[Elecraft] Problem with KAT2?

[Don Wilhelm]

Kevin,

Your logic is flawless as long as everything in the KAT2 is working 
properly.  Yours apparently has some ills.
For instance, if one of the relays is not working, that could leave an 
inductor or capacitor in the circuit at all times, or if you have a bad 
connection somewhere in the KAT2, that would account for your problem.  
I have seen repairs where a BNC jack had its ground pin vaporized 
(perhaps by lightning) - tough to diagnose, but it would not work until 
such things were located.
.
My suggestions are for the beginning steps of checking everything in 
your external setup first.  If the dummy load is not 50 ohms pure 
resistive at the operating frequency, your measurements will be 
misleading.  If the coax has a problem, you end up with incorrect 
conclusions.  Overlook nothing, things of that nature have been problems 
with similar behaviors before.
"Know your tools and know that they are operating properly before using 
them" - quote from one of my college lab professors, and it has not 
failed me yet, but has 'saved my skin' several times.

73,
Don W3FPR

On 7/12/2013 5:41 PM, Kevin Cozens wrote:
> On 13-07-10 10:42 PM, Don Wilhelm wrote:
>> There is one possibility that your 51 ohm load (measured at DC) is not a
>> good 51 ohm pure resistance at the frequency you were measuring.  
>> Borrow an
>> antenna analyzer and test your load at the frequency of operation.
>
> I seem to have thrown people off by including the mention of tuning 
> the KAT2 with a dummy load attached as it is not relevant to the 
> problem. I stated that I set the K2 to calS mode which is supposed to 
> put the KAT2 in to bypass mode according to the manual. The only 
> effect the KAT2 should have on the incoming signal should be minimal 
> based on stray L/C. The 10 fold drop in signal just doesn't seem right 
> to me.
>