Patent · US Expired

Automatic head position tracking system for video signals recorded in a segmented format

US4933784A · kind A · utility

16Cited by
15References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 31, 1988
Grant dateJun 12, 1990
Priority date
Expiry dateOct 31, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B21/086
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Plural magnetic transducing heads are employed to record and reproduce video information that is stored in a segmented format. One head is in contact with the magnetic recording tape while the other head is out of contact with it. The position of the head which is in contact with the tape is controlled by a suitable ramp voltage generated in accordance with the ratio of actual tape speed to normal play speed, to maintain the head generally aligned with a track on the tape. The other head, which is out of contact with the tape, is also positioned in the same fashion. When a repositioning of the heads is required, a determination is made whether the track of information being reproduced by the head in contact with the tape relates to a particular segment of a field, for example the last field. If so, the head which is out of contact with the tape is appropriately repositioned so that it is in the proper location when it comes into contact with the tape to begin scanning the first segment associated with the next field that is being reproduced. Once the other head has come out of contact with the tape at the end of the previous field, it is repositioned to bring it to the location of …

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