[AMRadio] Physical Reality of Sidebands

Gary Schafer garyschafer at comcast.net
Mon Jan 17 11:01:56 EST 2005

Bob Bruhns wrote:
> Indeed, 'tis a puzzlement.  I can draw three continuous sine waves of
> apppropriate amplitude, frequency and phase, corresponding to carrier, upper
> sideband and lower sideband, and I can add them point by point, and I can
> duplicate a 100% modulated AM signal waveform as we understand it.  I have
> to believe that this works backwards; if I make this waveform by modulating
> a carrier in an AM transmitter, then I am synthesizing the same continuous
> sine waves.  

Hi Bob,

The three sin waves look like what is happening but in reality the am 
signal is not produced by adding sin waves. It is produced by 
multiplying them. It just happens that when you add them you come out 
with the same result so it appears that they are added.
And to keep things simple that is how it has been taught over the years 
as another poster mentioned.

Gary  K4FMX

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