[AMRadio] 29080

[Doxemf]

   Our local AM outlet, WNAW 1230 running a KW at ground level just on the edge of downtown North Adams puts out a strong distorted 3rd at 3690 whenever the weather is bad. I don't think they have a local Engineer anymore. It's run remote from Pittsfield I believe.

 Bill, KB3DKS

 

 

-----Original Message-----
From: ne1s <ne1s at securespeed.us>
Subject: Re: [AMRadio] 29080


> I'm not sure I buy into the harmonic hypothesis because the side
> bands are multiplied, too. When that happens the recovered audio will
> be very distorted. Jim reported that he thought the audio sounded
> pretty good, so I doubt that he was hearing harmonics.

It depends if the harmonic generation takes place before or after
modulation. If after modulation, there will be severe distortion.

But, say you have a plate-modulated class C amplifier, and the 2nd
harmonic (for example) is not adequately filtered. The modulator will
happily modulated both the fundamental and 2nd harmonic, and no distortion
will be present on the harmonic. I have heard 2nd harmonics of AMBC
stations sound FB. In this case the harmonic generation is "before
modulation."

73,
-Larry/NE1S

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