Crystal Radio

It’s super easy and fun to make a Crystal radio! Here’s a 49mtr (6 Mhz) SWL radio. Six parts — 1n34A diode, 24ga. wire, a T-37-6 torrid, a poly-varicon capacitor, 47K resistor, and a .001uf cap. Add a ground, a High Z headphone, and antenna and away you go.

If you want to be a little more sophisticated, You can add a galena crystal and a cat’s whisker, just like the original 1920’s radios, or maybe experiment with different diodes!

Below, I give the operator the options to select a single 1n34a, or two 1n34A’s, a BAT46, or a galena crystal. Secondly, the operator can select various taps on the coil and then use the poly-varicon variable capacitor to tune it in. Great fun to listen to a ball game on a Saturday afternoon. DX in the BC AM band is about 100 miles or 160 Km.

When you get the crystal radio bug, who knows where it will lead you. I got the cub scouts to build a backpack radio. They can use to keep up on the weather (WX) conditions when they are at camp. This unit is housed in an old cassette case. Using Fahnestock Clips, you can easily add a ground and antenna, and it works every time. High Z earphone goes across a 47k & .001uf cap. Of course, the antenna needs to be at least 75′ long.

Of course, these are very simple crystal sets that cover the AM BC band. If you want to see incredible works of art that really perform, check out Dave’s Homemade Crystal Radios for schematics and the state of art of the crystal radio!

Be warned, his site will mesmerize you and you too will need to build at least one crystal radio.

Mike

KD0ZW