It’s then a simple matter of hooking up the right pads on the credit card to the rest of a crystal radio circuit, and you’re all set. Of course, [Billy] goes the whole hog, building the entire ...

The classic crystal radio was an oatmeal box with some wire ... built on a wooden substrate with a very basic coil and capacitor tuned circuit. The model VC-1000 appears to be about 60 years ...