Hi Paul,
I have been trying to figure something out here also. I got Away from a
ground mounted vert for the first time in many years recently and 3 days
later we had hurricane force winds for 2 days. For me pointing the
tribander into the wind is best. But, It's not that simple. I have 56 feet
of Rohn 25g with appx 3 feet of the bottom section in concrete. Guyed at
28' with an anti-twist bracket and arms and again at 56' with the guys
dropped over the nose section. I have a Hazer, on a Rohn tower a Hazer does
not go all the way to the top. It needs to sit on a stop and for a Rohn
tower that means it needs to drop down a bit if you use a straight section.
You increase your overall height and have to push your antennas up your mast
less for clearance if you use the pointy section. Guying to the Hazer
increases the weight on it and reduces your payload. I have 12' of mast, a
2m vert, a 40m Cushcraft rotatable dipole and a Telrex TB6EM (6el
tribander). The Telrex is the bottom antenna and it is mounted 25" above
the thrust bearing to clear the top of the tower. The 40m is parallel to
the Telrex. The Telrex weighs 85lbs, with rotor and other antennas, coax, I
am close to 200lb max payload. Because I used the pointy section, it was
easiest to simply make a loop in the upper guys and drop them over the nose.
What I lost and didn't realize it at the time was the ability to decrease
tower twist. With the Hazer it sure looks like I have a lot of twist in the
upper tower. I have much less twist pointing the Telrex into the wind. I
will happily replace elements on my antennas if it means reduced twist on
the tower and rotor.
73
Greg K9ZM
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