Found in a 90s Popular Electronics, this circuit can power a miniature railroad with voltages of 15 V and currents up to 1 A. The circuit has soft start effects.
This circuit simulates an inductor. Or operational amplifier of old type, but a configuration is...
This circuit for the logic control of the 555 in a power supply was found in the October 1989...
This traditional configuration from a 1980 publication shows how a reed relay is used to control a 240...