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 purpose of this project is to monitor remote loads. The windings are made in a burnt...
The scale of this scale uses LEDs, and its accuracy depends on the number of LEDs. We found this...
We find this circuit in an American documentation from the 80's. The circuit has the coil given by the...