Composite Video Sync Separator Performance Enhancement
Original Publication Date: 1988-Jul-01
Included in the Prior Art Database: 2005-Feb-15
This article describes a method for improving the operation of a video sync separator circuit for use in a graphics-over-video display system, using a Video Disc Player (VDP) as the video source. In such a system, problems may be caused by video signal characteristics of various types of VDPs. One of the problems is a video "jitter" at the top of the screen when the VDP is in still-frame mode. Another problem is a video curvature at the top of the screen. These two problems are usually the result of the sync separator's horizontal phase-locked loop (PLL) having a slow response time to variations in the composite video signal. The solution to these problems is to reduce the response time.