This circuit is from 1964 documentation but can be easily implemented based on current components. Input waveforms and detection are shown next to the diagram.
This circuit produces a 2 kHz tone on a standard piezoelectric transducer. The circuit can be used as...
This circuit can be used in 0,5 to 37 V Power supplies and output currents up to 3 A. The...
This circuit is from an ancient American documentation. The coil is frequency dependent and the...