How Do You Build A One Tube Crystal Radio?
Building a crystal radio for a Boy Scout merit badge or science fair project is not only a fun activity but a learning experience. Constructing a black box out of paper, wire and a piece of fool’s gold that captures electromagnetic waves and converts them into intelligible sound is an amazing accomplishment. Add a triode vacuum tube to run a speaker and the radio can be heard next door or far away. Purchase a simple crystal radio, prebuilt or a DIY kit. Assemble the kit.You can eliminate fussing with the “cat whisker” mount for the galena crystal (lead sulfide) and replace it with a diode. The object here is to have a working crystal radio. Attach the antenna system and a ground. Tune in to a strong local station. You can also use a schematic diagram available online. Some of the parts are homemade, such as the tank circuit that is the heart of the radio. Note that one radio uses a variable capacitor (365 pF) to tune the incoming radio signal, and the other uses a stationary capacitor
