4
$\begingroup$

I know single sideband is much better than FM for weak signal receiving. I know that SSB is just like AM, but with the unneeded parts removed.

For weak signal propagation, like EME and aurora, would reception on AM or SSB be better?

$\endgroup$
  • 2
    $\begingroup$ As far as I know, more people do EME and Aurora with CW or JT65 or any similar close-to-the-background-noise level digital mode, than do it with voice. $\endgroup$ – Warren VE3WPX Mar 7 '14 at 22:23
7
$\begingroup$

I don't think anyone would be transmitting AM for weak signal work unless they were just fooling around. You'd get the same effect by cutting your power by 3/4s. In AM the carrier consumes 1/2 the power with the rest split between the side bands. So, SSB is not only more efficient use of spectrum, it's more effective use of your power.

$\endgroup$
  • $\begingroup$ You also have at least twice the bandwidth (and consequently noise received) on the receiver end, because to actually receive AM you need twice the sideband bandwidth, rather than the sideband bandwidth as for SSB. So not only are you effectively cutting your useful transmit power by 6 dB through the carrier and double sideband nature of AM, you're also battling an additional 3 dB of noise on receive due to the wider receive bandwidth, for a total S/N reduction of 9 dB. That's a lot of S/N especially for weak-signal work. $\endgroup$ – user Jun 4 '14 at 21:55

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.