Video signal control pulse programme generator for video analyser - has free-running type quartz oscillator as beat generator and gate unit controlled by pulses from memory

摘要

The circuit arrangement has a counter (1) which is controlled by a beat generator (2) in the shape of a quartz oscillator and which is started by the synchronising pulse of the video signal through a gate unit (4). With the aid of these units the control pulse programme is read from the memory (3). The gate unit is controlled by the pulses from the memory in such a way that the gate is open only in a given time interval within the synchronising pulse, as provided by the norm. The quartz oscillator is of the free-running type. USE/ADVANTAGE - Test equipment. Exact synchronisation is achieved and guaranteed even when synchropulse is absent or when there is interference.