

Abstract PURPOSE:To prevent an AM component produced by a surface layer recording signal from emerging into the demodulation output as a noise, by controlling the gains of an input signal to be applied to a demodulation means based on the amplitude change of a reproduced deep layer recording signal. CONSTITUTION:The reproduced deep layer signals received from rotary heads 11 and 12 and preamplifiers 13 and 14 are turned into speed signals by a changeover switch 15 and then supplied to an FM demodulator 18 via a gain control circuit 16 and a BPF 17. The output of the BPF 17 is fed back to the circuit 16 via a gain control signal detecting circuit 19 to delete the AM component of the noise caused by the AM modulation given to a deep layer recording signal from a surface layer recording signal. As a result, no AM component emerges to the demodulator 18 by a lower surface layer recording signal in the form of noise. Then the satisfactory deep layer recording and reproducing jobs are carried out.

Inventors

• 👤 Tetsuo Sakai
• 👤 坂井　哲郎

Bibliographic Details