| 摘要 |
PURPOSE:To prevent a servo system from being easily switched by a small hurt and to stabilize operation, by switching a muting signal to use it as a gate signal. CONSTITUTION:A signal picked up by a pickup PU3 is decoded as a voice data by a digital processing circuit 30. If a reproduced signal is erased by a hurt on a disc 2, connection to the circuit 30 is switched to a reproducing speed detecting circuit 5 by a switching controlling circuit 7. When the hurt is small and a voice is not muted, the output of an error detecting circuit 33 is kept to the ''Low'' level, the output of an AND gate 31 is not changed and a switching circuit 6 is also kept at the side of a synchronous signal detecting circuit 4. After passing through the hurt part, the synchronous signal detecting circuit 4 detects a synchronous signal again and the output of the switching controlling circuit is turned to the ''Low'' level. |
