The Project Crystal Radio involvesthe construction, testing and operation of a series of crystal radios, starting witha very basic set and ending up with a medium performance dx set, completewith antenna tuner. In addition to thesuggested parts used here, you will also need a decent antenna and ground,preferably with alligator clips attached so you can fix them to your setswherever needed. Throughout, I selected parts based on availabilityand cost.
Paper towel rolls cores also are ok.
The two larger coils we will use areabout 400 uH each, and the capacitors will go from about 20 to 220 pF -enough to cover the AM broadcast band. If you want to play aroundwith different size coils, wire, capacitors, etc., go ahead if you knowhow to adjust. If not, I recommend you keep to the directions. First, let's lookat a picture of the completed base of the set and the two main coils youwill wind. The verticalstrips are the lath material, screwed to the 1 foot long base.