[Elecraft] K2 problem or is it the antenna?

[Darwin, Keith]

Yep, I've done enough testing (and made enough mistakes) at work to have
caught on to the fact that if something has quit working, look first at
what just changed :-)

In this case I do have some good data that points to the antenna.  The
K2 acts like it is seeing very high SWR which agrees with the Palstar
meter which is measuring a large reflected power.  Only the MFJ analyzer
says 1:1 SWR.  I'm swapping at the connector going into the rig so the
analyzer is looking at the exact system the K2 is which includes the
power meter in the path.  If the power meter said low SWR and the K2 was
acting up, I'd suspect an issue with a connector at the rig end.

Then comes the other piece of evidence.  I've notice recently my manual
tuner settings are not holding from day to day.  The system impedance
just magically changes overnight (wind & precip maybe?)  Also, the
bandwidth of the tuned system has become much narrower.  I used to get
2:1 bandwidth across most of the 40 meter band.  Two nights ago, I
struggled to get 2:1 over 90 KHz.

I'll open the case on the tuner to see if ants or spiders have invaded.

I'll check the connections from the coax to the vertical and from the
radials to the radial plate.

I'll lower the vertical (a bit of a pain) to see if any of the hose
clamps have come loose causing the radiator to sometimes act shorter
than it's actual length.

Gee, while I'm out there, I might as well bury another 15 radials :-)

The biggest bummer is all this takes away from operating time.
Fortunately for me, Ham Radio is about lots more than operating!

73 & thanks for the input Don & Ron!

- Keith -


-----Original Message-----
From: Ron D'Eau Claire [mailto:rondec at easystreet.com] 

By getting consistently good output into a dummy load, it looks like
you've eliminated the K2 as the likely source of the problem.

I'd suggest you check the connector at the rig end. Problems like this
tend to be associated with whatever it is you are changing to make it
appear and disappear, and that seems to be associated with moving that
cable at the rig end between the analyzer and the K2.