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?<p>This may be a shrinking niche, but it's potentially a last bastion of AM radio usefulness.
This is the most interestingly line from his letter:<p>> nearly 90 percent of Americans ages 12 and older — totaling hundreds of
millions of people — listened to AM or FM radio each week, higher than the percentage that watch television (56 percent) or own a computer (77 percent)<p>Admittedly it seems dubious but if true I'm surprised by basically every one of these numbers
AM radio broadcasts can reach somewhat farther than FM (and way farther at night on clear channels); that might matter in an emergency.<p>As a middle-schooler living in the Washington DC area, I would regularly pick up WLS in Chicago, some 700 miles away, on my little crystal set at night.
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.<p>DRM (no not that DRM--Digital Radio Mondiale) is a modern digital standard that promises much better spectral efficiency, power efficiency and range. See <a href="https://www.drm.org/" rel="nofollow">https://www.drm.org/</a>. It is similar in concept to DAB, using an OFDM carrier, but with more robust error correction and equalisation, and lower bit rate codec to handle larger broadcast areas.<p>There is a hope that this could upgrade existing AM broadcast infrastructure, allowing rapid coverage of large areas without the expense of building out new towers.<p>The MW/HF bands are great for coverage because of the longer wavelength, relative to the VHF bands used for FM and DAB.
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 *<i>high standards do not extend to removing EMI*</i> that interferes with AM. It could be done if they really wanted too.
What exactly does he technically want to preserve? Does he really care about amplitude modulation? Or does he care about the frequency band (medium wave, HF) and its propagation properties? Or does he care bout the geographic reach of these stations?<p>Amplitude modulation is a historically important technology, because it was technically very simple to receive in the early history of radio, and because it was more bandwidth-efficient than FM. But it remains utterly badly suited for mobile reception, because it is highly sensitive for multi-path interference (unlike FM).<p>We have now far better modern, digital modulation schemes, including DAB and DVB-T2 for VHF and DRM for long, medium, and short-wave transmission. They provide (thanks to OFDM) much better audio quality and interference resistance than the old analogue modulation schemes, and they are also far more power efficient, which substantially reduces the enormous electricity bills of the transmitter stations. They also are very bandwidth efficient, and can be used in single-frequency networks.
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.
> The AM band in the United States covers frequencies from 540 kHz up to 1700 kHz<p>I wonder if there's something useful to do with that range. It's a big chunk of lower frequencies right there, in the range that reliably does over-the-horizon propagation (although better at night perhaps according to wikipedia?)<p>The benefit of AM being super simple to build a receiver for is less relevant nowadays, FM is trivial to get radios for now, and ham radio uses SSB for voice for the most part in the lower frequency ranges.
My favourite radio ever is AM 740 in the Boston area— WJIB, a listener-supported station broadcasting hits from the late 30s to 70s easy listening. Where else in broadcast these days can one expect to listen to the Dorsey Brothers, Glenn Miller, or Herb Alpert and his Tijuana Brass in the original AM sound? Good music for the soul.
I find it funny... here people are afraid their clients (cars) will lose AM support, and in europe, we feer the very-soon coming date when our governments will shut down FM radio, leaving a bunch of cars (those without DAB radios) musicless or tied to some kind of mobile phone connected to AUX ports situation.
After a recent hurricane decimated our area, a battery powered emergency AM radio was, for some time, the only source of information available. Communication resiliency shouldn't be decreased without good reason.
I still listen to AM radio (the CBC). (I mainly listen in the home, not in the car, because I do not have a car or a driving license; however, sometimes when going with someone else in the car, I can listen to radio.)<p>We need AM radio. AM radio is simple. It is better than having an overly complicated and badly made digital radio needing licensing and difficulty of implementation etc.
> Markey cited statistics from the Pew Research Center News Platform Fact Sheet from September 2022 which said 47% of Americans receive their news from the radio.<p>I believe that explains quite a bit. Without being snarky, AM radio is home to political opinion that is largely sympathetic to a conservative viewpoint and I suspect that is one reason that Markey wants car manufacturers to keep it (and why perhaps other lawmakers would be indifferent or even eager to see it disappear)<p>Not an adherent to the views commonly espoused on AM talk radio, I nevertheless see the utility for some kind of low-tech broadcast format which is easy and inexpensive to tune in and broadcast over. AM fits the bill, and has much longer range than FM