[Elecraft] KPA1500 Using Multiple Antennas With the Tuner

[K8TE]

I too have the same issue.  I worked with Dick on this, but there is no
solution currently available when using an external antenna switch
(necessary with more than two antennas) with the KPA1500.  Unfortunately,
there is no way for the KPA1500 to tell the K3/K3S to use a different drive
level, even when using ANT1 and ANT2 on the same band, but with two
different antennas that require different tuning solutions.  

My (not yet implemented) initial solution is to use a macro for band changes
that will drop the drive level based on previously-determined data when
selecting a new band/antenna.  The long term solutions is a computer (Pi,
Arduino, PC, etc.) with the appropriate tables with the data entered from
empirical testing.  I only wish the ability (firmware and hardware) had been
included in the original design.

I'll take my KPA1500 to Lubbock next weekend for the CQ WW DX SSB Contest. 
I reconfigure the station's antenna switching to use ANT1 and ANT2 in the
KPA1500.  I carefully choose antennas by band so the two ports use the same
antennas by band and train the KPA1500 tuner appropriately.  The KPA1500 and
2x8 antenna switch follow the IC-7610 band and frequency data.  The hardest
part is prying the KPA1500 out of the station owner's hands so I can take it
back home!

Anyone with near perfect antenna systems (minimal tuning solutions needed)
won't have this problem.  Maybe I'll get there someday?  As Rosana
Rosanadana used to say:  "It's always something."  (not the same without
Gilda Radner voicing it!)

73, Bill, K8TE

P.S.  I have also noticed a big (300-400 Watts) difference in output after a
"long" pause in use (15-30 minutes) along with the difference between
antenna solutions on the two ports for the same frequency.



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