A recent test of the emergency alert system found only 1 percent got it via AM.
A controversial bill that would require all new cars to be fitted with AM radios looks set to become a law in the near future. Yesterday, Senator Edward Markey (D-Mass) revealed that the "AM Radio for Every Vehicle Act" now has the support of 60 US Senators, as well as 246 co-sponsors in the House of Representatives, making its passage an almost sure thing. Should that happen, the National Highway Traffic Safety Administration would be required to ensure that all new cars sold in the US had AM radios at no extra cost.
AM Radio has an extremely important role in emergency broadcasting, because you can cover a whole continent using just 3-4 broadcasting stations, and it is so easy to demodulate, that you can build completely analog recievers that need no power source (they use the carrier wave as a power source).
This also means that AM receivers are very cheap, so in a lot of developing countries the only broadcasts most people can afford, and will reach them are AM.
I think we should keep AM radio around, at least for emergencies.
Also, unfortunately, when HF bandwidth gets freed up, it mostly ends up going to companies that use it for high frequency trading, and not to things where it would benefit the public, like ham radio, or digital broadcasts.
Yeah let's keep flooding old noise into the airwaves rather than update just so you don't have to acknowledge you're getting older and the world is changing.
Go use a 14.4 baud modem if you like obsolete communication protocols so much.
I also don't have much knowledge here, but I don't think much.
I guess the wavelength differences on HF and below would be too large for something of larger bandwidth. And anyway, the AM broadcast bands aren't that large anyway. Plus there would still be too much RFI from foreign broadcasts.
My idea is, it could perhaps be upgraded to DRM. But this is used very rarely since it requires DRM-compatible receivers.
But personally, I don't think this would be a better idea than AM. Having to get new receivers for over-compressed digital audio? Nah.
Second, probably not the best idea, some of those could be license-free bands. E.g. for LoRa. Imagine Meshtastic on HF.
My understanding is that the EU -- higher density, more languages (so more radio stations that nearby people can't use), more-congested radio spectrum -- has done this, forced a switch to digital car radios, and has generally placed more weight on ways to acquire more usable bandwidth.
The US, without the same level of pressure for the frequency spectrum, has placed a higher priority on not breaking compatibility, keeping existing devices continuing to function.
In the European Union, "the European Electronic Communications Code (EECC) entered into force on 20 December 2018, with transposition into national legislation by Member States required by 21 December 2020. The Directive applies to all EU member states regardless of the status of DAB+ in each country. This means that since the end of 2020, across all EU countries, all radios in new cars must be capable of receiving and reproducing digital terrestrial radio."