In a message dated 3/26/2006 6:09:35 A.M. Pacific Standard Time,
> Hi All,
I have been biting my tongue for years about the theoretical load of Rohn
towers. It may be important for building code purposes and surely is for
Rohn's litigation exposure, but in the real world it is really unimportant.
A properly installed and guyed Rohn tower will hold MANY times more than
indicated in the catalogs. I look at the pictures of Rohn 25 with a single
beam at the top because of "loading' and I laugh. Here in the Northeast
there are dozens, if not hundreds of big contesters with super-loaded towers
for years without any mishaps, except for the ocassional 2 inches of ice and
50 mph winds together. My 100 foot Rohn 45 tower has a 15 foot, 3 inch moly
mast with a 4 element homebrew 15 meter beam on a 35 foot boom and a 4
element homebrew 20 meter beam on a 57 foot 3 inch boom. At 80 feet I have
a 2 element Cushcraft 40 meter beam, at 68 feet I have a TH7DXX, at 50 feet
I have a homebrew 6 element 10 meter beam on a 27 foot boom, and 34 feet I
have another TH7DXX, and at 70 feet I have a Ringo Ranger II vertical. You
calculate the wind loading!! It's been up for over 25 years without any
problems. So, If you need official documentation, follow the catalog values.
If you want to put up real antennas, just do it, but do it right, no corner
cutting or compromises in materials. Just my opinion.
Perhaps you should have continued biting your tongue. The aforementioned
anecdotal observations are interesting but have no basis in fact or
engineering practice. Sure, hams overload towers and, sure, most of them stay
that doesn't mean that they are safe and reliable installations.
Ignore the LXC Prime Directive to "DO what the manufacturer says" at
your potential peril.
TOWER TECH -
Professional tower services for amateurs
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