[TowerTalk] Guying Material and resonance

[N7mal]

I have put up a lot of rohn 25 because I have a lot of faith in it. I have 
found the specs on rohn 35 are under rated. Rohn 25 will handle a lot. BUT 
I'm not even 'gutsy' enough to try what you are going to try. I think you're 
fine with weight and 'regular' wind loading. If you get a lot of gusting 
winds you might and probably will be in trouble. You will also be in trouble 
with ice. Your best bet is to move up to Rohn 45.
Just my -2 cents worth.
73


MAL
N7MAL
BULLHEAD CITY, AZ
http://www.n7mal.com
Everyone in the world is
entitled to be burdened
by my opinion


----- Original Message ----- 
From: Jwpjj at aol.com
To: towertalk at contesting.com
Sent: Wednesday, June 11, 2008 18:42
Subject: Re: [TowerTalk] Guying Material and resonance


I am getting ready to install 90' of Rohn 25, base section is all
done,concrete etc and so are the guying stancheons that are set in concrete 
as  well. I
have the first 10' up and hopefully in a few weeks or so will be ready  for
the rest of the installation. My question is what is preferred, steel guying
cable or Phillystran cable. One of my concerns ( maybe it should not be) if 
I
use steel guying installation, should I be concerned about resonance based 
on
the lengths of guying cable. The tower will have a 4 el steppir at approx 
98',
 below that there will be a 3 element 40 meter monobander, prosistel rotator
and  fed with LMR400. Will I need to break up the guys? It seems like it 
would
be a  lot of work if I had too or should I just go for the Phillystran and
don't be  concerned.  This is my first guyed tower as I have always have had
crank  ups. I have seen a lot of pictures that have been on this forum and 
was
wondering what most everyone else uses for guying  their towers. The guying
lengths will be as per Rohn specs, 80% of total height to calculate guys
lengths.

John,  ND1X