| 摘要 |
PURPOSE:To eliminate the variation in the rotation of a disc due to lack of bit or displacement of a track by providing a forcibly resetting circuit for specifying the maximum value of the reset period of a lamp wave generator. CONSTITUTION:A reproduction signal from a preamplifier 28 is inputted to a zero cross detector 30, the output of which is inputted to a double edge detector 32. The output of the detector 32 is inputted to a pulse generator 40 and a gate circuit 42 as a forcibly resetting circuit. The lamp wave of a lamp wave generator 34 is controlled by the output of a gate circuit 42, the output of which is applied through a peak hold circuit 36, a differential amplifier 20 and an amplifier 26 to a motor 12. |
