[Elecraft] KPA500 Died

[mcduffie at ag0n.net]

On Sat, 18 Jan 2014 19:55:58 -0500, Bill W2BLC wrote:

> I did a similar test using a dummy load (Mil-Spec 2 kW)  with the KAT500 
> in line and carried on a "QSO" while watching all the meters. After 
> about 45 seconds the tuner went nuts and started a retune - with no 
> change in frequency etc. having been made. I did this to eliminate any 
> futher waste of time checking and repairing non-existent antenna problems.

So far, I cannot duplicate this at all.  I know some people are experiencing it,
but I use it regularly on 160M in a part of the band far removed from resonance
of my full wave loop, and it has never retuned.

My KAT scared me one day, much like I would assume the OP was in this case.  The
KPA was in operate but the tuner was interrupting the PTT line, not even a blip
occurred-no attempt to key the amp.  I cycled the KAP through MAN/AUTO/BYP, and
all was good again.  No clue what was going on there.

One thing that confuses me is when I first go to the 160M SSB freq at the top of
the band (antenna resonant bottom of the band).  When I key up and say something
but forget to put out a quick carrier first, the KAT goes nuts.  I would think
that the fast counter (it detects a dit) would at least determine that the RF is
in that band and make the switch.  It won't until I put out a short carrier.

I've strayed from the topic so will sit back and hope the OP will post the
results of diagnostics and eventual cure for the problem.

Gary