| 摘要 |
PROBLEM TO BE SOLVED: To provide a synchronizing separator circuit which is robust against transmission system distortion, ghost, offset beat, etc., even in a weak electric field. SOLUTION: The synchronizing separator circuit is provided with a sample- and-hold circuit 3 to obtain the pedestal level of a video signal, a peak holding circuit 4 to obtain the peak level of a synchronizing signal included in the video signal, a voltage division circuit B which divides the voltage between output voltages of circuits 3 and 4 to output an arbitrary voltage between them, and a comparator 5 to compare the output voltage of the voltage division circuit B with the video signal and detects the synchronizing signal by the output of the comparator 5. In the synchronizing separator circuit, a voltage- current conversion circuit A is provided which varies the output voltage of the voltage division circuit B by a desired value in accordance with the voltage difference between the output voltage of the sample-and-hold circuit 3 and that of the peak holding circuit 4.
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