Jim: I assume you are talking about a KT34 beam sitting on saw horses in a
horizontal position. Any measurements made in this position are highly
suspect due to coupling to the nearby ground. I have had good luck measuring
yagi swr if the boom is vertical and the reflector is near the ground. I
used a spacing of 12 inches for the reflector above the ground and the
measured swr was very close to what I measured at 40 ft height. The beams
were monobanders for 20 and 15.
GL and 73, Dan, N5AR
----- Original Message -----
From: "Jim White" <jim@coloradosatellite.com>
To: <towertalk@contesting.com>
Sent: Sunday, March 14, 2004 4:20 PM
Subject: [TowerTalk] TK-34 won't tune
> I'd appreciate any thoughts on how to determine the problem with a TK-34.
>
> I purchased a used TK-34 that was just taken down. The boom was in two
> pieces, each element was removed from the boom but not otherwise
disassembled.
>
> I've put it back together on saw horses but the tuning is way off. With
> both driven elements connected the resonance points are way off and none
> are below about 2 X 1.
>
> With the straps connecting the two driven elements removed so only the
> first driven is connected there are nice low SWR points but they are in
the
> wrong places as follows.
>
> 1.1 X 1 at :
> 22.67
> 16.4
> 15.36
> 1.2 X 1 at
> 31.66
>
> All other frequencies are above 3 X 1.
>
> We have checked and tightened all connections and straps.
> None of the cap insulators are broken.
> The 4X1 balun tests shows continuity between the center conductor of the
> coax fitting to one side of the T match, and from the shield to the other
> side of the T match.
> We have measured all dimensions against the manual and they are right on.
> We have looked carefully at all assembly instructions in the manual and
the
> antenna is put together correctly.
> Nothing is bent or has ever been bent.
>
> We are testing with an MFJ antenna meter that we verified good against a
> known good triband beam.
>
> Any thoughts on how to zero in on the problem, what the common problems
> are, what experience others have had, etc. would be appreciated.
>
> Jim
> WD0E
> jim@coloradosatellite.com
>
>
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
>
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>
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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