Patent · US Expired

Head tracking control system for a helical scan VTR

US4420778A · kind A · utility

27Cited by
7References
15Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 23, 1981
Grant dateDec 13, 1983
Priority date
Expiry dateJul 23, 2001

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B5/588
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A video tape recording/reproducing apparatus for reproducing video signals recorded in successive parallel tracks on a magnetic tape, includes a magnetic head movable in a direction generally along each of the tracks in a scanning path from a beginning end to a concluding end thereof for reproducing signals recorded therein, and a bi-morph leaf for mounting the head and being operative to deflect the head in a direction transverse to the direction along the tracks. During the scanning operation, the bi-morph leaf is supplied with a dithering signal for wobbling the head transversely with respect to the longitudinal direction of the record tracks, a tracking error signal to correct deviations of the head trace from the tracks to be scanned and a slant compensation signal to correct any inclination tracking error of the head. During the non-scanning operation, a jump signal is supplied to the bi-morph leaf for deflecting the head to accurately scan the beginning of the tracks. The present invention also includes a sample and hold circuit and a comparator circuit for producing a polarity signal corresponding to the direction of any deviation between the scanning trace of the head and …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.