| 摘要 |
PURPOSE:To feed while tracking a reproduction element stably, by detecting a DC component in a tracking error signal periodically, and gradually increasing the width of feed pulse when the detected value beyond a specified value continues for many times. CONSTITUTION:A tracking error signal incoming to an input terminal 1 is applied to an inverting input terminal of an operational amplifier 17, and a low level signal is outputted when the DC component is a specified value or more, and outputs a high level signal when smaller. This output signal is given to a microcomputer 18, and when the detected value more than a specified value keeps for a plurality of number of times, a feed pulse width applied to a playback element carrying feed motor is gradually increased. Thus, the circuit constitution is made simple and feeding is made stably while tracking the playback element. |
