These 6 to 12 V source with current up to 100 mA was found in Radio Electronics magazine from June 19666. The source has a current indicator and uses transistors of the time.
This circuit works with small 5 V incandescent lamps but can be modified to operate with LEDs. The...
This circuit found in Radio Electronics can be used in games to produce a random pulse train. The...
This photometer is based on a Wheatstone bridge that must be balanced by the linear potentiometer P1. The...