This is the old name given to flip-flops or biestable multivibrators. In fact, this is a 1967 Ferranti circuit, triggered by a light sensor.
This series sensor circuit is from 1995 Popular Electronics. The circuit can use any SCR and the...
The circuit is a multivibrator version using two NPN general purpose transistor. This circuit can...
This circuit is from 1976 documentation. It uses the operational amplifier 709 which is no longer...