AUTOMATIC SYNCHRONIZATION SWITCH FOR MULTIPLE PICTURE DISPLAY.

摘要

A video display system comprises a video display for simultaneously displaying pictures representative of first and second video signals. A synchronizing circuit (700) selectably synchronizes the video display with either one of the first and second video signals. A horizontal synchronizing component is separated from the first video signal and detected by a sensing circuit (710). A circuit (708) for controlling the selectable synchronizing circuit is responsive to the sensing circuit. The video display is synchronized with the first video signal when the horizontal synchronizing component separated from the first video signal is sensed and is otherwise synchronized with the second video signal.