This circuit provides a signal that is twice the frequency of the input signal. The circuit was found in the April 1990 issue of Radio Electronics magazine.
This full wave source uses germanium diodes, and its current is a few milliamps. We found it in an...
This circuit is from a 1968 documentation. It makes use of thermistors (NTC) to indicate...
This small transmitter has an RF amplifier stage with coupling made from the central socket of the...