This circuit for frequencies of 20 to 2 kHz was obtained in English documentation from 1966. The transistor can be any general purpose and powered by batteries.
This circuit was found in the March 1990 issue of Radio Electronics magazine. The circuit can be...
This circuit was found in a 1987 magazine. It generates signals in a range from 100 kHz to 10 MHz,...
Found in 1980s documentation, this circuit indicates the phase of a three-phase signal from the...