Tracking control devices for video tape recorders
US4918546A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 21, 1985 |
| Grant date | Apr 17, 1990 |
| Priority date | — |
| Expiry date | Aug 21, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/592
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A tracking control device for a video tape recorder comprises a bimorph leaf on which a rotary playback head is mounted so as to be deflectable in a direction perpendicular to tracks to be scanned. A triangular wave signal generating circuit comprising cascaded flip-flops generates a substantially triangular wave signal which is supplied to the bimorph leaf to cause the playback head to wobble relative to the tracks. A detecting circuit detects an envelope signal in the signal reproduced by the playback head, and a phase comparing circuit which includes an exclusive-OR circuit compares the phase of this envelope signal with the phase of the triangular wave signal. The output of the phase comparing circuit is fed back to the bimorph leaf to effect tracking correction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.