Varactor diodes are our varicaps of today. This circuit for switching signals in an RF circuit was found in a Radio Electronics magazine from July 1982.
This original 70s RCA circuit appears elsewhere on this site, including original RCA...
This circuit, which makes an astable multivibrator, was found in the March 1973 issue of Radio...
This circuit uses two unijunction transistors and only one capacitor, generating signals at a...