DUAL MODE HORIZONTAL DEFLECTION CIRCUIT

摘要

A horizontal deflection start-up circuit operates in the absence of trigger pulse normally derived by an AFPC loop. During normal operation, the AFPC loop generates the trigger pulses based on a synchronized phase relationship with sampled flyback pulses. During receiver start-up, the flyback pulses are not present and no trigger pulses are generated. The start-up circuit provides auxiliary pulses which occur later in time than the normal occurrence of the trigger pulses. Means are provided for applying the auxiliary pulses to the horizontal deflection circuit only in the absence of normal trigger pulses.