Patent · US Expired

Television signal detection apparatus

US5294977A · kind A · utility

24Cited by
1References
6Claims
0Family size

Inventors

Key dates

Filing dateNov 4, 1991
Grant dateMar 15, 1994
Priority date
Expiry dateNov 4, 2011

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N7/17309
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An apparatus and method for detecting and logging video outputs from a central control unit to one or more television receivers in which a remote unit in or in proximity to the or each television receiver detects by means of a tuned circuit the horizontal synchronization signal frequency of the receiver; the detected signal is modulated and fed to the central control unit where it is demodulated to produce a signal corresponding to the phase of the receiver horizontal synchronization signal characteristic of that receiver, the phase of the time synchronization signal of each of a plurality of video players is compared with the phase of the fed receiver signal to obtain a match; and a microprocessor logs the matched signals.

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