Eighty years ago this month, the September 1943 issue of Radio Craft carried this circuit, dubbed the “barb-wire telephone.” It was sent in to the magazine by one Fred H. Randolph (from another submission to the magazine, apparently of Booneville, AR), who reported using it to communicate with a friend three miles away, courtesy of an iron fence wire. The circuit is nothing more than an audio amplifier using a carbon button mike, and puts out enough power to drive a speaker at the other end of the circuit, where an identical unit is located.