SYNCHRONISATION DEVICE FOR A CHARACTER GENERATING CIRCUIT AND A VERTICAL DEFLECTION CIRCUIT, AND TELEVISION RECEIVER COMPRISING SUCH A DEVICE

摘要

Devices for displaying a label on a visualization screen. The information display inserted into a background image is provided by a character-generating circuit. The stability of the label requires synchronization of the vertical scanning of the image and of the label. This synchronization is obtained by measuring the current which flows through the deflector of the cathoscope tube: the information acquired, amplified, is applied to a threshold detector which controls the display circuit. The beginning and the end of synchronization are regulated by two reference voltages. The invention applies to the display of information on television receiver or visualization console screens.