Apparatus for accurate adjustment of kinescope black level bias

摘要

Apparatus for adjusting the black image current bias of a kinescope in a video signal display system includes means for developing a control signal representative of the black current bias condition of the kinescope. The control signal is developed in response to a sample of an integrated group of sensed bias representative signals developed over several horizontal line intervals which are significant in number relative to the number of horizontal line intervals associated with a vertical field interval. In the case of a color kinescope having plural electron guns, plural groups of signals respectively representative of the black current bias of each electron gun are developed. The plural signal groups exhibit a mutually time sequential relationship and are processed by a common signal processor to develop an integrated version of each of the bias representative signal groups.