Finally got finished with my tower project today: 80 ft of 45G with a 20 ft
3/8" wall CrMo mast and 10M, 15M, 20M KLM monobanders on top. I guyed the
tower per the Rohn catalog. This puts the top guy down several feet from the
top of the tower. Found out after the fact that this configuration is
intended for commercial installations more than heavily loaded ham
installations. When you get to the top with the load I have, it's pretty
obvious why. A good twist on those long booms can torque the tower. But it
sure made it nice putting up the beams.
My question is this... rather than move the guys and brackets up to the top
of the section (where it would make it difficult to haul up and take down
yagis because it's in the way) should I add a "third" guy of Phillystran on
the ears of the top flat section? The other guys are EHS, and I've heard
arguments against adding extra EHS guys. Is that strictly because of the
weight of the EHS or the downward force any additional guy tension may have
on the tower? With this "extra" set of guys, I could drop them when
adding/removing antennas while keeping the two sets of EHS in place. I
really don't think it would be a good idea to move the current top set of
guys without some sort of temporary guying... particularly with all that
stuff up there. And if I'm going to install temporary guying I may as well
put up the permanent stuff. Will cost another $400 or so, but that's small
change compared to what I'm trying to protect.
If this idea is not so far fetched would you use the 4000# or the 6700#
Phillystran given the top EHS guy is only a few feet below the top of the
tower.
Larry WI5A
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