This 1924 receiver uses a battery for the tube filaments and a high voltage battery for the amplifier and detector circuit. The speaker is kind of high impedance era.
Found in an American 1980s documentation, this circuit generates high-intensity pulses for a...
This powerful FM transmitter was found in a 2002 documentation. The output transistors must be...
This circuit was obtained from a 1966 documentation. The transistors are of the time. The circuit...