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Old July 18th 07, 10:31 PM posted to sci.electronics.basics,rec.radio.shortwave,rec.radio.amateur.antenna,alt.cellular.cingular,alt.internet.wireless
Bob F. Bob F. is offline
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First recorded activity by RadioBanter: Jul 2007
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Default AM electromagnetic waves: 20 KHz modulation frequency on an astronomically-low carrier frequency




How do you determine amplitude?
What's the math (or physics) to derive
amplitude?


The fundamental formular Acos(B) + C is all you need to describe angular
modulation.
Changing the value of A over time determines the amplitude of an AM
modulated carrier.
Changing the value of B over time determines the amplitude of an FM
modulated carrier.
The rate of change of A or B changes the modulation frequency respectively.
C is DC, Y axis offset and has not been discussed here.

r, Bob F.