This little project is a sure interest grabber with students of electronics of any age. Recommended for Boy Scout Merit Badge and Cub Scout Activity for requirements.
It does not require a great amount of skill, but a little application will produce a good basic radio receiver. Construction is fairly simple. This radio DOES NOT require batteries to operate; rather, it uses simple electrical principles to power itself. It does not include the Double Headset shown but does include a Crystal Earphone. Tuning is done by rubbing a piece of metal (large paper clip included in kit) across the coil of wire which is wrapped around a toilet paper tube.
The best antenna for this radio is simply a really long wire, mounted as high above the ground as you can make it. Though sometimes just connecting the antenna lead to a bed spring can bring surprising results, especially in city areas, or close in to a transmitter station in the country.
List of Parts provided in the CRYSTAL RADIO SET #8893
8 OF BRASS FURNITURE THUMB TACKS
70′ OF COPPER MAGNET WIRE #30
1 OF LARGE PAPER CLIP
1 PIECES OF SOLID 4″ HOOKUP WIRE
1 OF 470 PFD DISC CAPACITOR
1 OF 0.01 MFD DISC CAPACITOR
1 OF GERMANIUM DIODE
1 CRYSTAL EARPHONE WITH WIRES
1 Complete set of INSTRUCTIONS and DIAGRAMS
1 COMPONENT PLACEMENT DIAGRAM TO GLUE TO YOUR WOOD BASE
You need to supply a discarded cardboard tube from a toilet paper roll, an 8″ x 5″ block of Pine wood, or chipboard to use as base, and some radio cement (clear glue) to hold the coil of wire in place on the toilet paper tube.
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