Found in a publication by Gernsback from 1960, this circuit uses germanium transistors of the time and commercial coils. It can be changed to operate with modern transistors and other wavebands.
This simple radio uses few components due the direct coupling of the transistors. Coil is formed...
The inverter circuit shown in the figure provides a voltage of around 110 V with a rectangular waveform...
This circuit operates at a frequency of 80 KHz and modulation up to 60 kHz. The circuit is from...