| 摘要 |
PURPOSE:To obtain a driving control unit which has an excellent response characteristic and has no disorder in a servo-system in the retrieval at a high speed, by controlling rotation of a disk in accordance with a reproduced signal from a video disk, at the time of normal reproduction, and in accordance with the rotation speed of the video disk at the time of high speed retrieval. CONSTITUTION:At the time of a normal reproduction, a high level signal is provided from a terminal 6, and a switch 15 selectively outputs a reproduction control signal and a phase comparison value, and a driving motor 8 of a disk 1 is servo- controlled. On the other hand, when an input from a terminal 16 is varied to a low level to have a high speed retrieval mode, the switch 15 selects a phase comparison signal by a phase comparator 4', comparing a rotary speed detection signal of the disk, which has been outputted from a pulse generator 9, with a reference signal which has passed through a frequency divider 14. |
