|[AMRadio] RE:Carrier with one sideband|
k4kyv at charter.net
Fri Feb 8 19:10:09 EST 2008
> I seem to remember that the aircraft radios we used during the 60-80s in
> P-3s/C-130s etc (ARC-94/102 aka 618T) had a
> selection called AME (AM equivalent). It was explained to us (pilots)
> by the techs that it wasn't a
> high level AM, but USB with carrier. It sounded OK, but then again, it
> was designed for communications
> and not "easy listening"! All the airways communication now days is
> SSB, so the AME position rarely
> gets selected.
> Perhaps someone is familiar with that mode and can expand on it.
> 73 Tom/W4OKW
Aircraft VHF radios still use full carrier AM. I have a small Radio Shack
portable with the aircraft band, and there is a lot of AM traffic on it. I
purchased it mainly to use as a tool for sniffing out power line noise. The
reason they use AM instead of FM is the capture effect of FM. With AM, when
a strong signal is on frequency, a weaker one can still be heard under the
stronger one. It would be a catastrophe waiting to happen if aircraft used
FM radios and a stronger signal completely overrode, particularly near a
busy airport. Also, I seem to recall something about SSB being less than
satisfactory due to the shift in frequency due to the Doppler effect, with
high speed jet aircraft.
More information about the AMRadio mailing list
This page last updated 12 Dec 2017.