[Elecraft] [OT] High SWR on 20 and 40

[djmd]

Hi James,

Thanks so much for the extremely informative reply! I will dig deep into a
lot of your suggestions later tonight. I think I may have overcomplicated
the issue, so let me see if I can give it a shakedown.

First off, lets forget everything besides 40m. That's really the band I am
concerned with first and foremost.

Before Elecraft came into my life, I was using a Yaesu FT840 with an MFJ941E
tuner. Coax (10' or so) out of the tuner, through the floor, into a barrel
that goes through cementboard to the outside. From there, short coax up to a
W2DU 4:1 current balun. Then 16' or so of windowline, and the dipole up
about 20', about 67' long. I have a very restricted yard for antennas and
just wanted to get on the air.

Anyway, after some poking and prodding I was able to consistently tune up on
40m fairly well, 1.5 or less. I made several CW contacts across the country
as well as Canada and South America. 

Then I built the KX1 with the autotuner, and was not able to get under 5:1
from the same point with all the same components in place. No big deal, I
didn't intend on using the KX1 in the 'shack' anyway. But then I built the
K2/KAT2, and was getting pretty much the same result. As it stands right
now, I cannot break below 9.9:1 on the KAT2 on 40m from the shack. I've
tried different coax types and lengths on each side of the barrel and have
seen no improvement. Also, it doesn't matter which balun I use, or whether I
select 1:1 or 4:1 on the BL2. Results are the same.

Now, when I attach the K2 directly to the balun (now an Elecraft BL2) I can
get a great match on 40m. As I can add a very short piece between the K2 and
the balun with no ill effect, but once the coax is longer than about 5', the
SWR shoots up. 

I picked up an analyzer today (259B). It's my first one, and I hardly know
what I'm doing, but I can tell you right off the bat that whether I attach
it to the coax in the shack, or directly to the balun, it's appearing to be
resonant at the same 3 places. Around 10mhz, 20mhz, and 26mhz. If there is
any other information you would like to know from the analyzer at any
specific frequency and connnection point, please let me know.

I hope this helps... I sincerely appreciate everyone's assistance. I'm still
learning and it's nice to have a place to get good info and not made to feel
like I'm an idiot. 
:drunk::confused:




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