This circuit was found in the February 1997 issue of Electronics Now magazine. The frequencies depend on the crystal and other tuned circuits.
This circuit was found in documentation from 1977. Its purpose is to diode-switch the frequency of a VFO....
This circuit is from a 1974 Ferranti transistor manual. The circuit is analog, and the components used...
Found in a 90s Popular Electronics, this circuit generates high voltage for radiation detecting...