Cine projector with auto-timer - using comparator drive circuits, and preset and actual counters

摘要

The cine camera is provided with a programmed counter for sequence length and a comparator which counts the sequence length and stops the projection at the selected count. The operator merely presses the start button each time the next sequence is required. The counting circuits and drive circuits are completely electronic for a simple layout. Transistorised holding circuits ensure that a mere touch of the start control initiates the sequence. The counters are reset to zero each time the projector stops.