[Elecraft] Using the K3s Tune button causes a growing SWR on my KPA500

[Dave Erickson]

On 7/15/2022 10:21 PM, Peder Kittelson wrote:
> The antenna is homemade, in a sense.  I bought a 9-1 Balun from Balun 
> Designs with the capacity for a tie into a counterpoise which I use.  I 
> have a 30 DB inline RF attenuator attached to the Balun Designs piece.  
> I have run RG213 to my radio room.  I have a separate Palomar 9-1 Un-Un 
> in the line near my equipment.  The EFHW transmission wire is 53 feet 
> long.  A length recommended for multiband EFHW wires.  That length has 
> no natural resonance which would cause problems, according to the charts 
> I have seen.
> 
> Thank you for your thoughts
> 
> Peder
> 
> On Fri, Jul 15, 2022 at 8:07 PM Dave Erickson <radio at disseminator.net 
> <mailto:radio at disseminator.net>> wrote:
> 
>     On 7/15/2022 9:53 PM, Peder Kittelson wrote:
>      > When on 80 meters, the longer I hold the tune button down the
>     higher the
>      > SWR goes to the point the KPA500 folds back with warnings.  I
>     don't usually
>      > hold down the tune button longer than about 5-6 seconds.
>      >
>      > I use a Manual Palstar BT1500A tuner which does a good job of
>     tuning my
>      > EFHW wire antenna.  So the initial tune is very good. I sometimes
>     will hold
>      > down the Tune button on the K3s for maybe 5-6 seconds with the
>     initial tune
>      > at 1-1 SWR.
>      >
>      > The KP500 first shows a 1-1 SWR.  Then 1.2-1, 1.3-1 and so on.  I
>     stop when
>      > it reaches 1.5-1.
>      >
>      > I suppose that initially the transmitting wire sends out the
>     signal and
>      > over time the current backs up.  I have torroids in place to
>     prevent RFI
>      > coming back down the antenna transmission line.
>      >
>      > I only use the system for CW.  So when I send, the problem does not
>      > escalate to the point of a dangerous SWR.
>      >
>      > I wonder if this is a normal problem when holding the tuning button
>      > longer?  And since I do not hold down the key for a long period
>     of time it
>      > doesn't develop.
>      >
>      > Still, I am looking at solutions. And I am concerned.
>      >
>      > Your thoughts?
>      >
> 
>     Hi,
> 
>     Are you feeding an EFHW antenna with balanced feed-line? I don't
>     believe
>     I have seen that done much.
> 
>     Is your antenna commercial or home made? I'd like to see more about
>     that.

Peder,

I am a little confused I guess, but how does this antenna system work 
with the Palstar BT1500A which only has connections for balanced feed-line?

There is a lot going on there I think.

-- 
Dave Erickson
AB0R
73