[Elecraft] K3S QST Article

[Wes Stewart]

What method(s) did you use to verify the accuracy of your dB(c) numbers?  I get 
a little queasy when I see "-48.5 dBc."

On 10/18/2016 10:51 AM, Jim Brown wrote:
> 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