This small regulated power supply was found in a 1963 General Electric documentation. The special zener diode transistor can be replaced with an equivalent discrete configuration.
Based on Allegro's A6275, this circuit controls the brightness of various displays. The circuit is valid...
This small transmitter can act as a wireless microphone operating in the medium wave range,...
This is the circuit of an RCA Dimmer sold in 1967. With it it is possible to control a load up to...