| 摘要 |
PURPOSE:To prevent malfunction of a signal processing circuit, by stopping the synchronous separating operation with a missing signal to outputting an asynchronous signal. CONSTITUTION:A signal recorded on a magnetic tape is extracted from a head. A video luminance signal FM-modulated is inputted to a terminal 1 of the signal processing circuit. If missing of signal takes place, the missing of signal is compensated by replacing a signal preceding one horizontal scanning period. The operation of the titled synchronous separator circuit 21 is stopped with a detecting signal from a missing signal detecting circuit 3. In this case, the synchronous separator circuit 21 outputs the asynchronous signal. Even if the missing of signal takes place for a long time and the missing is not compensated, the malfunction of a synchronous clamp circuit 11 is avoided. Since no synchronizing signal is generated during the missing of signal, a chrominance signal is interrupted automatically. Thus, the connection to the chrominance signal processing circuit during the missing of signal is omitted. |
