The end of AM radio in your car? • Hacker News Board

Re: The end of AM radio in your car?

#21

Post by lormayna » Mon, Dec 05, 2022, 8:56 PM UTC

audiofish wrote: post #20

AM radio is a pretty poor standard considering how much power and bandwidth it uses, due much to the very limited modulation technology available in the 1920s. DRM (no not that DRM--Digital Radio Mondiale) is a modern digital standard that promises much better spectral efficiency, power efficiency and range. See https://www.drm.org/ . It is similar in concept to DAB, using an OFDM carrier, but with more robust error…

I am an huge fan of DRM, but the lack of receivers it's a good limitation for that.

Re: The end of AM radio in your car?

#22

Post by hulitu » Mon, Dec 05, 2022, 9:07 PM UTC

audiofish wrote: post #20

AM radio is a pretty poor standard considering how much power and bandwidth it uses, due much to the very limited modulation technology available in the 1920s. DRM (no not that DRM--Digital Radio Mondiale) is a modern digital standard that promises much better spectral efficiency, power efficiency and range. See https://www.drm.org/ . It is similar in concept to DAB, using an OFDM carrier, but with more robust error…

> and lower bit rate codec to handle larger broadcast areas

That's why DAB is crap. Because people are greedy and don't care about quality.

Re: The end of AM radio in your car?

#23

Post by audiofish » Mon, Dec 05, 2022, 9:27 PM UTC

hulitu wrote: post #22

audiofish wrote: post #20

AM radio is a pretty poor standard considering how much power and bandwidth it uses, due much to the very limited modulation technology available in the 1920s. DRM (no not that DRM--Digital Radio Mondiale) is a modern digital standard that promises much better spectral efficiency, power efficiency and range. See https://www.drm.org/ . It is similar in concept to DAB, using an OFDM carrier, but with more robust error…

> and lower bit rate codec to handle larger broadcast areas That's why DAB is crap. Because people are greedy and don't care about quality.

Agreed, but the alternative here is AM which has never been good quality. DAB was a big step down from FM quality because the choice of codec / bandwidth assigned to stations was pretty bad (and bandwidth == $$!)

Re: The end of AM radio in your car?

#24

Post by audiofish » Mon, Dec 05, 2022, 9:29 PM UTC

lormayna wrote: post #21

audiofish wrote: post #20

AM radio is a pretty poor standard considering how much power and bandwidth it uses, due much to the very limited modulation technology available in the 1920s. DRM (no not that DRM--Digital Radio Mondiale) is a modern digital standard that promises much better spectral efficiency, power efficiency and range. See https://www.drm.org/ . It is similar in concept to DAB, using an OFDM carrier, but with more robust error…

I am an huge fan of DRM, but the lack of receivers it's a good limitation for that.

That is true, although I know of one company close to production of a <10$ module for OEMs to integrate.

Re: The end of AM radio in your car?

#25

Post by cbm-vic-20 » Mon, Dec 05, 2022, 9:39 PM UTC

audiofish wrote: post #20

AM radio is a pretty poor standard considering how much power and bandwidth it uses, due much to the very limited modulation technology available in the 1920s. DRM (no not that DRM--Digital Radio Mondiale) is a modern digital standard that promises much better spectral efficiency, power efficiency and range. See https://www.drm.org/ . It is similar in concept to DAB, using an OFDM carrier, but with more robust error…

Obviously you know this, but AM is absurdly easy to implement. A pencil, razor blade, some wire and an earphone is all it takes to make a crude receiver.

https://en.wikipedia.org/wiki/Foxhole_radio

Re: The end of AM radio in your car?

#26

Post by andirk » Mon, Dec 05, 2022, 9:57 PM UTC

blacksmith_tb wrote: post #8

andirk wrote: post #5

Earlier quoted context omitted.

I wonder what "watch television" means these days. I don't know many people who have broadcast or cable TV.

Trending down slowly, but still 40% of US households: https://www.statista.com/statistics/612660/paid-services-bro...

What is historically the highest % of US households with TV?

(Paywall. And that is the most aggressive form I've ever battled.)

Re: The end of AM radio in your car?

#27

Post by no-dr-onboard » Mon, Dec 05, 2022, 10:31 PM UTC

What a shame. I've lived in a rural areas for most of my adult life. FM reception is notoriously poor due to the terrain. AM repeaters were always a nice touch. Also worth noting that AM radio content is absurdly easy to support and transmit.

Re: The end of AM radio in your car?

#28

Post by asdefghyk » Mon, Dec 05, 2022, 11:15 PM UTC

RE " ....That crackle apparently just doesn't fly with luxury auto brands. BMW spokesperson Rebecca Kiehne told me, "Electric motors cause interference on AM which is why BMW decided to remove this option. While it could be offered, BMW's performance standards are very high and we don't offer a product that meets less than those high standards."...." Apparently BMW *high standards do not extend to removing EMI* that interferes with AM. It could be done if they really wanted too.

Re: The end of AM radio in your car?

#29

Post by kjs3 » Mon, Dec 05, 2022, 11:46 PM UTC

cbm-vic-20 wrote: post #25

audiofish wrote: post #20

AM radio is a pretty poor standard considering how much power and bandwidth it uses, due much to the very limited modulation technology available in the 1920s. DRM (no not that DRM--Digital Radio Mondiale) is a modern digital standard that promises much better spectral efficiency, power efficiency and range. See https://www.drm.org/ . It is similar in concept to DAB, using an OFDM carrier, but with more robust error…

Obviously you know this, but AM is absurdly easy to implement. A pencil, razor blade, some wire and an earphone is all it takes to make a crude receiver. https://en.wikipedia.org/wiki/Foxhole_radio

Indeed. No way that replacing trivial to implement, ubiquitous communications technology with complicated, processing intensive, proprietary solutions could go wrong.

Re: The end of AM radio in your car?

#30

Post by Analemma_ » Tue, Dec 06, 2022, 12:14 AM UTC

stu2010 wrote: post #14

I haven't seen much discussion about how AM gets used for local road condition or emergency communication. When you're driving and see a sign that says "TUNE TO 1610 AM" and the car has no AM receiver, what do you do? This may be a shrinking niche, but it's potentially a last bastion of AM radio usefulness.

In a sample size of maybe 10, every time I’ve seen one of those highway signs and tuned to the station, the quality was so bad I couldn’t make out any words and so got no useful information. If that’s the last bastion of AM usefulness, scrap it and give that spectrum to the wireless carriers. Frankly, for stuff like road closure information I’m a lot more likely to get that from Waze (delivered over a 5G connection) now anyway.