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Many cellphones could receive AM and FM radio through the 3.5mm headphone jack, before it was eliminated from most devices. It was possible, but people just never talked about it. You can't even find search results because the idea is so alien to most people in search engines.

Example: https://xdaforums.com/t/diy-fm-antenna-with-3-5mm-audio-jack...

If only we had legislation to bring those back...

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AM radio reception on a headphone wire is pretty bad. I've had a few small radios designed to get commercial AM/FM using the headphones as antennas; the reception is almost always very miserable.

Meanwhile commercial FM is like ~3.5M wavelength; you're pretty close to a quarter wave with a normal headphone wire (~3ft).

>you're pretty close to a quarter wave with a normal headphone wire (~3ft)

You mean half-wave, right?

3.5 m is almost 12 feet, so 3 feet is almost a quarter wave.

Ah, my bad, didn't convert feet properly in my head. Not used to it.

I'll take half the blame for using such measures interchangeably in a single sentence.

The metric system is the tool of the devil! My car gets forty rods to the hogshead and that's the way I likes it!

Can we still have AM radio via usb c?

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