NAH! If the tower stayed up it is not overloaded Tree.
The nice thing about the KLM 40M yagis is that they are almost invisible
electrically.
Unless you ground the parasitic elements that is. The boom effect of the
KLM should be minimal. The story would be a lot different if you put a
full "plumbers delight" yagi there.
I had a 4el 40M KLM at 120' at the old QTH and 4el 10/15M Crashcraps
above it. Tuned the tower for 160M and it worked fine. Mother Nature hit
and I had to take the 40M down. Going by ex-W0ZV's suggestions I grounded
the parasitic elements right to the boom. The 40 worked a lot better but
I had to seriously retune the tower Omega Match since all those extra
elements were now part of the hard wired capacity hat.
At your "modest" tower height I doubt if you could do anything but
improve 160M.
The current setup at this QTH for 160-20M is 170' tower with 4/4 KLM's
on 40, 4/4/4/4 on 20M and running various 160M and 80M wires off the
tower. I hang a pair of full size 160M verticals from the top guys and
they tune/work by the book. Interaction on ANY band is not noticed...it
may be there but sure doesnt slow me down.
73...Carl KM1H
On Wed, 23 Jul 1997 10:40:48 -0700 (PDT) Larry Tyree <n6tr@teleport.com>
writes:
>
>Against my better judgement - I am thinking of adding a new antenna
>to the tower I load as a vertical for topband. The tower
>is 72 feet tall - with an 8 foot mast. Mounted at the bottom of the
>mast is a 4 element 20 meter beam on a 36 foot boom, and at the top
>is a 5 element 15 on a 32 foot boom.
>
>The antenna that is being considered is a 2 element 40 (KLM elements)
>on a 20 foot boom. I am looking at putting it up around 55 or 60 feet
>depending on how the guy wire interference works out. This antenna
>will be used for short haul paths on 40 meters (i.e., to W6) during
>domestic contests. It looks good for angles around 30 degrees.
>
>I have heard of at least one case where doing this destroyed the
>magic on topband. I believe my antenna has lots of "magic" currently,
>and am concerned about the impact of adding this antenna.
>
>Does anyone have any experiences that might make me feel better about
>doing this - or bad enough not to attempt it? My only other option
>would be to put it on another tower, in-between a 4 element 15 at 52
>feet and a 3 element 40 at 85 feet.
>
>Maybe I just have too many antennas!
>
>73 Tree N6TR / K7RAT
>tree@contesting.com
>
>--
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>Submissions: topband@contesting.com
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>Problems: owner-topband@contesting.com
>
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