[Elecraft] K3 Power Issues

[Don Wilhelm]

Mark,

I don't think it is anything to worry about.  That is only a 4% 
variation which is quite small in such things in amateur equipment.

The power control loop is controlled digitally.  I don't know how many 
bits are involved in the calculation, but I would bet the DAC steps are 
2 or 3 watts on the high power range.

For example:
If the calculation one time comes out to equal 50.0003, and that value 
is fed to a DAC whose resolution is equal to a 2 watt increment, the 
actual power developed could be anywhere between 50 and 52 watts - it is 
all in the math which can be quite exact, but the hardware DAC cannot 
handle those small decimal values, so the calculation is truncated by 
the hardware.

73,
Don W3FPR

On 11/22/2013 4:35 PM, pastormg2 at verizon.net wrote:
> Hi, it's Mark Griffin, KB3Z. Perhaps I should have described my problem a little better. I am currently on 20 meters and I hit the Tune Button and the screen is showing 50 watts. But sometimes it jumps to 52 watts and maybe that's because the SWR changes on occasion from 1.6 to 1.5. I checked the Tune Setting in the Config Menu and it reads normal. This just doesn't seem right to me. Perhaps I have an issue with my K3. Any help would be greatly appreciated. Mark Griffin, KB3Z
>