| 摘要 |
PURPOSE:To detect accurately an errorneous use of a disk containing signal recorded on its one surface only, and to prevent a malfunction, by providing an optical pickup which reads the recording signal of a disk, a speed control circuit of a motor and a fault detecting circuit. CONSTITUTION:The reproduced signal extracted by an optical pickup 10 is received by a haed amplifier 13 and amplified to be fed to a speed control circuit 11. The circuit 11 receives the reproduced signal of a disk 1 and controls the revolution of a motor 2 and at the same time gives a control to the pickup 10 to stabilize its tracking action. A fault detecting circuit 12 decides whether the control of the circuit 11 is steady or not for a prescribed period after the motor 2 is driven. When the control of the circuit 11 is not stabilized, the operation of the motor 2 is stopped. At the same time, the circuit 12 is connected to a fault display circuit 14 consisting of an LED. Then the circuit 14 glows when a fault is detected for the loading state of the disk 1. |
