Found in an 80's Elektor, this circuit can use any equivalent optical coupler. The buzzer is of the Sonalert type with included oscillator.
This 1960s Signalite circuit uses two SCRs to achieve full wave control. The trigger elements are...
This voltage controlled oscillator uses a varicap to change the frequency. Usin a 100 turns coil...
July 2017 - Mouser Electronics announced the availability of its new ISO771x digital isolators...