This circuit is part of an article published in the March 1990 issue of Radio Electronics magazine. The sensor consists of a grid-shaped electrode shown in the figure.
We found this circuit that warns when the gate of a house is opened in an old documentation,...
With 3 transistors, we found this receiver in a documentation from 1966. The circuit has an output...
Generating a square signal (50% active cycle), this circuit was found in Siliconix documentation from...