[Elecraft] Additional experience on KPA/KAT/K3 interoperation issues

[Jack Berry]

I use a SteppIR, DB42 with 60/80 dipole so I expect my case to be different than many others. Regardless, I have been exchanging emails with Elecraft support and thought these two findings might help someone else.


Stumbled on something today that may be at least a partial cause. For a long 
time I had what I assumed was a problem with the power plug to the 
KAT500. I would occasionally hit the power button and got no power. I 
would pull and reinsert the plug or wiggle it and all would be fine for 
days more before it happened again.

This morning I had the KAT500 powered and then in the afternoon it would not power on. I went 
through the routine as before but not dice. I measure 11V at the plug 
and it should have been ~13.8. 
Would under-voltage be a cause of some of these symptoms? Not sure but it's fishy.


I found the fuse on my Rig Runner 12V distribution panel had "almost 
blown". They use automotive fuses.I crawled under the desk and found the 5A fuse position was lit which 
means the fuse is blown. I pulled the fuse and it looks to be still 
connected with a sliver of metal laying diagonally inside the fuse. 
Apparently it was defective all along and we not supply full power for 
some time. Replaced the fuse and all is good. 

I have no way of knowing whether the fuse was deffective or it actually failed in service from over-amperage. Hard imagine the KAT would kill a 5 amp fuse with no other symptoms.
I will find a 1 or 2 amp 
replacement tomorrow as I now realize it should only draw 1 amp max.

Yesterday, before the fuse discovery, I placed a ferrite on the SteppIR control cable just at the cable entrance thinking it might be importing RF from the top of the tower. That seemed to have stopped the issue of higher than normal SWR and retuning and KPA500 "REFL HI" faults. Still early though - we'll see!


I will do a good review of the SteppIR next week I hope. The weatherman 
is saying we should be sunny and 60-70F. Perfect antenna weather.

Hope this helps someone or spurs some creative troubleshooting.

 
God Bless & 73!
Jack - WE5ST
 
God Bless & 73!
Jack - WE5ST