Found in a 1968 Ferranti documentation, this circuit can be implemented with modern equivalent semiconductors. With the indicated components the load can be a lamp up to 1 A.
This circuit increases the sensitivity of a multimeter in the measure of small alternating...
This circuit triggers a buzzer or other warning device when the light falling on the sensor is cut...
This circuit open and close the relay in intervals adjusted by the potentiometers. The capacitors...