Found in an EDN from the 90s, this circuit has a distortion of only 0.003%. Capacitors and double potentiometer determine the frequency.
This transmitter is modulates a infrared light source from an audio signal. Applications include a...
This turntable filter was found on an 80's Elektor. The circuit makes use of operational features...
This circuit is from a Radio Electronics magazine from May 1989. The power supply must be...