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 generates pulses at a frequency that can be adjusted by a potentiometer. The circuit is...
This oscillator uses a small IF transformer taken from an old transistor radio. FET admits...
Found in a 1970 EEE, this circuit generates signals that depend on the C1 capacitor. Transistors are...