So basic they were built in fox holes
Iopened another old box. A Cub Scout book from 1952 was marked to a page on basic crystal radios.
Crystal radios do not need a power source. They operate on energy sent out by the radio transmitter. It is a “detector” made of an antenna, a coil of wire and earphone to vibrate with a radio signal. .
This is old technology so basic that during WWII soldiers built “Fox Hole Radios” out of scrounged bits of this and that.
Wire wound around a stick became a coil. Lacking crystal detectors they used a rusty razor blade touching a piece of pencil lead in the circuit. They found headphones in destroyed vehicles, attached a wire antenna and tuned in music and news.
A prisoner of war camp is one of the last places you would expect to find a radio receiver but in a camp of several hundred to several thousand guys there was a university of skills.
“Prison Camp Radios” were not abundant but they existed. Execution was certain if a prisoner was discovered with a receiver. The captors didn’t want prisoners to have news from the outside, in particular if it was encouraging.
Voice of America transmitters broadcast from liberated cities in Europe and Asia. The BBC broadcast news from British transmitters late at night. Listeners in camps took notes and distributed news by word of mouth throughout the camp.
Prisoners saved everything. Any found piece of wire, button, nail, screw was kept, collected, sorted, indexed and used to its full extent.
Razor blades were in short supply but there were pieces of “coke,” a form of coal, which they used as a “detector.” Everything had to be built from scratch including headphones.
The Germans and Japanese did not knowingly supply parts for contraband receivers but they supplied an elaborate antenna system. When electrical power was switched off at night receivers were hooked up to the camp wiring system or to the barbed wire surrounding the camp as an antenna.
Prisoners used items from Red Cross POW packages to bribe German guards. Cigarettes, chocolate bars and coffee were rare in Germany at the time.
Reliable news on the progress of the war was scarce. Prisoners usually knew far more of the war’s progress than their captors.
It was a criminal offense for people to listen to foreign broadcasts if their radio could receive them. The government allowed radios such as the inexpensive “Volksempfaenger. “This radio was useful as a Nazi propaganda tool but were not capable of receiving short wave signals.
After June 6, 1944 news of the war became more precious. Everyone wanted to know what was happening. Prisoners in the camps knew the Allied forces were prevailing.
Today there are competitions in building authentic recreations of prison camp radios.
This was truly making something useful out of nothing.