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Old July 1st 07, 03:24 PM posted to sci.electronics.basics,rec.radio.shortwave,rec.radio.amateur.antenna,alt.cellular.cingular,alt.internet.wireless
[email protected] shawn.cormican@gmail.com is offline
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First recorded activity by RadioBanter: Jul 2007
Posts: 3
Default AM electromagnetic waves: 20 KHz modulation frequency on an astronomically-low carrier frequency

On Jun 30, 2:55 pm, John Smith I wrote:
Radium wrote:

...


I am getting conflicting answers. Some say it's possible to modulate a
carrier frequency at a frequency higher than the carrier frequency,
others say it isn't.


Who is right?


Radium:

Use simple logic, you can modulate a dc (0 Hz) with higher freq (voice),
(hint, your telephone line is an example) right?

However, when you get into RF--possible, usable, desirable are seperate
and distinct things.

Again, with simple logic, modulating a 30 CPS signal with limited voice
freq (say 5K wide) is going to create a LOT of harmonics and mixed
signals, ain't it? Suggesting a very wide band receiver would be needed
to begin with ... in my humble opinion, and for various reasons, NO, it
is NOT possible ...

Regards,
JS


radium, I applaud you in your interest generating discussion.

if there are no questions there are no answers; dumb or smart!

to me your questions came across wonderfully, and generated both
responses.

as humans we stand on two legs, most of us that is.

men get the honor and privilage to stand on three legs from time to
time.

this is our blessing and our curse!

ps. how would u like to change the cell phone industry? and your
discussion group of course!

remeber all things are possible!!!!!!!!!!!!!!!!