On Fri, 6 Dec 1996 K7LXC@aol.com wrote:
> My Rohn catalogs go back to 1980 and Rohn 20G isn't listed anywhere. It
> is another TV tower. It's very similar to 25G but lacks the diagonal bracing
> that adds much torsional rigidity to the structure. I would be very cautious
> with this tower since it should be considered to be less (half?) than 25G.
Unless I'm misinformed, Rohn 20 looks just like Rohn 25. It even mates
with 25. I've worked on N8RA's 40-foot tower made of the stuff. The
difference is in the leg tubing thickness--I recall that 20 is #18 and 25
is #16, though I may be off by a tubing size on this. (Steve, I think
you're thinking of the old, flimsy Rohn 6, which has stamped W-shaped
horizontal braces and no diagonal bracing.)
> You're probably overloaded already since the Rohn spec calls for the top set
> of guys to be 5 feet from the top of the tower, not the 25 that you have.
This advice still seems to make good sense!
--73, Rus, NJ2L
nj2l@mdsroc.com
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