This 4-voltage power supply using zener diodes has a maximum recommended current of 25 mA. The circuit was found in the May 1966 Radio Electronics magazine.
This simple MW radio does not need an external antenna to pick up local stations. It was found in a...
This simple receiver picks up local MW stations with playback on a small speaker. The antenna must...
This is a converter stage found in old transistor superheterodyne radios. The circuit is for...