Building a “Foxhole” Radio Receiver

Ever wanted to build one of the early radios by hand?

Did you know you can do it without special parts, just a coil of wire, a pencil, a piece of metal and a paper towel tube? Join this hands-on experience where you will learn to build the ingenious radio receiver built by Lieutenant M. L. Rupert in the 1940s. The radio doesn’t use a local oscillator so as to avoid being detected and was popular in areas (foxholes) where you didn’t want to be detected. You will be able to build your own radio on site and take home or simply come by to learn how it operates and take a turn at tuning a radio with a pencil point – the parts are simple, but perhaps not the tuning!  This hands-on experience is created by Prof. David S. Ricketts and is part of his work on disseminating wireless education in a more exciting way. See for educational materials one wireless systems and circuits.

AM Radio Receiver

Wikipedia: RBDiode.pdf