On 3/21/13 1:00 PM, Steve K7AWB wrote:
I have two towers up. A 90 foot Rohn 45 with a 6-el 20 meter beam on it
and
a 102 foot Rohn 25 without anything on it yet. Both are guyed. In putting
them up, a group of us used a Loos tension meter and our eyesight at the
bottom of each tower to make them vertical.
But when I look and align the two towers next to each other by walking
around until they are "next" to
each other, one or both are off vertically with respect to each other.
How do I figure which is straight and which is off or maybe both are
slight off?
I really don't want to climb them now in the bad weather and drop a plumb
bob and do not have a survey level. They are really 135 feet apart.
How far off from vertical are they? You might not care. A foot at 90
feet is less than a degree. The loads won't be appreciably different.
K7NV's website (http://k7nv.com/notebook/towerstudy/towerstudy1.html)
shows displacements of more than a foot on a 100 ft Rohn45 tower in a 90
mi/hr wind. with aramid guys, displacements were more than 4 feet..
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