[Elecraft] Sudden jump in SWR when power above 80 watts

[Rick Prather]

Ken,

Yes, I have the same problem.  

Using a 102' doublet, open wire to a 4:1 outside the shack.  

Works great everywhere above 160M but on 80 the SWR goes nuts over about 75 Watts.  

My workaround has been to not run over 75 Watts  :-)

Rick
K6LE

On 2/18/2012, at 1:40 , Ken <wa8jxm at gmail.com> wrote:

> I am having trouble with my K3 tuner, the SWR jumps high when I turn it above 80 watts on 80m.  
> 
> At first I thought it was something outside but after replacing open wire feedline, balun, coax, I have come to the conclusion that the problem must be internal to the K3.  
> 
> The antenna is a 130' center fed dipole, fed with 45' of open wire to a 4:1 balun and then to the K3.   It tunes easily and works okay on all the bands but on 80m, when I up the power above about 80 watts, the SWR jumps up and the K3 shuts down with "HI SWR.   
> 
> The problem does not happen with my old TS-440, nor does it happen when I bypass the internal K3 tuner and use an external Palstar AT2K tuner.
> 
> I don't believe I had this problem when I bought the K3 last December but then I might not have run the power up all the way either. 
> 
> Thoughts?  Am I missing something?    Has anyone else had this same problem?  
> 
> Another thing I noticed (is it related?) is that when I tune the Palstar to 1:1 SWR, the K3 shows a 2+:1 SWR.  If I use the K3 meter to tune the Palstar tuner, then the Palstar meter indicates a 2:1 SWR.  
> 
> Thanks,
> 
> Ken WA8JXM