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[TowerTalk] feeding a Rohn45 rotating tower.

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Subject: [TowerTalk] feeding a Rohn45 rotating tower.
From: (Phil Clements)
Date: Fri, 6 Aug 1999 18:53:49 -0500
Hi Larry,

Been there, done that, got the "T" shirt!
I can empithize with your frustration. If you can, borrow a copy of
new book, "Low Band DX'ing." It will make you very familiar with what
it is
you are attempting to do.

It is very hard to sit out here and visulize what you have. I will
only tell you what
I would do if I was planning the project.

You have too many moving parts, IMHO, to consider shunt feeding. Just
a resonant piece of copperweld from the top set of guys near , the
tower, with
a pully and rope. put in all the ground radials you can, or you can
elevate the
feed point a few feet and use 2 or more elevated radials. If you elect
let me know and I'll try to help furthur, or you can get the same info
from the book.
When you get this playing, you might want to add three more wires and
make a
four-square around the tower.

BTW, the ground rods are impressive and really good engineering on
your part,
but they are of little use for RF purposes, only to take the lightning

Keep us posted on your progress.

Phil, K5PC

>HELP!!  I have a 150ft  Rohn45 rotating tower with only a small 6
>beam and a Cushcraft 40 meter antenna at the top. The lower 40 feet
>fixed and everything above rotates. All guy levels (3) are broken up
>with insuators every 27ft with the set closest to the tower about 5ft
>from each tower leg.  I have been experimenting blindly for at least
>days, trying to determine where the tower resonates and or where the
>ohm point is by using the only means I have available...An borrowed
>MFJ-259 analyzer.  I dont have many radials on the tower at this
>I have 3 fifteen foot 5/8 in copper ground rods at the tower base and
>each is individually connected to its correcsponding tower leg.  The
>ground rods are not all bonded together with a solid #2 wire
>to them yet, but will be..  At the moment I have 5  139 foot radials.
>I have tried a shunt wire at various heights up to 40 feet and
>from the tower up to 4 feet but nothing seems to make any difference.
>have connected to the shunt wire direct and through an 800pf cap..
>Most likely I just don't know what I'm looking for!!
>Any hints rather than "GIVE IT UP".
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