8 ms·

Control EMI, Don’t Dump AM Receivers

49 points by maxerickson 4y ago

m463 4y ago
All of this stuff gets mismanaged. What I don't understand is why FM has been "modernized" by tying it up in proprietary transmission protocols (hd radio).
- JohnFen 4y ago
  Because large corporations are succeeding in figuring out how to privatize (steal) public resources.
superkuh 4y ago
I know they're talking about EMI and not radiated emissions but if even a tiny fraction of a fraction of the EMI does get radiated the widespread adoption of electrical vehicles will probably raise the noise floor in the HF bands significantly.
- londons_explore 4y ago
  Some of it will be radiated. Electric currents in EV's are typically in the hundreds of amps, and have potential switched by hundreds of volts in hundreds of nanoseconds. That leads to broad band emissions that aren't easy to shield. A bunch of ferrites and shielded motors and cables will help, but only to some extent.
  - shadowpho 4y ago
    >hundreds of nanoseconds Do you have any sources for this? Would love to learn more, as that seems extremely fast.
selflesssieve 4y ago
The electromagnetic sensors under the road for traffic lights also mess with AM reception in my non-electric car. Which in a city is a non-trivial amount of time.
- idonotknowwhy 4y ago
  Now I'm planning to try am radio next time I'm driving my car alone
1nverseMtx 4y ago
As someone that doesn’t listen to radio a lot, but when I do it’s FM only what do we loose without AM? This article doesn’t give a single reason to argue why AM should be preserved.
- throw0101a 4y ago
  See "Ford to drop AM radio in new models, except commercial vehicles": * https://news.ycombinator.com/item?id=35416627 https://news.ycombinator.com/item?id=35416627 Generally traffic/weather/emergency information, especially less populated regions, and remote regions (e.g., mountains) that get no other kind of signal. Various DOTs have AM radio transmitters for PSAs.
  - officeplant 4y ago
    >Various DOTs have AM radio transmitters for PSAs. Yep, we've got hurricane routing signs everywhere that also mention what frequency to tune into.
- rnmmrnm 4y ago
  In some regions of the world AM is all you can find.
- don-code 4y ago
  My take is that the article argues for keeping it on the grounds of technical merit, not of purpose. Senator Ed Markey makes (https://www.markey.senate.gov/imo/media/doc/letter_to_automakers_on_am_radio_-_december_2022.pdf https://www.markey.senate.gov/imo/media/doc/letter_to_automa...) some better points about it: > Broadcast AM radio remains a crucial, cost-free source of news, sports, and weather, and, more importantly, is an essential medium for public safety officials — including the president — to communicate with the public during emergencies, There are several "clear channel" AM radio stations in the United States - that is, they are guaranteed no interference from FCC assignments to other stations elsewhere in the country, unlike the majority of stations which share the spectrum based on their geographic location. Because of that, they're allowed to broadcast at power levels considerably higher than other stations. This makes clear channel stations incredibly useful in the event of a public emergency (war, natural disaster, etc.). WBZ is based out of Sen. Markey's home state of Massachusetts - specifically a suburb of Boston - and I've personally been able to pick it up as far away as Erie, Pennsylvania.
BoxOfRain 4y ago
It's a moot point in the UK at least, sadly we're binning off even the mighty Radio 4 longwave signal in a year or so as part of the latest round of cost-cutting measures at the BBC. Most of the British stations have already shut down their AM output with Absolute Radio being the latest to pull the plug. What I'd love to see is the top part of the medium wave band being opened to broadcasting hobbyists along similar lines to radio amateurs on the technical side and internet radio stations (who can get a licence for small-scale music streaming here) on the copyright side. You can hear a few pirates on AM today mostly from the Netherlands but a minority from the UK around and just over the top of MW. If there's no more state nor commercial use of AM I think legitimising these hobbyist stations would be a good use of that spectrum which isn't going to be useful for much else given how full of interference it is anyway. It would be nice from a reducing e-waste angle, not to mention the 'living history' aspect of keeping old radios working. Lots of hobbyist interests could converge here. There might even be limited mainstream appeal, weirder things have happened with even cassettes getting a limited revival in some circles.
- fredoralive 4y ago
  With regards to the BBC Radio 4 Longwave service going away, I really hope that they've told the Royal Navy about it, otherwise we could end up with the lamest cause for a nuclear apocalypse ever.
  - knodi123 4y ago
    Some say the world will end in fire, Some say in ice. But I say idiotic bureaucracy.
- dylan604 4y ago
  >What I'd love to see is the top part of the medium wave band But why? These are only discoverable by people making "small movies Ellie, small moves". It would be much more beneficial to wannabe pirate radio types to just create a channel via internet. You can still be a pirate by not joining Spotify et al, and just have a set of rogue servers that people can connect to pull the stream. The point of pirate radio was to get music to the masses that regular stations wouldn't broadcast. Why? Because that's where the audience was. If there's no audience, why expend the energy? Go to where the audience is.
arbitrage 4y ago
I have not heard a single affirmative reason to keep AM in cars as a technology at this late a date. I look forward to finally hearing one ... some day.
- Czarcasm 4y ago
  In rural areas with no cell service, AM radio is often the only available form of weather and news. It's also a great form of emergency information broadcasting in the event of a natural disaster.
  - msla 4y ago
    There might be a silver lining to the slow death of commercial terrestrial radio: Doing away with the polite fiction that commercial terrestrial radio is a valid way to communicate emergency information. Even if the "local" radio stations are active and broadcasting a signal, they're often only local in a way that does not matter when it comes to emergency broadcasts: https://en.wikipedia.org/wiki/Minot_train_derailment https://en.wikipedia.org/wiki/Minot_train_derailment > The Minot train derailment occurred just west of Minot, North Dakota, United States, on January 18, 2002, when a Canadian Pacific Railway freight train derailed, spreading ammonia gas across the city, delaying rescue operations. The cause was found to be small fatigue cracks in the rails and joint bars, not detectable by the inspection routines then enforced by Canadian Pacific. [snip] > Because it was the middle of the night, there were few people at local radio stations, all operated by Clear Channel with mostly automated programming. No formal emergency warnings were issued for several hours while Minot officials located station managers at home. North Dakota's public radio network, Prairie Public Broadcasting, was notified and did broadcast warnings to citizens. Public radio succeeded. Commercial radio did not. People have been utterly resistant to learning this lesson. Maybe once commercial radio is dead they'll have no other choice.
    - JohnFen 4y ago
      > Doing away with the polite fiction that commercial terrestrial radio is a valid way to communicate emergency information. It may suck for that, but it's the best choice out of a whole bunch of bad alternatives. What would do this better?
ltbarcly3 4y ago
Do both! Recapture AM spectrum for use cases that aren't wasteful and dead, reduce EMI because harmful interference is a bad thing and limits our future options for using spectrum.
- deleted 4y ago
  [deleted]
- UncleEntity 4y ago
  Broadcasting information over great distances using radio waves is wasteful?
  - mike50 4y ago
    When done with 1920s era power hungry analog transmission systems maybe.
manv1 4y ago
Look at all that spectrum that can be repurposed if AM radio went away! https://ntia.gov/sites/default/files/publications/january_2016_spectrum_wall_chart_0.pdf https://ntia.gov/sites/default/files/publications/january_20...
- ocal5 4y ago
  Oh, yeah, that’s a full megahertz here!
wkdneidbwf 4y ago
i’d rather ditch AM radio in the car than pay more for better shielding, design, etc. i mean, i’d prefer both, but i think it’s likely either-or. i neeeevvvveeer listen to AM. maybe there’s some value in emergencies, but i had a different radio for that so having it in my car isn’t important.
timmaxw 4y ago
I think it's important to be able to receive emergency broadcasts, including in areas with no cell service. Could those emergency broadcasts be moved to FM, though? Or is there something about AM that makes it more suitable for emergency broadcasts?
- vitaflo 4y ago
  AM travels much farther at lower power levels, especially at night. As such one could cover a wider area with less power when perhaps power is in limited supply.
Analemma_ 4y ago
I've seen a couple of these articles about how EV makers should add EMI shielding so they can have AM radio, and I notice that all of them steer around the issue of how much it would cost. If it adds $1 to the price of the car, sure, but if it adds $100, no way. We need EVs to be as affordable as possible to spur adoption; adding a bunch of cost for the take of a technology which-- let's be perfectly honest here-- hardly anybody uses, is a terrible tradeoff.
- olyjohn 4y ago
  I can think of about 50,000 things we can remove from EVs to make them cheaper. I can't believe out of all the things they put into an EV, removing AM radio is the one thing that will make them cheaper. Does everybody need all of the infotainment shit? No. But will they make an EV without one? No. Most infotainment setups suck ass, but everybody still wants one so bad. Most factory stereos are total crap, even the branded, "good" ones. Does everybody need 1200lb-ft of torque? Dual motors? Massaging, heated, seats, and whale penis leather? AWD that you use maybe one time per year, when you should probably stay home anyways? The manufacturers here are chasing profits, not trying to make affordable cars. They're not going to pull out the AM radio and pass the savings on to you. Nobody ever passes the savings on to you.
- JohnFen 4y ago
  > We need EVs to be as affordable as possible to spur adoption If that's the argument for removing AM, then let's start with all of the other, much more expensive, things that tend to annoy people and that can be removed first. $100 is peanuts.

49 points by maxerickson 4y ago

m463 4y ago

All of this stuff gets mismanaged. What I don't understand is why FM has been "modernized" by tying it up in proprietary transmission protocols (hd radio).

JohnFen 4y ago
Because large corporations are succeeding in figuring out how to privatize (steal) public resources.

superkuh 4y ago

I know they're talking about EMI and not radiated emissions but if even a tiny fraction of a fraction of the EMI does get radiated the widespread adoption of electrical vehicles will probably raise the noise floor in the HF bands significantly.

londons_explore 4y ago
Some of it will be radiated. Electric currents in EV's are typically in the hundreds of amps, and have potential switched by hundreds of volts in hundreds of nanoseconds. That leads to broad band emissions that aren't easy to shield. A bunch of ferrites and shielded motors and cables will help, but only to some extent.
- shadowpho 4y ago
  >hundreds of nanoseconds Do you have any sources for this? Would love to learn more, as that seems extremely fast.

selflesssieve 4y ago

The electromagnetic sensors under the road for traffic lights also mess with AM reception in my non-electric car. Which in a city is a non-trivial amount of time.

idonotknowwhy 4y ago
Now I'm planning to try am radio next time I'm driving my car alone

1nverseMtx 4y ago

As someone that doesn’t listen to radio a lot, but when I do it’s FM only what do we loose without AM? This article doesn’t give a single reason to argue why AM should be preserved.

throw0101a 4y ago
See "Ford to drop AM radio in new models, except commercial vehicles": * https://news.ycombinator.com/item?id=35416627 https://news.ycombinator.com/item?id=35416627 Generally traffic/weather/emergency information, especially less populated regions, and remote regions (e.g., mountains) that get no other kind of signal. Various DOTs have AM radio transmitters for PSAs.
- officeplant 4y ago
  >Various DOTs have AM radio transmitters for PSAs. Yep, we've got hurricane routing signs everywhere that also mention what frequency to tune into.
rnmmrnm 4y ago
In some regions of the world AM is all you can find.
don-code 4y ago
My take is that the article argues for keeping it on the grounds of technical merit, not of purpose. Senator Ed Markey makes (https://www.markey.senate.gov/imo/media/doc/letter_to_automakers_on_am_radio_-_december_2022.pdf https://www.markey.senate.gov/imo/media/doc/letter_to_automa...) some better points about it: > Broadcast AM radio remains a crucial, cost-free source of news, sports, and weather, and, more importantly, is an essential medium for public safety officials — including the president — to communicate with the public during emergencies, There are several "clear channel" AM radio stations in the United States - that is, they are guaranteed no interference from FCC assignments to other stations elsewhere in the country, unlike the majority of stations which share the spectrum based on their geographic location. Because of that, they're allowed to broadcast at power levels considerably higher than other stations. This makes clear channel stations incredibly useful in the event of a public emergency (war, natural disaster, etc.). WBZ is based out of Sen. Markey's home state of Massachusetts - specifically a suburb of Boston - and I've personally been able to pick it up as far away as Erie, Pennsylvania.

BoxOfRain 4y ago

It's a moot point in the UK at least, sadly we're binning off even the mighty Radio 4 longwave signal in a year or so as part of the latest round of cost-cutting measures at the BBC. Most of the British stations have already shut down their AM output with Absolute Radio being the latest to pull the plug. What I'd love to see is the top part of the medium wave band being opened to broadcasting hobbyists along similar lines to radio amateurs on the technical side and internet radio stations (who can get a licence for small-scale music streaming here) on the copyright side. You can hear a few pirates on AM today mostly from the Netherlands but a minority from the UK around and just over the top of MW. If there's no more state nor commercial use of AM I think legitimising these hobbyist stations would be a good use of that spectrum which isn't going to be useful for much else given how full of interference it is anyway. It would be nice from a reducing e-waste angle, not to mention the 'living history' aspect of keeping old radios working. Lots of hobbyist interests could converge here. There might even be limited mainstream appeal, weirder things have happened with even cassettes getting a limited revival in some circles.

fredoralive 4y ago
With regards to the BBC Radio 4 Longwave service going away, I really hope that they've told the Royal Navy about it, otherwise we could end up with the lamest cause for a nuclear apocalypse ever.
- knodi123 4y ago
  Some say the world will end in fire, Some say in ice. But I say idiotic bureaucracy.
dylan604 4y ago
>What I'd love to see is the top part of the medium wave band But why? These are only discoverable by people making "small movies Ellie, small moves". It would be much more beneficial to wannabe pirate radio types to just create a channel via internet. You can still be a pirate by not joining Spotify et al, and just have a set of rogue servers that people can connect to pull the stream. The point of pirate radio was to get music to the masses that regular stations wouldn't broadcast. Why? Because that's where the audience was. If there's no audience, why expend the energy? Go to where the audience is.

arbitrage 4y ago

I have not heard a single affirmative reason to keep AM in cars as a technology at this late a date. I look forward to finally hearing one ... some day.

Czarcasm 4y ago
In rural areas with no cell service, AM radio is often the only available form of weather and news. It's also a great form of emergency information broadcasting in the event of a natural disaster.
- msla 4y ago
  There might be a silver lining to the slow death of commercial terrestrial radio: Doing away with the polite fiction that commercial terrestrial radio is a valid way to communicate emergency information. Even if the "local" radio stations are active and broadcasting a signal, they're often only local in a way that does not matter when it comes to emergency broadcasts: https://en.wikipedia.org/wiki/Minot_train_derailment https://en.wikipedia.org/wiki/Minot_train_derailment > The Minot train derailment occurred just west of Minot, North Dakota, United States, on January 18, 2002, when a Canadian Pacific Railway freight train derailed, spreading ammonia gas across the city, delaying rescue operations. The cause was found to be small fatigue cracks in the rails and joint bars, not detectable by the inspection routines then enforced by Canadian Pacific. [snip] > Because it was the middle of the night, there were few people at local radio stations, all operated by Clear Channel with mostly automated programming. No formal emergency warnings were issued for several hours while Minot officials located station managers at home. North Dakota's public radio network, Prairie Public Broadcasting, was notified and did broadcast warnings to citizens. Public radio succeeded. Commercial radio did not. People have been utterly resistant to learning this lesson. Maybe once commercial radio is dead they'll have no other choice.
  - JohnFen 4y ago
    > Doing away with the polite fiction that commercial terrestrial radio is a valid way to communicate emergency information. It may suck for that, but it's the best choice out of a whole bunch of bad alternatives. What would do this better?

ltbarcly3 4y ago

Do both! Recapture AM spectrum for use cases that aren't wasteful and dead, reduce EMI because harmful interference is a bad thing and limits our future options for using spectrum.

deleted 4y ago
[deleted]
UncleEntity 4y ago
Broadcasting information over great distances using radio waves is wasteful?
- mike50 4y ago
  When done with 1920s era power hungry analog transmission systems maybe.

manv1 4y ago

Look at all that spectrum that can be repurposed if AM radio went away! https://ntia.gov/sites/default/files/publications/january_2016_spectrum_wall_chart_0.pdf https://ntia.gov/sites/default/files/publications/january_20...

ocal5 4y ago
Oh, yeah, that’s a full megahertz here!

wkdneidbwf 4y ago

i’d rather ditch AM radio in the car than pay more for better shielding, design, etc. i mean, i’d prefer both, but i think it’s likely either-or. i neeeevvvveeer listen to AM. maybe there’s some value in emergencies, but i had a different radio for that so having it in my car isn’t important.

timmaxw 4y ago

I think it's important to be able to receive emergency broadcasts, including in areas with no cell service. Could those emergency broadcasts be moved to FM, though? Or is there something about AM that makes it more suitable for emergency broadcasts?

vitaflo 4y ago
AM travels much farther at lower power levels, especially at night. As such one could cover a wider area with less power when perhaps power is in limited supply.

Analemma_ 4y ago

I've seen a couple of these articles about how EV makers should add EMI shielding so they can have AM radio, and I notice that all of them steer around the issue of how much it would cost. If it adds $1 to the price of the car, sure, but if it adds $100, no way. We need EVs to be as affordable as possible to spur adoption; adding a bunch of cost for the take of a technology which-- let's be perfectly honest here-- hardly anybody uses, is a terrible tradeoff.

olyjohn 4y ago
I can think of about 50,000 things we can remove from EVs to make them cheaper. I can't believe out of all the things they put into an EV, removing AM radio is the one thing that will make them cheaper. Does everybody need all of the infotainment shit? No. But will they make an EV without one? No. Most infotainment setups suck ass, but everybody still wants one so bad. Most factory stereos are total crap, even the branded, "good" ones. Does everybody need 1200lb-ft of torque? Dual motors? Massaging, heated, seats, and whale penis leather? AWD that you use maybe one time per year, when you should probably stay home anyways? The manufacturers here are chasing profits, not trying to make affordable cars. They're not going to pull out the AM radio and pass the savings on to you. Nobody ever passes the savings on to you.
JohnFen 4y ago
> We need EVs to be as affordable as possible to spur adoption If that's the argument for removing AM, then let's start with all of the other, much more expensive, things that tend to annoy people and that can be removed first. $100 is peanuts.