Video signal DC variation compensation method for color television receiver subtracts DC voltage proportional to DC variation from video signal before addition with offset voltage

摘要

The DC variation compensation method uses subtraction of a DC voltage proportional to the ground potential of the synchronization pulses from the video signal, with cyclic sampling of the latter, for detecting the DC voltage variation. A DC voltage proportional to the DC voltage variation is fed to a subtracter or adder (3) for providing a video signal which is free of DC voltage variations, to which a defined offset voltage (7) is added. An independent claim for a video signal DC variation compensation circuit is also included.