For towers of moderate height, 35' to 45', I have successfully
supported Rohn 45 and 55 towers with quite large 2m EME arrays (8 or
more 28 ' long yagis and their supporting structures) by using struts
not guy wires.
I use 24' lengths of the top rail material used on chain link
fences. It's about 1 7/8" in OD. I weld up saddle type mounts out
of 2 x 1/8" flat steel plate/strips ( available in 3' to 4' lengths
at larger HW stores) single holes are drilled in the saddles'
vertical sides to bolt the top an bottom the 34' rail and the bottom
ends of the strip is drilled to accept the proper size U bolt for the
towers leg. The saddles for the bottom of the rail, the bottom strip
is drilled to accept about 5/8" x 1' to 11/2' J bolts on each end
that will be imbedded in a cube of concrete, about 1' x1' x
11/2', these are placed out from the bottom leg of the tower about 6
or more feet away. These each provide bracing, "guying", in both
compression and tension. Water pipe could also be used and lengths
coupled together for a longer length, but would be much heavier.
Standing on the top of the tower with and without these "braces"
proves the rigidity that they provide, even on a Rohn 55.
Chuck, W7CS
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