Reader poll:
Those of you with towers larger than 70': What tower are you using?
How much windloading do you have at the top? How much additional side
mount?
AND
Who here has actually calculated the wind loading of their antenans on
guyed towers and determined if they are within the Rohn specified limit?
I would like to correspond with anyone who is familiar with
said calculations, including calculating the allowable loads for side
mounted antennas (yagis). (Please, no hand-waving.)
The way I read it, a simple tribander (TH7DX) (9 sq.ft.) and short
2-el 40 (402CD) (6.4 sq.ft.) are beyond the capabilities of Rohn 45, at
100', 90MPH wind (~13 sq.ft capable). Yes, in the fine print, there is
another 8 sq.ft. allocated for equally spaced side mounts, but is one
to assume that that additional 8 sqft can be placed at the top along
with the 13sqft?
I know there are people with much larger (or similar) loads on a Rohn 25,
which is rated for less load, and does not have the extra 8sqft in fine
print.
How did you deem this safe? Are you playing with fire (or specifically,
wind) or am I missing something here?
I would like to know this so I can determine if this can be overcome by
larger anchors, larger (diameter) guys, strategic guy placement, increased
guying radius, etc.
TIA
---
Chad Kurszewski, WE9V e-mail: Chad_Kurszewski@csg.mot.com
The Official "Sultans of Shwing" Web Site: http://www.QTH.com/sos
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