The Rohn catalogue does indeed specify multiple guy points for their
installations...the ones which are fairly high and ones in which there are
high wind loading.
It is for those reasons, and for one that is quite common here in Florida, (
poor soil cohesion caused by high water table) that I decided to use two set
of anchors.
The first set on my 200 footer takes the guys from 40 and 80 feet on Rohn 55
and is approximately 65 feet out from the bottom. The one further out is
according to the Rohn specs and takes the guys from 120 150 and 190. My
water table varies in depth below the surface but averages 4 feet deep. In
order to do the anchors right, with single anchors, they would have been
sitting in water. During time of the el Nino in 97 and this year's el Nino
they have sat IN water.
Yes, it limits what you put on the lower part of the tower as far as turning
radius, but I sleep a lot better at night with the two sets of anchors. I am
not recommending this for everyone, but if you have high towers, high wind
loading, a location in a high wind area, and crappy soil, it is the way to
go. Certainly, it's no place for screw anchors
Bill K4XS
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