> Force 12s Tapering may have solved low wind speed resonances, However
> I have a broken shortest 10m Director on a C31XR-H which was rated at
> 135mph. That broke at the junction of the 5/8"and 1/2" tube at wind
> speeds of 80-85mph.
Clive is right, I have the same problem. I had a 10 meter director
drop off a ten meter antenna the first joint in from the tip after just
over a year of air time.
I installed rope in the replacement element, but it is too much
headache to repair all the elements with the antenna in the air!
Especially since the blasted rivets prevent feeding a rope into the
element without drilling then out!!!
My Force 12 antennas rattle and hum even in very mild breezes. I
really wish I knew about that problem before I installed them.
End-caps and ropes are cheap insurance.
The antennas going up now (Hygain 5 elements) have both end-
caps and ropes inside the elements. In the future I'll remember to
do that with ALL antennas, no matter what the manufacturer says.
It's a heck of a lot easier to be safe and correct the problem on the
ground BEFORE installing the antenna.
73, Tom W8JI
W8JI@contesting.com
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