[TowerTalk] Re: kt34-A tuning

[Jeff Singer]

Rod - 

I am a bit perplexed about all the "tuning" that occured on or near the
ground. The time to tune an antenna is AFTER you build it to EXACT mfr
spec, mount it where it belongs, then find out it doesn't work well.
Some will no doubt disagree.

I have a rebuilt kt-34a also, strapped to my tower at 55 feet. IMO, the
tower has absolutely no effect on it. SWR is NOT perfect everywhere, but
it is perfectly usable everywhere on EVERY band. It was made from the
remains of my old kt34-XA, and is not in great shape. It still has some
spider nests in some of the slightly mishapen tubes, and lives 19 feet
below a large 4-el 40-mtr KLM monobander, BUT it was built to exact mfr
specs. My 'XA survives at 90' and is flat just abt everywhere. 

With that in mind, and ALL bands being resonant at freqs LOWER than the
design specifies, it would seem that the antenna needs to be
"re-measured" and shortened. I know you won't want to hear this, but if
it were me, I'd go to the reflector and start there. Bruce might suggest
something a bit different, and if so, I'd definitely go with him. He is
my KLM guru.

There is something else you might try - and I will probably get blasted
for this (because I usually do), but - you might try adding several
different lengths of coax to your feedline to see if that will make any
appreciable difference in your readings.

Also, I wonder if there are any other extenuating circumstances, such as
a large 40-meter array close by.

Good luck. I am definitely NOT an expert, just a KLM owner and true fan,
so please only add my advice to the sifter before you decide your
direction.

73 de Jeff K2KV
k2kv@netusa.net
--------------------------
>... not over 1.3:1 over the full 350 KHz
> but the 1.0:1 dip was at 13.850.  15 was truly rotten: not under 2.1:1
> over the entire 450 KHz with a minima (1.7:1) at 20.910 MHz.  10 appears
> to be a little better; starting off with a 1.1:1 at 28.000 and progressing
> to 1.5:1 at 29.300 but with a dip to 1.0:1 at 27.700 MHz.
> 
> I am at my wits end.  I spent a full week working on the antenna and
> tuning it at parallel 3 feet off the ground, parallel 6 feet off the
> ground, pointing up at a 45 degree angle, etc.  It looked good just two
> days ago before I disassembled the elements from the boom and started,
> piece by piece, to install it at the 70 foot level.
> 
> Rod, N5HV, ex W5HVV
>

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