How to Build a Radio for Science Project
- 1). Poke two small holes near the top of the plastic bottle or oatmeal container with a nail or knife. The holes should be a 1/2-inch from the top and a 1/2-inch apart from each other.
- 2). Using the same method, poke two small holes near the bottom of the container.
- 3). Slide the wire through the two holes at the top of the container and pull 10 to 12 inches through to the other side. Secure the wire by taping it into place where it goes through the holes.
- 4). Wrap the long side of the wire around the top of the container five times, then wrap a small loop around the pen or pencil, alongside the container.
- 5). Wrap the wire around the container five more times, followed by another loop around the pen or pencil. Continue doing this until the entire container is wrapped in wire and you've reached the two holes at the bottom of the container.
- 6). Run the wire through the two holes at the bottom of the container and cut it so that the length running past the two holes at the bottom is the same as the length running through the two holes at the top.
- 7). Remove the insulation from the last inch of the ends of the wires by scraping it off with a utility knife. Slide the pen out, and remove the insulation from the loops that are sticking out on the side of the container.
- 8). Solder or tape the Germanium diode to the end of the wire at the bottom of the container.
- 9). On the cord attached to the phone receiver, locate the plastic jack that plugs into the wall. Cut it off. Leave the other end plugged into the receiver.
- 10
Check the wires inside the insulated phone cord. If there are yellow and black wires, these are the ones that you want to use. If they're all the same color, take the insulation off the wires using a wire stripper or utility knife. Touch one wire to the positive (+) end of a AA, C or D battery, and another wire to the negative (-) end. If you hear a clicking sound in the phone receiver, those are the wires that you want. - 11
Solder one of the wires from the phone receiver to the wire of the Germanium diode that's not hooked up to the wire from the container. - 12
Solder the other wire from the phone receiver to the wire at the top of the container. - 13
Take the stranded insulated wire outside and throw it up in a tree, over a roof, or onto a similar tall structure. The higher the antenna, the better the reception. Do not under ANY circumstances use a live power line as an antenna. - 14
Take the other end of the insulated wire back inside to the radio. Hook an alligator clip lead to the antenna, and the other end to one of the loops sticking out on the side of the container. - 15
Hook another alligator clip lead to the wire that comes out of the top of the container, and the other end to a cold water pipe or another metal object that leads into the ground. Do not under ANY circumstances use a live power line as a ground wire. - 16
Put the earpiece of the receiver up to your ear. You should be able to hear a radio station. Try picking up different stations by moving the alligator clip to different loops on the side of the container.
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