After all of my planning and plotting I had decided to go with the Trylon
Titan T600-64 to support my 20 and 40 monobanders separated by about 10' on
a mast. Just for 'one last check' I called a Rohn distributor to see how
much their free standing tower with the same specs as Trylon would cost. To
my great surprise, Rohn does not even make such a tower.
The T600-64 specs (one antenna no more than 2' above the tower) are:
70 mph: 600 lbs, 60 sq. ft.
85 mph: 700 lbs, 35 sq. ft.
100 mph: 400 lbs, 15 sq. ft.
The Rohn distributor said he just flat did not believe the figures - but he
was basing his doubts on the fact that Rohn didn't make one with anything
near those figures.
What is going on here? Is Rohn's strategy to 'never lose a tower' by using
only a ridiculously conservative rating system? Or is Trylon leaving no
safety margin?
Trylon, by the way, used their program on my information about the antennas
and stacking arrangement and came up with an 18% 'reserve capacity' provided
the antenna manufacturers wind load specs were correct.
Is Caveat Emptor (sp) the rule here? If so, how does one make an informed
decision when only the tower manufacturer knows the truth? I guess every
purchase boils down to trusting the mfr by the reputation he has built -
Trylon has this reputation with the commercial microwave towers, but the
Titan ham tower line ???
Just venting.
73,
Frank - W0ECS
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