From the receiving side of the circuit, the antenna was made of random wire coupled with the inductor L1 having a single turn while inductor L2 has 4 turns wound around a 35 mm film container. Both ...

This is a compact three transistor, regenerative receiver with fixed feedback. It is similar in principle to the ZN414 radio IC which is now no longer available. The design is simple and sensitivity ...

Crystal radios used to be the “gateway drug” into hobby electronics. Trouble was, there’s only so much one can hope to accomplish with a wire-wrapped oatmeal carton, a safety-pin, and a razor blade.

Sixty-one years ago, on January 31, 1954, Edwin Armstrong, who invented the regenerative, super regenerative, and superheterodyne detector circuits for continuous-wave and amplitude modulation and the ...

Crystal radios used to be the “gateway drug” into hobby electronics. Trouble was, there’s only so much one can hope to accomplish with a wire-wrapped oatmeal carton, a safety-pin, and a razor blade.