TT:
I THINK I answered this, both personally and for posting, but haven't
seen my msg. Vide infra for context, and subsequent comments:
On 1/23/06, Steve Shelton <Steve@bnjcomp.com> wrote:
> Hi, I am fairly new to towers and I have tried to research information
> on rohn's 25, 45 and 55 towers. I have found quite a bit of information
> on these towers but not the exact answers that I am looking. One of my
> questions is what is the maximum safe height on these three towers
> without guying?
IF I recall correctly, 25g is rated for 2 sq. ft. 30' above a house bracket,
or the foundation, if not bracketed. 45g has a higher rating, and 55g yet
higher. I have had 45g with 10 sq. ft, 40' above a house bracket for many
years. Solid.
One would be insane to expect to freestand 25g at any useful height...or to
climb one which appeared to have been installed that way. Remember, aged
towers are weaker than when they went up. Use a crane, if you're taking
down
anything like 50'+. Your life is in the balance.
That said, there are scads of 'commercial' installations with 70-80' of 25g
with one set of guys at the midpoint, and a vhf-gain vertical on top.
They're
simply not safe to climb.
n2ea
jimjarvis@ieee.org
jimjarvis@verizon.net
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