[Elecraft] K3 - NOT K3S - issue: TX Calibration fails on 6m only

[Jim Spears]

I am helping a friend upgrade an older K3/100 (s/n 798) after he recently
acquired it from estate of a SK.  I have brought firmware forward one or two
versions and installed the KIO3B board set.  The radio has main RX only and
the KSYN3A upgrade.  It does have the KANT3 antenna tuner.

 

I ran the 5 watt TX Calibration and it failed due to high swr on 6m only.  I
thought this curious so ran this test against one of my K3S with the same
high quality dummy load and cable.  It passed.  I also scanned the dummy
load with my RigExpert and it is flat to at least 2m.

 

We would appreciate any suggestions as to how to further troubleshoot this
issue.  My friend says that 6m is not important to him - today - but
tomorrow might be a different story.  It seems reasonable to us that so long
as we are working on it, we should leave it fully operational.

 

I have not looked to see if the front panel to main board pin upgrade or any
other hardware mod has been performed.  

 

Jim

N1NK