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[TowerTalk] An Engineering Question

To: <>
Subject: [TowerTalk] An Engineering Question
From: (Leikhim, Joe)
Date: Tue, 27 May 1997 23:34:02 -0400
Any chance your new neighbor will give you a long term lease on the 
section of property that you have encroached upon? By the way you may 
have a legal claim on that piece of property in some states due to your 
having taken possession. See if you can work a deal with them and build 
a fence inside their corral to keep the horses from rubbing against the 
guys. Perhaps you can save some expenses.

> David Clemons wrote:
> >
> > Hi,
> >
> >         I have a question concerning guy wire anchor placement.  I have
> > two towers (one is 83 feet of Rohn 25 with a Hygain 155BA and 105BA, the
> > other is 99 feet of Rohn 45 with Cushcraft 204-CD and 402-CD.)  A recent
> > edition of the ARRL handbook says that the anchor distance should be
> > between 60% and 80% of the tower height.  I have two anchors on each leg,
> > with the lower two sets of guys on the inside anchor and the highest guy
> > alone on the outside anchor.
> >
> >         Now the problem - the 13 acres of property behind me was bought
> > last year and the new owners are putting up horse corrals for their
> > boarding/training business.  We recently discovered that four of my guy
> > anchors (both anchors on one leg of each tower) are actually on their
> > property.  They have been nice enough to tell me it's ok, but two of them
> > actually fall inside one of the corrals and I think it best to get them
> > out of there.  I am not going to move the towers, so that means I have to
> > put the anchors closer (the outer ones by 12 feet or so) and also
> > probably shorten the towers somewhat.
> >
> >         The underlying question really is "how much can I cheat on the
> > angle of the guy wires?".  Now there are those among you who will
> > correctly tell me that any cheating is dangerous, and I understand that
> > concept.  However, I am also aware that there is a different amount of
> > danger associated with the anchor at 59% of the tower height than at 39%
> > or 29%.  Also, my use of two anchors takes some strain off the anchor for
> > the top guys - thus making the issue of the strain on the wire and tower
> > legs more likely to be the critical problem.  The guy wire is 1/4 EHS,
> > which I believe is rated for 6600 pounds.  The wires are broken up with
> > insulators, and some of the wires are fastened with deadends while other
> > connections are made using 3 cable clamps on each side.  (If it mattered,
> > I could replace all cable clamps with deadends.)
> >
> >         Does anyone have any experience or idea of the reliability of an
> > installation with the top anchor at 50% of the tower height?  How about
> > as little as 40% (about 68% angle to the ground)?
> >
> > 73, Dave Clemons K1VUT

Joe Leikhim

"tv dinner by the pool, 
i'm so glad i finished school" -F.Zappa 1967

"The Revolution will NOT be televised" -Gil Scott Heron

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