Synchronisation signal delay circuit for video recorder - separates horizontal and vertical pulses and forms twice horizontal frequency signal for generating delayed signal

摘要

The delay circuit obtains pulses of twice the line frequency, pulses with the line frequency and pulses with the vertical frequency from the original composite sync. signal. The composite sync. signal is then reconstructed from these three sets of pulses to give the original sync. signal shifted in time by the wanted amount. The original composite sync. signal is identified by pulse counting and the dividers needed for regeneration are preprogrammed by the result of the count such that the delayed sync. signal is in accordance with the original in terms of the number of different width pulses.