| 摘要 |
PURPOSE:To eliminate the abnormal operation of feeding of a pickup arm just after the servo operation, by detecting and amplifying the relative deviation between a video signal detection section and the pickup arm, providing a negative feedback to a detection signal with the output, when no arm servo is required and resetting the operation when the servo is required. CONSTITUTION:An FET10 turns on when no arm servo is required. When any output is given from a detection section, this output is inputted to an amplifier 11 and an amplifier 5, the output is fed back to an inverting input terminal of the amplifier 11 and the output signal of the amplifier 5 is decreased. When the arm servo turns on, an output signal of an arm servo on/off signal generating means 7 goes to L level and the FET10 is set. The output of the amplifier 5 is not fed back and the amplifier 5 obtains a required gain. Since the movement of the pickup arm just after the arm servo operation is small, no failure is produced and the mistake of tracking is eliminated. |
