In a message dated 2/15/2009 4:55:28 P.M. Pacific Standard Time,
towertalk-request@contesting.com writes:
> just got a KT34A up on my tower.? I had tested it on the ground, sitting
on top of a couple sawhorses, and SWR seemed fine?on all 3 bands according
to my mfj antenna analyzer.? Got it up on the tower and I can't get even the
slightest dip in SWR from 7mhz to 40mhz... let alone on 14.025, 21.050 and
28.050 where I expect?it!? I've looked at connections and all looks well
except
I'm a little suspicious of the connection between the matching section and
the driven element.? The aluminum strap which tightens around the matching
section and driven element seems loose.? This is a new/used antenna so I'm not
sure if that was the case when it was new.?
?
> I've put a different coax on it to make sure the coax isn't the problem.?
Checked the antenna analyzer on another antenna and all seems well there.?
Tried continuity testing between the coax and different elements and
basically, there was continuity everywhere... coax braid to both elements,
etc.... I
suppose I was seeing that?because the balun was still in line?
?
> My best idea is to take the balun off the antenna and then do some more
continuity testing.? I'm also wondering if the old balun (15 years) didn't
make it through the trip from the ground to the tower.?
High swr everywhere is typically a feedline problem. Take your analyzer and
connect it directly to the feedpoint. If the antenna looks okay there (that
is, it dips somewhere and looks like an antenna), then start working your way
back. From your description, the balun sounds suspicious. The only way to
test one without a bunch of test equipment is to substitute another one.
> Of course, the next step after that will be to take the antenna back off
the tower... ugh!!!
It's too late now but if you were to use a tram system for antenna
installation it would allow you to run the antenna up and down easily to check
and
possibly retune your antenna off the ground before installing it. I can send
you
a chapter on this technique from my upcoming tower book if you're
interested.
Cheers,
Steve K7LXC
TOWER TECH
**************Need a job? Find an employment agency near you.
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