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eHam Forums => Antennas and Towers and more => Topic started by: N2EYE on April 05, 2013, 02:47:58 AM



Title: string tied to antenna to wind sway; Radial wire touching tree.
Post by: N2EYE on April 05, 2013, 02:47:58 AM
Hello Group,
   My antenna is a BTV  with two  65' radials  secured to a fence running  N-S on top of a cliff. The vertical element  on the roof of a  5 story building is about  40 feet away from the cliff.  Roof and cliff are about 68' high.  Strong wind gusts  have bent  my vertical element several times.  On my last antenna re-build  I tied a nylon string from the spider assembly to a chimney to stop wind sway.   Will that affect performance dry/wet.   Also one of my radials goes througha treet-top  and wind pushed branches into the radial wire  will that also affect performance dry/wet?  The radials are two different types of wire--I used something heavier to go over the tree-top.


Title: RE: string tied to antenna to wind sway; Radial wire touching tree.
Post by: WB6BYU on April 05, 2013, 07:59:51 AM
Are you only using your antenna on 80m?  If not, then adding quarter
wave radials for the other bands will help.

I haven't had any issues with synthetic string detuning antennas, though
some of the cotton types may soak up enough water to do so.  I'd
attach it right above the upper trap rather than at the very top of the
antenna, however, as that point will cause less detuning if there is any,
and may help keep the antenna from bowing in the middle.


Title: RE: string tied to antenna to wind sway; Radial wire touching tree.
Post by: N4CR on April 05, 2013, 08:20:58 AM
You can put egg insulators in the guy ropes near the antenna tie off point to keep wet operation normal.


Title: RE: string tied to antenna to wind sway; Radial wire touching tree.
Post by: N6AJR on April 05, 2013, 01:41:01 PM
I use nylon parachute cord, and have for years.  no problem


Title: RE: string tied to antenna to wind sway; Radial wire touching tree.
Post by: N4CR on April 05, 2013, 07:34:30 PM
I'm also using nylon paracord. It's good until it gets UV damage. I change it out every few years.