| 摘要 |
PURPOSE:To prevent the deterioration in the picture quality caused due to the operation of a dropout compensation circuit by providing a signal level discrimination means applying switch control to a changeover means when a level of a video signal is a prescribed level or over based on a black level. CONSTITUTION:When a dropout is detected by a dropout detection circuit 16, a video signal level discrimination circuit 30 compares a reference level VR with a video signal level V1 just before the occurrence of dropout. In case of V1>VR, a control signal 104 is outputted to a switch SW1 to throw the contact from the position of a contact (b) to the position of a contact (a). An FM video signal from a magnetic head 12 is subject to interporation of dropout occurrence part by a dropout compensation circuit 18 via an amplifier 14 and the result is given to an FM demodulation circuit 20. The video signal processing circuit 22 fetches the demodulated output of the circuit 20 and applies conversion processing to a composite video signal of a prescribed format. In giving a conversion processing end signal 108 to the discrimination circuit 30, the circuit 30 throws the switch SW2 from the position of the contact (b) into the (a) and a video whose dropout is compensated is outputted from the processing circuit 22 to a monitor television 50.
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