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.
The components used in this 80's circuit are not common today. The circuit is very sensitive and must...
The circuit shown is for testing both signal diodes (low current) and rectifiers (high current). The...
Connected to the output of an audio amplifier or radio this circuit indicates the level of the...