During WWII, hundreds of soldiers were stuck in trenches and foxholes. To pass the time and to get information, the soldiers came up with brilliantly simple methods of constructing radios that worked without batteries. These radios, called foxhole radios because of where they were used, were made out of little more than a few pieces of wire and bits of metal. They can still be made today---the instructions below show you make one in minutes.
Instructions
Main Parts
1. Wrap the magnet wire around the length of the cardboard tube about 100 to 150 times. Leave enough room on at least one end to secure the tube to the Styrofoam.
2. Attach one end of the magnet wire that comes off the tube to the antenna wire by wrapping the ends of the wires together.
3. Attach the other end of the magnet wire that comes of the tube to the ground wire by wrapping the ends of the wires together. This wire will run from your radio to metal that eventually contacts the earth (hence, the term ground wire). Attaching the ground wire reduces static electricity in the radio circuit that can cause interference.
4. Glue or tack the cardboard tube in place on the Styrofoam.
Additional Wires and Parts
5. Cut the connector end off the earpiece and trim back insulation from the wire a bit. Wrap the exposed earpiece wire to the joint of the magnet and ground wires.
6. Attach the alligator clip to the joint of the earpiece, magnet and ground wires.
7. Wrap the tip of the short wire to the joint between the magnet wire and antenna wire. The short wire will connect the magnet and antenna wires to the transistor of the radio (the copper penny).
8. Heat the copper penny in a flame until it turns black with carbon. Connect the second end of the alligator clip to the penny and glue the penny in place on the Styrofoam.
9. Secure the ground wire to any metal that goes into the ground.
10. Put the earpiece in your ear and touch the short wire that runs off the magnet wire joint to the carbonized penny. You should be able to pick up at least a local radio station.
Tags: magnet wire, ground wire, short wire, wire joint, wire that