This circuit was found in the December 1992 issue of Radio Electronics magazine. The current is a few mA and the maximum input voltage is around 12 V.
The first transformer is a driver found on transistor radios and the second a small output...
This circuit, found in a 1979 documentation, consists of a small inverter that applies a voltage to...
Found in a Popular Electronics from the 90s, this shield is activated by a 20 mA current. The...