[Elecraft] KAT-500 behavior under firmware 1.58

[Sam Morgan]

I have had just the opposite results with v 1.58

My amp is an AL-811, I run it at about 300-400w on 160m
My 160m antenna is a 7' tall HiQ screwdriver antenna (also with a top 
hat) @ 20' with 16 radials each 13' long on my apartment roof.

With no tuner my SWR on 160m ranges from 2.0:1 to 4.5:1

With v1.54 I was unable to run the KAT500 in Auto
it would tune just fine and then while talking
it would randomly fold back and start a search
for an elusive low swr point

With v1.58 I am able to find a stable resonant point
yes at first there was a major 'clackity-clack' search,
which resulted in a point 'close' to resonant.

But if I immediately taped the [TUNE] button again,
there is a much quieter, shorter search,
that resulted in a stable tuning point in AUTO.

I can then enjoy my 2 hr morning ragchew with out any retuning.

The next morning when I tune up there may be a brief quiet retune, but 
that is caused by the different overnight moisture changes on the roof.
Once that initial retune takes place it's once again stable.

ymmv

On 2/22/2014 8:10 AM, DeYoung James wrote:
> Greetings, Here is a little "feedback" on the new KAT-500 firmware.
> I installed version 1.58 last night and was using my 160m capacitance
> hat vertical antenna and observed what I think is strange behavior.
> First, I admit my 160m cap. hat vertical is not an optimal antenna.
> Previous versions of the firmware however, produced acceptable
> matches.  Version 1.54 was a little better by introducing the finer
> step search.  The version 1.58 firmware however produces worse
> results in my case.
>
> The tuning passes, the clickity-clack search, is clearly different on
> 160m.  The KAT-500 now finds no good match in auto mode.  I place the
> KAT-500 in "manual" mode and using the utility software set
> previously used capacitance and inductance values.  Now the KAT-500
> goes sometimes into bypass mode (I have no KPA-500), drops setting
> values with an audible click, and some times when I checked the
> utility it has gone far away in capacitance and inductance values
> without a "clickty-clack" tuning cycle.  My K3 used to be able to
> produce nearly full power with its super ALC method of power control.
> According to my Palstar PM2000A power meter, not so much anymore, as
> it behaves now like traditional power fold back on 160m.  It appears
> something is interacting.
>
> I have no evidence of RF in the shack. Jim, N8OQ

-- 
GB & 73
K5OAI
Sam Morgan