This is the simplest radio ever! It's a pared-down version of a fixed-frequency crystal set, consisting of one inductor and one diode. Nothing else.

The switch merely selects the other inductor, and so, an alternative frequency. Both are optional.

First up, is BBC Radio 4, broadcast from the longwave transmitter in Droitwich, around 120km distant. Secondly, you'll hear China Radio International from their Kashi-Saibagh outlet, some 5500km away.

The aerial is a random piece of wire, about 30m long, in the garden. And the earth connection is a croc-clip to the radiator.

For the purpose of this demonstration, the crystal set was connected directly to the PC's line-in socket and recorded with Adobe Audition. There is no audio filtering, and quality - I think - is impressive.

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