The classic crystal radio was an oatmeal box with some wire and a few parts. [Michael Simpson] has something very different. He found an assembled Philmore “selective” radio kit. The simple ...

This type of crystal radio design requires unbalanced antenna i.e. grounding must be of high quality (resistance of 10-100ohm) in order for radio to operate. Electronic circuit has been inspired by ...

Called a crystal radio receiver, or sometimes a “cat’s whisker receiver,” this is an incredibly simple type of radio receiver that was popular in the earliest days of radio.

The regenerative radio increases sensitivity and selectivity by operating at almost the point of oscillation, resulting in a surprisingly good receiver for so few parts.