3 A switched regulator (CB8859E)

Found in a 90s Popular Electronics, this circuit provides a current of 3 to 5 A depending on the transistor.

Reed Relay Controlling a Triac (CB12184E)
This traditional configuration from a 1980 publication shows how a reed relay is used to control a 240...
Optocoupler TTL (CB12965E)
This coupler allows the triggering of a TTL port or flip-flop from an SCR. The resistor R must be...
RCA Receiver (CB23624E)
This RCA commercial radio had its circuit published in Radio Electronics magazine in August 1959....