[RFI] Noisy transmitters...somewhat long...

Jim Brown jim at audiosystemsgroup.com
Wed Sep 24 00:33:11 EDT 2014

Thanks, Larry.

I'm part of a group that does a county expedition to Tehama Co (near Red 
Bluff, about 200 miles N of SF). We run 3-4 K3s with KPA500 amps. With 
antenna separation on the order of 200-250 ft, we can run two stations 
on the same band.

Yes, the issue for this situation is phase noise, and the phase noise 
plots in my report show it very clearly.

73, Jim K9YC

On Tue,9/23/2014 9:13 PM, Larry Benko wrote:
> Jim (K9YC),
> Very nice job on your report last month.
> I did some work on a multi-transmitter Field Day site a coulple of 
> years ago when I wanted to run 2 transmitters on the same band where 
> W3NQN type filters could not be used to reduce phase noise. It can be 
> found at:
> http://www.w0qe.com/Technical_Topics/phase_noise_and_overload_testing.html 
> and shows how the K3 was the best radio I tested.  By the way we 
> operated 40m CW and 40m RTTY at the same time with NO filters. Ditto 
> also for 20m CW and 20M RTTY with NO interference.  The web page has a 
> link to a PDF of the document if interested.
> 73,
> Larry, W0QE

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