[AMRadio] Physical Reality of Sidebands

Mark Miller markm at kramrellim.com
Mon Jan 17 08:32:55 EST 2005

At 02:25 PM 1/16/2005, you wrote:
>there is no correct yes or no answer to the age-old question whether or 
>not sidebands are physical reality, or exist only in the mathematics of 
>modulation theory. It all depends on how you physically observe the 
>signal.  Sidebands physically exist only if you use an instrument 
>selective enough to observe them.

The only pure frequency is the sine wave.  ANY amplitude distortion is the 
result of OTHER sine waves in the composite signal.  I think the question 
above arises from the way AM theory has been taught.  The simple, no math 
version which has been taught to technicians primarily takes into 
consideration the envelope as a single entity and is easier for the 
majority of people to understand.


Mark N5RFX

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