| 摘要 |
PURPOSE:To reproduce a PCM sound signal faithfully by producing a more feedback effect on frequency characteristics of a reproducing preamplifier circuit which includes a magnetic head and a rotary transformer when the PCM sound signal is reproduced than when a video signal is reproduced. CONSTITUTION:A signal reproduced by a magnetic head 12 for reproduction is supplied to the reproducing preamplifier circuit 13 through the rotary transformer 11. The circuit 13 consists of a high gain amplifier 14, DC feedback path 15, and feedback dumping circuits 16A and 16B, which are switched with time by controlling a switch circuit 17 with the output timing signal of a timing control circuit 18. Namely, when the video signal is reproduced, frequency characteristics of the circuit 13 including the head 12 and transformer 11 are so set that resonance is obtained almost at a white peak carrier frequency, and a feedback effect is produced when the PCM sound signal is reproduced to widen frequency characteristics. Thus, the PCM sound signal is reproduced with fidelity. |
