NationStates Jolt Archive

Ok, this has been perplexing me for awhile. How come the reception of AM freq are crappy and moderate at best, and always get interference from other things giving off radio and electrical signals, however the FM reception is always clear as a bell unless you're outside the reception radius? Also, how come my favorite AM station won't convert to FM so I can actually hear their quality programming without all the interference?

http://en.wikipedia.org/wiki/AM_broadcasting

http://www.geocities.com/richleebruce/amradio.html

the various licenses, equipment, and misc. are cheaper for AM than FM which is probably why they won't switch.


some AM stations do online streaming.

Ok, this has been perplexing me for awhile. How come the reception of AM freq are crappy and moderate at best, and always get interference from other things giving off radio and electrical signals, however the FM reception is always clear as a bell unless you're outside the reception radius? Also, how come my favorite AM station won't convert to FM so I can actually hear their quality programming without all the interference?

Possibly because the other things are giving off interference in an amplitude modulated way (AM)?

And your station won't convert because there probably isn't a spare FM frequency for it to use.

AM radio has better range, iirc.

Ok, this has been perplexing me for awhile. How come the reception of AM freq are crappy and moderate at best, and always get interference from other things giving off radio and electrical signals, however the FM reception is always clear as a bell unless you're outside the reception radius? Also, how come my favorite AM station won't convert to FM so I can actually hear their quality programming without all the interference?Because FM has a higher data transfer rate than AM.

You can find a lot of interferrence with AM, including car engines :), especially on CB radios.

Ok, this has been perplexing me for awhile. How come the reception of AM freq are crappy and moderate at best, and always get interference from other things giving off radio and electrical signals, however the FM reception is always clear as a bell unless you're outside the reception radius? Also, how come my favorite AM station won't convert to FM so I can actually hear their quality programming without all the interference?

AM is far lower on the band. 520-1600 Kilo hz

FM is at 88-108 Mega hz

Also AM changes the amplitude (height) of the waves.

FM changes the frequency (number of waves)

Because of this AM tends bounce on the atmosphere and thereby to follow the curve of the earth and so goes further. FM is basically "line of sight". In other words, if you were standing at the top of the tower you could look out and see everything that you cover. Beyond that sight the waves go into outer space.

Because the atmosphere effects AM any variations in the atmosphere will effect AM.

There is only so many bands so all of the AM's can't convert to FM. And in rural areas AM is still useful because it covers so much more land.

Because voice isn't as sensitive as music many AM's have gone to "talk radio" in order to compete.