john@kk9a.com wrote:
> Star guying substantially reduces the twist on a tower. Torque arms are
> much less effective.
I agree on both points.
> According to K7LXC : When Rohn implemented one of the
> early EIA/TIA-222 tower standards, they found that the torque arms added
> nothing to the torque resistance of the tower but they do help stabilize
> the tower as it's being climbed.
>
With this I disagree to a point. Much depends on how the torque arms
are installed, but at best they are no where near as good as star
guying. On my tower I found that following the instructions added
little if any resistance to turning, but mounting the torque arms
*rigidly* made a noticeable difference in the tendency for the top of
the tower to rotate in high winds. However, it's not nearly as
effective as star guying which I'd much prefer. There's an interesting
PP presentation at www.yccc.org/Articles/KE1IH_Dayton.ppt showing
forces on the tower with regular and star guying as well as the force
when using elevated guy anchors.
If possible I'm going to change the top level on mine from torque arms
to star guying. I have a lot of steel and aluminum up there.
73
Roger (K8RI - ARRL Life Member)
www.rogerhalstead.com
N833R (World's oldest Debonair)
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