Vintage Crystal Radio Draws the Waves [Hackaday]

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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 kit had a coil, a germanium diode, and a crystal earphone.

We were sad when [Michael] accidentally burned a part of the radio’s coil. But–well–in the end, it all worked out. We’ll just say that and let you watch for yourself. The radio is simplicity itself, built on a wooden substrate with a very basic coil and capacitor tuned circuit.

The model VC-1000 appears to be about 60 years old, and back then, it cost $5. That doesn’t sound like much, but that’s about $50 in today’s money. Of course, a nice one in mint condition today would probably be worth a good bit more than $50.

[Michael] uses an amplifier to let us listen in, but the original crystal earphone has to have a high impedance to prevent loading the detector. At first, there was an intermittent connection to the radio, perhaps not surprising after 60 years for a $5 radio.

The variable capacitor had metal plates with what looked like mylar spacers. The capacitor plates intermittently shorted, probably due to damage to the spacers. He did take the cap apart and found the root cause of the issue. Watching him reassemble it was oddly calming.

A “new” capacitor finally arrived. After a little surgery, the radio was back to its original condition. It always seems like magic that just some wire, metal plates, and a little glass-like cylinder is all you need to hear signals that fly through the air.

While crystal radios tend to be simple, that’s not always true. They can also be a lot smaller.