| 摘要 |
PURPOSE:To prevent any hindrance on a video reproducing operation due to mis-discrimination by discriminating a PCM recording tape based on a discriminated pilot signal and making the discrimination ineffective at the video reproduction. CONSTITUTION:Since a pilot detection circuit 18 might detect a low frequency conversion chrominance signal in error in reproducing a video recording tape, a circuit detecting the presence of a reproduced video signal is provided at the video reproduction so as to not cause the muting. That is, an output of a de-emphasis circuit 8 of a luminance reproduction system is given to a SYNC presence discrimination circuit 21 to discriminate the presence of a synchronizing signal SYNC. A synchronizing signal is detected at the video reproduction and an output of the discrimination circuit 21 goes to a high level. The output is inverted to a low level by an inverter 22, an AND gate 19 is closed by the inverted output, resulting that an output of the pilot detection circuit 18 having a possibility is mis-detection at the video reproduction is cut off by the AND gate 19 to turn off the muting function.
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