Okay, but do military-grade systems use AM like this too? I imagine their needs aren't any less than those of civilians, and I imagine they've gotten their communication systems to work just fine. So what's the issue?
"Military-grade" systems use complicated techniques like frequency-hopping spread spectrum. They're designed to be encrypted and resistant to jamming. The jamming resistance is not something we care about (if someone is jamming the signal you just make them turn off their radio), and the whole point of encryption is to prevent interoperability when you don't have the right key.
So sure, you could pay a bunch of extra money for military features and end up with a product that is even less what you want than AM radio. And then you'd have to retrofit everything with these systems.
AM is wonderful. You put a bunch of people on the same channel and it just works.
> "Military-grade" systems use complicated techniques like frequency-hopping spread spectrum
Note that that technology has been around since World War II. And fun fact, while we're on that topic, this page is worth a read: https://en.wikipedia.org/wiki/Hedy_Lamarr
"The jamming resistance is not something we care about (if someone is jamming the signal you just make them turn off their radio)"
Evie might know this, too, so I think you should be concerned about jamming. Luckily, AM provides jamming resistance, since Evie would have to bring a powerful transmitter to be loud enough to drown out the other signals.
Nevertheless, I think large airports should have fast response teams who can rapidly fix the position of a jammer and silence it, if needed. If Evie could effectively take out, say, the main airports of LA and SF for a few hours with a few strong AM transmitters, I doubt all will end well.
Evie? I honestly have no idea who that is. But the more powerful the jamming, the easier it is to find the source. These days even hobbyists play around with cheap off-the-shelf RF analyzers and directional antennas, so I can't imagine that someone jamming airport signals would be able to evade arrest for very long.
I don't understand what is so wrong with the transmission quality in that MP3. The issues I hear sound like they are simply due to trying to transmit from an extremely noisy environment (the cockpit of an airplane); they are mitigating the pilot's voice being entirely drowned in the background noise by placing the microphone right next to their mouth, but that then causes the sound of their breath to be extremely noticeable. I am not sure how to fix these issues but they don't seem to have anything to do with the usage of AM radio.
I wasn't complaining about the transmission quality, I was just trying to understand the parent comment. The person who complained about the former was someone else.
Sorry; I misunderstood (and to be honest even after my tenth reread am still having a difficult time parsing...) the end of your comment about the "issue" :(.
OK, I'll clarify. Someone suggested non-AM transmission has problems X/Y/Z; I suggested that I expect non-AM transmission has overcome problems X/Y/Z in the military, and therefore I'm not convinced this is the real issue preventing non-AM communication. I was not discussing whether we or not we need non-AM communication in the first place.
Airlines don't need military systems which are used more for confidentiality and OPSEC than other things. In the field, militaries tend to avoid radio communications for various tactical reasons. Submarines are a great example of this.
Military-grade systems may not be any "less" but their needs and priorities may be different (e.g. secrecy). So different technology may be used, without any contradiction to why the current one is good for civilian air traffic.
So sure, you could pay a bunch of extra money for military features and end up with a product that is even less what you want than AM radio. And then you'd have to retrofit everything with these systems.
AM is wonderful. You put a bunch of people on the same channel and it just works.