Patent · US Expired

Circuit for analog digital conversion of a color television signal employing variable signal amplification

US4628345A · kind A · utility

1Cited by

8References

19Claims

0Family size

Assignee

Deutsche Thomson-Brandt GmbH · DE

Inventors

Erich Geiger · St. Georgen im Schwarzwald, DE
Bernhard Otto · Schifferstadt, DE
Jurgen Kaaden · Villingen-Schwenningen, DE

Key dates

Filing date	Sep 14, 1984
Grant date	Dec 9, 1986
Priority date	—
Expiry date	Sep 14, 2004

Classification

Technology area (CPC H)Electricity
CPC primaryH04N11/08
WIPO fieldAudio-visual technology
WIPO sectorElectrical engineering

Abstract

An analog digital conversion is provided for two color difference signals, for example for a recording according to a timeplex method. The color difference signals are adjusted in their amplitude at the input of the analog digital converter such that the modulation range of the analog digital converter is always fully used independent of the original amplitude of the color difference signal. The amplitude is restored back to its original value after a digital to analog reconversion. This results in an improvement of the signal to noise ratio during the transmission. The amplification provided to the various signals can be controlled by comparator circuits comparing the signal level with a reference signal.

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