[Elecraft] KAT2 SWR readings ?

[Tom Hammond]

Hi Dave:

>I just finished building my KAT2 and was running the calibrations. It
>seems to calibrate OK and agrees with the meter. So far so good. Then I
>set up the SWR. And on 40 meters it was 1:1. Then I went to the higher
>freq. Bands and it started rising on 20 meters it was 1.1:1 but by the
>time I got to 15 Meters it was indicating 1.6:1 and on 10 meters it
>indicates 2.2:1. Anybody got a guess where I should start looking? I'm
>almost sure the SWR indication should not be 2.2:1 on 10 Meters???? Is
>it Normal???

Normal? Well, kinda, but generally not to that extent...

The KAT2 does 'offer' a little stray reactance as you go higher in 
frequency. As a result, this can/will cause indicated SWR to rise as you go 
higher in frequency. But generally the level of indicated SWR does not rise 
to the level you have indicated.

What are you using for your 50 Ohm dummyload? We've found that some 
dummyloads will also 'offer' added reactance as the frequency increases. 
Additionally, in order to do a credible job, you should strive to connect 
your dummyload to the KAT2 through a SHORT (less than 3', and preferably < 
1') coax cable. Direct-connect is even better.

Try using a couple 100 Ohm 2W NON-INDUCTIVE resistors in parallel and wired 
directly into a BNC connector. This should provide a near-50 Ohm load with 
little stray reactance.

Good luck,

Tom Hammond   N0SS