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Comment by arwineap | Hacker News Reader

I think that ssb is great but it targets bands of radius around you

I'm not sure AM has the same issues

Here's a chart that illustrates skywave bounce

    2 MHz 200-400 miles
    4 MHz 400-600 miles
    6 MHz 600-1,200 miles
    8 MHz 800-1,600 miles
    12 MHz 1,200-2,400 miles
    16 MHz 1,600-3,200 miles
    22 MHz 2,200-4,000 miles plus
    26 MHz unpredictable during our solar cycle minimum

But of course any of that is completely independent of whether using SSB or not. Modulation used doesn't really change wave characteristics to such significant extent. It's just that SSB is much more effective, this way or another, so it will probably get used in cases like that.

"Modulation used doesn't really change wave characteristics to such significant extent,"

True, except when the ionosphere is changing rapidly and phases change across the bandwidth (as in fading). SSB helps and it's really great for narrow band comms but without the carrier the demodulated audio has pitch problems. Not an issue for basic comms but it is if audio has to be on frequency.

SSB reduced carrier and synchronous detection is another solution.

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