This circuit allows the detection of RF signals using the lowest range of direct currents of a common multimeter. Equivalent diodes such as 1N34 can be used. The circuit is assembled in a ballpoint tube.
We found this sensitive moisture detector in an old documentation. The circuit uses a common JFET,...
This simple 2-transistor radio is from Radio Electronics in October 1952. The circuit outputs a...
This circuit was obtained in an American documentation of 1964. The transistors are of the time....