This circuit is from a 1924 book by Gernsback. The receiver uses two tubes and listens to headphones. Power is supplied by battery with the indicated voltages.
This is the circuit of a commercial radio sold in Japan in the 1960s. The IF is 455 kHz, and the...
In this radio the coil can be made with 70 + 30 turns of wire 28 to 32 in a cardboard or PVC tube...
This circuit consists of a sequential that is activated when you step on the brake pedal (brake...