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A comment on Congress fights to keep AM radio in cars. Parent comment

Re:Congress fights to keep AM radio in cars by evanjrowley on Sunday October 06, 2024 @10:51PM (#41762354)
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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Re:Congress fights to keep AM radio in cars by vel0city on Sunday October 06, 2024 @11:04PM (#41762410)
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).

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Re:Congress fights to keep AM radio in cars by carlmr on Monday October 07, 2024 @04:03AM (#41763751)
>you're pretty close to a quarter wave with a normal headphone wire (~3ft)

You mean half-wave, right?

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Re:Congress fights to keep AM radio in cars by boomlinde on Monday October 07, 2024 @06:44AM (#41764681)
3.5 m is almost 12 feet, so 3 feet is almost a quarter wave.
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Re:Congress fights to keep AM radio in cars by carlmr on Monday October 07, 2024 @11:20AM (#41766892)
Ah, my bad, didn't convert feet properly in my head. Not used to it.
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Re:Congress fights to keep AM radio in cars by vel0city on Monday October 07, 2024 @11:35AM (#41767056)
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!

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Re:Congress fights to keep AM radio in cars by spunker540 on Sunday October 06, 2024 @11:16PM (#41762461)
Can we still have AM radio via usb c?
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