Circuitry for an audio or video disk player
US4803676A · kind A · utility
1Cited by
6References
11Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Dec 22, 1986 |
| Grant date | Feb 7, 1989 |
| Priority date | — |
| Expiry date | Dec 22, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B21/106
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An arrangement for obtaining precise scanning of audio and/or video disks with contactless scanning. A combination of coarse and fine drives serve to effect radial servo-readjustment. A radial error signal is applied to a comparator, so that when the radial error signal exceeds the threshold value set by the comparator, the coarse drive is driven with full operational voltage. The precision or fine drive has a control parameter which provides the radial error signal for operating the coarse drive. The comparator has a variable threshold for detecting the direction in which the coarse drive is to be driven.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.