We found this circuit in documentation from the 1980s. The transformer is of the low voltage type with a 1: 3 turn ratio and the transistors can be of general-purpose types.
This light-activated switch triggers a 6 V relay. The circuit can operate with 12 V and relays for...
The source of the figure was found in a 1981 magazine and is recommended for the experimenter's bench. The...
This is the circuit of a digital clock published in the January 1975 issue of Radio Electronics magazine....