This simple circuit, found in American documentation, uses only one relay that locks when any of the sensors is activated. To reset, simply turn off the power for a moment.
This pulse width modulator is from the SGS Integrated Circuits Manual 1982, the operational can be...
We found this circuit in a publication from the 1970s. The circuit detects when the pulse duration is...
This circuit using current components was found in an old documentation. It is a sequential circuit...