| 摘要 |
PURPOSE:To improve hearing sense by controlling a switch circuit and a holding circuit by using two delay circuits in a reproducing device which switches the outputs of two rotary heads by a switch circuit and outputs them from a sample holding circuit. CONSTITUTION:An FM audio signal 17A from a rotary head 1 is applied to the switch circuit 6 through a preamplifier 4 and an FM audio signal from a rotary head 2 is also applied to the switch circuit 6 through a preamplifier 5. Then, the switched signal is sent to the sample holding circuit 9 through a BPF 7 and a demodulator 8 and a playback output is sent out of the sample holding circuit 9. In this constitution a head switch signal (c) from a control head 3 is applied to the changeover switch 6 and also applied to the holding circuit 9 through a monostable multivibrator 12 to reduce noise pulses. In this case, the noises are removed completely by providing a delay circuit 11 additionally and newly in front of the vibrator 12 and shortening hold pulse time width, thereby improving hearing sense.
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