| 摘要 |
PURPOSE:To securely and automatically discriminate a recording mode by extracting the DC level in the pedestal level transmission period of a reproducing video signal, and comparing it with a reference value for decision making. CONSTITUTION:A VTR reproducing output is demodulated by an FM demodulator 3, has its carrier component removed by an LPF 4, and is supplied to a sample holding circuit 5 and also to a synchronizing signal separating circuit 6, from which a horizontal synchronizing signal is extracted. A delay horizontal synchronizing signal is supplied through a monostable multivibrator 7 and the DC level in the pedestal level transmission period of the reproducing video signal which varies in recording mode is detected from the circuit 5 and compared by a comparator 8 with the reference level, so that a comparison result for deciding the recording mode automatically and securely is outputted.
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