At 11:19 AM 3/13/01 EST, K7LXC@aol.com wrote:
> No - that's the way you do it. Everything inline from the tower to the
>anchor will have the same tension. I covered this in a past "Up The Tower"
>column in CQ Contest magazine.
> Your "perception" about your guys being "considerably tighter" is false.
>If the tension gauge has the same reading, then the tension is the same. Was
>the replacement Phillystran segment EXACTLY the same length? That might
>account for some of the difference. I suspect that what you see is due to
>fact that Phillystran has more elongation than EHS does. 400# tension on a
>guywire is 400# tension no matter where you measure it. I also think that
>your turnbuckles may be contributing to your "perception"; i.e. if it's been
>several years since the original EHS guys were installed, of course the
>turnbuckles may be harder to turn just due to increased friction.
> Bottom line? Measure the guy tension, adjust them to spec and forget it.
I've asked this related question before, and maybe it falls under the
heading of "no matter nohow," but I think it's generally understood that
the pretensioning of guy wires is intended to take them from
"take-out-the-droop" mode to "stretch" mode. Since Phillystran is
significantly lighter than EHS, it should approach a straight line under
less tension than EHS does. For that reason, couldn't it be used with less
pre-tensioning than EHS, giving slightly greater ultimate load capability?
And yes, I know that it is spoecced for the same pre-tensioning as EHS, but
I'm just wondering whether that's correct, or just seat-of-the-pants by
some spec writer...
73, Pete N4ZR
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