This circuit with SCR is from a Radio Electronics magazine from September 1965. It is a commercial control from Heathkit for controlling universal motors.
This simple circuit makes it possible to test diodes and transistors for generating use and medium...
This 2.5 A power supply was found in a 90's QST magazine. The power transistor must be mounted on a...
This circuit is a digitally controlled variable capacitor. We found it in American documentation from...