| 摘要 |
PURPOSE:To attain stable control desirably, by bringing a control signal within a control range, even if a reproduction synchronizing signal is missing. CONSTITUTION:A reproduction synchronizing signal missing detecting section 9 is a circuit detecting that a reproducing synchronizing signal is missing for a prescribed time or over, and it consists of a counter which is reset with the resproduction synchronizing signal and counts a reference clock. When the count value reaches a prescribed value or over, it is regarded as the missing of the reproduction synchronizing signal, a detected output is generated and a control signal (e) is muted by a muting section 10. Thus, if the reproduction synchronizing signal is missing for a prescribed time, the compensating control of the time axis fluctuating component is released, the control signal is muted, and the control signal is replaced into a prescribed value in the range where a controlled system does not cause any malfunction, for a kind of controlled system especially, into about a center value in the control range. |
