| 摘要 |
PURPOSE:To obtain a digital audio disc player which performs always sure tracking, by driving a pickup motor intermittently plural times by a rough adjusting system for tracking thereby feeding the pickup to a specified extent. CONSTITUTION:An FF 7 is reset by the output of the 1st comparator 6a when the tracking servocontrol voltage which adjusts finely the optical system of an optical pickup for an optical disc rises above the 1st reference voltage and comes within the fine adjustment range. On the other hand, the FF 7 is set by the output of the 2nd comparator 5b when said voltage drops below the reference voltage for turning on and comes within the rough adjustment range. An oscillation circuit 8 of a rough adjusting system responds to the set output of the FF 7 and a pickup driving motor 5 is controlled by plural times of driving pulses. Thus, the motor 5 turns slowly and continuously and the pickup is fed to a specified extent by the torque having less variations, whereby the tracking is adjusted roughly and the digital audio disc player which performs always sure tracking is obtained. |
