This circuit uses a 100 kHz crystal, but nearby frequencies can be obtained with appropriate crystals. Components are still common today.
This charger for a maximum current of 15 A was obtained from an American 80's schematics. The triac must...
This simple photometer uses a 1 mA milliammeter and a common phototransistor. The circuit has its...
Indicated for stereophonic sound applications, this circuit was found in the April 1983 issue of...