How to Make a Crystal Diode Radio

Preparation

• 1

  Poke two holes with a nail 1/2 inch apart and 4 inches below the top of the oatmeal container. Weave the magnet wire through the holes, leaving 2 feet of excess wire on the free end.

• 2

  Wrap the wire five times around the container keeping each turn close together. At the sixth turn, twist the wire into a 1/4-inch loop sticking out from the side of the container. Repeat this process until you have wrapped the wire 40 times around the container and twisted eight equally spaced loops.

• 3

  Poke two holes below the final loop, thread the wire through the holes and cut the wire, leaving 2 feet of excess.

• 4

  Remove the plastic coating of each wire loop using sandpaper, and strip 1 inch of insulation off the upper and lower magnet wire ends.

• 5

  Drill a 1/4-inch hole in both corners of one 12-inch side of the plywood board. With the board oriented so the holes are at the bottom left and right, drill two additional holes in the upper right corner 1/2-inch apart, one above the other. Maintain this orientation throughout the assembly.

• 6

  Insert a machine screw through each hole, threads sticking up. Tighten each screw with a nut.

• 7

  Glue the oatmeal container bottom to the middle of the board.

Assembly

• 8

  Twist the upper magnet wire end around the screw in the bottom left corner of the board. Twist the lower magnet wire end around the bottom right screw.

• 9

  Cut a 4-inch length of magnet wire and attach the lower right screw and the bottom upper right screw.

• 10

  Connect the crystal earpiece wires to the upper right corner screws, one to the top screw and the other to the bottom. Attach the resistor across these upper right corner screws as well.

• 11

  Twist the striped end of the diode around the top upper right corner screw. Connect the other diode end to the middle loop on the oatmeal container using alligator clips.

• 12

  Tighten a second nut over each screw to secure the connections.