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Comment by pierrec | Hacker News Reader

"Different results will be achievable with different equipment. Please send your results to sbr@phor.net"

I think the barrier to entry for this is raised by the fact that most people don't have AM receivers anymore. If I find one lying around though, I will certainly give this a try.

Ah, and apparently this proof-of-concept works exclusively on OSX for now.

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Almost all cars still have them, just bring a laptop into a car.

BMW i3 has the AM hardware builtin but disabled it in firmware [1] due to the exact same reason: electromagnetic interferences caused poor quality of the AM reception.

Obviously, AM radio on i3s can be re-enabled by firmware hacking - called "coding". [2]

Even with the full metal body/frame, AM radio noise caused by EMI emitted from EV motor/circuits was still significant. I guess it's still VERY HARD to shield these EMIs.

Full disclosure: I've owned BMW ActiveE and BMW i3.

[1] http://www.greencarreports.com/news/1098893_bmw-i3-electric-...

[2] http://www.greencarreports.com/news/1099782_bmw-i3-rex-elect...

The Tesla Model S has AM. It's fun to tune the radio to an unused frequency and drive around. The radio picks up a ton of noise that sort of emulates just a little bit how a loud gasoline engine would sound.

I hear that they've removed AM from the Model X.

   The radio picks up a ton of noise that sort of emulates just a little bit how a loud gasoline engine would sound.

It's the same behavior in BMW EVs(i3/i8/ActiveE/MiniE). It's not a constant noise on AM radio but really when you press the accelerator pedal hard on a quiet street could you hear the interference. BMW consider that unacceptable based on their "standards".

Apparently a lot ofTesla Model S owners agree with BMW on the subpar AM radio reception and complaint on their forum[1], which was probably why AM radio removed from Model X. I do consider that a surprise feature (of emulating engine revs) albeit it's a bit annoying sometimes.

[1] https://forums.teslamotors.com/forum/forums/am-radio-station...

Funny that alternator whine is the bane of all car audio installers and a similar thing is a feature in EVs :)

The Mitsubishi Outlander PHEV have an AM radio, and while there is some interference it's actually not much except on a few frequences. I admit that I spent quite a while searching for the most amount of noise.

It's slightly non-trivial to even shield modern car audio system itself from interfering with it's own AM receiver. It involves things like dynamically scaling various clocks to be outside of the currently tuned AM channel and so on.

Do they give you some alternative way to listen to AM stations?

I find AM stations very useful for traffic/weather while traveling. Also for road notices.

I had assumed it was mandated that cars in the USA have AM radios so that they could listen to TIS stations. https://en.wikipedia.org/wiki/Travelers'_information_station

I can't find anything that enforces that mandate, though. So I guess there's nothing keeping you from shipping a car radio without AM.

This is crazy, so many people have SDR but not AM radios! FYI car radios did not work for me, maybe because they have better shield. Also, I understand that someone has translated this to linux APIs but have not seen a PR yet.

Just did a PR right after you posted the message :)

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