[Elecraft] K3S QST Article

[Jim Brown]

On Tue,10/18/2016 3:43 AM, Yngvi (TF3Y) wrote:
> How fast does IMD deteriorate with increased power from the K3S or K3?
>
> What are the IMD figures when running 20-25W driving a linear amp. such as
> the KPA500?

I've looked carefully at this, and so has my neighbor Bob Wolbert, K6XX, 
who is an engineer at Elecraft and a serious contester. The first link 
shows my measurements, the second is a pdf of the slides for a talk that 
K6XX gave to NCCC three years ago. It includes measured data showing how 
TX power out and DC voltage affect IMD.  In my measurements, increased 
IMD causes CW bandwidth to increase. You can see that difference by 
comparing measurements at 30W, 50W, and 100W.

http://k9yc.com/P3_Spectrum_Measurements.pdf

http://k9yc.com/K6XXAmpTalk.pdf

73, Jim K9YC