Found in a documentation for radio amateurs from the 90s, this circuit is suitable for RF measurements in transmission systems. The potentiometer must be of a special type.
Found in American documentation from the 1980s, this circuit operates in the frequency range 0.5...
This circuit was found in an American 1980s documentation. The transistors admit equivalents and the...
This circuit consists of an electrostatic sensor that can check if a cable is energized by simply...