General-purpose timer from transistor logic to auxiliary equipment.
This paper describes a low-cost circuit for the control and timing of auxiliary experimental equipment by a variety of signals from 5 V, integrated-circuit logic. The circuit is designed for variable timing and switching up to 240 AC V at 3 A, with two independent timing parameters, delay and duration, in response to positive-going or to negative-going logic signal transitions.
Electronics, Medical↗