This is a typical circuit of a PROM programmer from the 70s. It appeared in the magazine Radio Electronics in 1979. Note that the programming was done manually byte by byte using switches.
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...