[adrianN]

Digital only require better signal if you want high data rates. With analog signal the human has to do the error correction, i.e. extract the signal from the snowy picture. Digital signals can use error correcting codes to get the same result. The more bits you have for error correction, the better your recovery can be.

[dmitrygr]

With a lot of FEC, you can sort of approach it, but still not quite. Human brain is a lot better at picking out voice out of noise than any algorithm currently known. That is , for example, why your Alexa cannot take your commands in the middle of a 100-person party, but your interlocutor can hear you and respond.

[adrianN]

That is not very relevant since humans don't use an error correcting code that is easy to understand for machines when talking to each other. So Alexa's ability to filter your voice out of the noise has little to do with the ability of two machines understanding each other over a noisy channel when they use appropriate coding.

[mikeash]

I hate aircraft radios. I'm sure the guys in big planes have better equipment and don't suffer from this as much, but when I fly small planes, it's a complete mess of wildly different volume levels (it's fun to turn up the volume to hear a quiet person, then get blasted by the next transmission), interference, and irrelevant transmissions from a hundred miles away. Don't get me wrong, they get the job done and any change would have to be very carefully considered, but I'm always happy when I get far enough from the airport that I can turn the damned thing off.

I think a digital system could be done much better than what we have. But I'm sure it's not worth the huge effort it would take to design and build.

[Aloha]

This is a lack of AGC (automatic gain control) - usually even on the (shortwave and Ham) radios I've seen it on, its switchable, otherwise (in certain conditions, like rapid fading) you can end up with gain pumping, which can sound like the audio is surging.

What it normally does is reduce gain on high strength signals, and increases it on weak ones to give a constant volume level.

I'm honestly surprised the radios in general aviation craft are not so equipped, as its generally a standard part of most AM radios.

[mikeash]

Thanks, now I know what to look for next time I go equipment shopping. I'm sure many GA radios have this, but I'm using particularly low-end radios since space and power consumption are more important for what I do. Still won't fix getting an earful about skydivers at an airport a hundred miles away, but it would be an improvement!

[dmitrygr]

even KY-97A from decades ago handles this for you