This circuit was found in documentation for radio amateurs of the 1980s. This is the so-called roger-beep, which is the beep that is transmitted when the talk-listen function is changed.
This simple field strength meter was found in a 1967 documentation. The transistor is germanium, and the...
This is yet another version of the light-controlled oscillator that can be found on this website. This...
Found in a 1969 documentation, this circuit for the 20 MHz band does not use a transformer. The circuit is...