I am interested in erecting a Rohn 45 or 55 tower in the 100' - 140' height.
I would like to install my large 10 meter Telrex, 10 element on it, plus a
couple of other smaller antennas above it.
The Telrex has a wind loading of about 12.5 square feet (44' boom). The Rohn
specs call for no more than 12.7 square feet and 15.1 for 90 mph for the Rohn
45 and 55 series, respectively at the 120 foot level. Thus, it would appear
that this Telrex would provide for not much margin of safety in a 90 mph wind
and might be too much for the tower in higher winds. Also, anything smaller,
vhf antennas stacked above the Telrex might cause it to be overloaded for 90
mph winds.
Question - I see, from time to time, many DX stations with several large
antennas distributed up their towers which appear to overload them. I
realize that the limit on the Rohn tower is for a load of that magnitude at
the apex, not over the entire tower. How can I determine what additional
antennas I might install on this type of tower either at the apex or stack
them with some sort of "ring" system lower than the apex?
I welcome all knowledgeable thoughts on this.
Thank you,
Hank Smith
KD4OL
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