Patent · US Expired

Multi-loop testing apparatus with field memory

US5260784A · kind A · utility

5Cited by
2References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 9, 1992
Grant dateNov 9, 1993
Priority date
Expiry dateApr 9, 2012

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N17/06
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Apparatus for adjusting a digital signal which is subjected to analog processing after being reproduced from a record medium. A prerecorded digital test signal is reproduced and written to a field memory which, during a normal playback mode, is used to store the digital video signal that may be reproduced. A loop, which is opened during the normal playback mode, includes DAC and ADC for circulating the digital test signal therethrough a number of times and is coupled to the field memory to receive the stored test signal. A detector detects changes in the test signal after having been circulated through the loop, and these changes are used to establish adjustment settings for adjusting the digital video signal during a playback mode.

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