"David" wrote in message
...
AM is a bandwidth hog and way too sensitive to interference. I can
see why the FAA likes it on VHF (you can hear both transmitters if 2
light-up at the same time) but for entertainment delivery I'm afraid
the light dimmers and touch lamps are winning.
How is AM a bandwidth hog? Standard AM on SW is about 10khz wide. For
communicaton puropses, 3khz SSB is adequate. DRM is also in a 10khz
channel, but it's interference potential is much worse than AM because it's
energy is more evenly distributed across the channel, while there's usually
little high frequency energy in a an AM channel with normal programming.
You have a point about the interference problems with AM, but touch lamps,
light dimmers and switchmode power supplies can be made much cleaner for
little more expense. Electrically clean products are available right now.
If interference ever becomes much of an issue for most people, it would be
easier and cheaper to enforce existing Part 15 rules, rather than force
everyone to buy a new radio.
Frank Dresser
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