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.
The basis of this circuit is the 723, an old integrated circuit not easier to find these days. The...
This circuit can be used to measure the frequency of a low frequency square signal. The signal can be...
September 2017 - Can be purchased from Mouser Electronics Triacs with 20 A and 30 A currents...