| 摘要 |
PURPOSE:To reproduce a video signal and an audio signal with optimum frequency characteristics by using a negative feedback circuit to change the frequency characteristics of a regenerative amplifier to two kinds and distinguishing between the 180 deg. part, and the >=180 deg. part, and switching and outputting them from the regenerative amplifier. CONSTITUTION:A magnetic tape 3 has the 180 deg. part, where the video signal is FM-recorded, and the >=180 deg. part where the audio signal is PCM-recorded, and signals detected by magnetic heads 2a and 2b are inputted to head amplifiers 7a and 7b and are amplified. These amplifiers 7a and 7b have frequency characteristics changed to two kinds by negative feedback circuits 8a and 8b. That is, feedback ratios of circuits 8a and 8b are changed by a head switching pulse S1 inputted through an inverter 10, and the frequency characteristic of one of amplifiers 7a and 7b is changed to the characteristic most suitable for the video signal, and that of the other is changed to the characteristic most suitable for the audio signal. A switching circuit 9 receives the pulse S1 and switches heads 2a and 2b to reproduce outputs of amplifiers 7a and 7b, and the video signal and the audio signal are separated from each other and are outputted.
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