This simple receiver of two transistors for the 80-meter range was found in an American documentation from the 1980s. The transistors admit equivalents and the antenna must be long.
This circuit was taken from the 1974 Ferranti transistor manual. Note the shapes of the signals....
This mini siren, found in a 2003 publication, powers a small piezoelectric transducer, but a...
This fuzz effect is from a 1988 Italian publication, but it can be easily assembled, as the...