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

[Jim Brown]

On Tue,9/23/2014 8:10 PM, donovanf at starpower.net wrote:
> The cleanest by far is the K3. The dirtiest by far is the FTdx5000.
> The FTdx5000 is so dirty that its essential to install a bandpass
> filter on the output of the transceiver, otherwise strong transmitted
> noise is heard on many other bands. The bandpass filter completely
> cleans up the problem.

Yes, BUT -- as my plots of ARRL data show, the FTDX5000 chews up 4-5 
times more of the band on CW than does a K3, and bandpass filters won't 
help that, nor will they help phase noise on the same band (our CQP 
example, and Field Day). :) Another way of looking at it is that in 
terms of amplitude of the sideband trash, the FTDX5000 is more than four 
orders of magnitude worse than the K3. The surprise (to me) was the 
TS590S, a $1250 radio that was only one order of magnitude worse than 
the K3.

IMO, we all need to be leaning on the mfrs to clean up their act, just 
as Rob Sherwood did for the receivers. And we need to lean on ARRL to 
stop blessing every rig they test. IMO, the Yaesu and ICOM rigs 
shouldn't even be sold!

73, Jim K9YC