What I did was to run a small (1/4" dia) Poly rope the length of the vertical.
Epoxied it at the top, pulled on it to apply tension and epoxied the rope to
the bottom.
73, Dick, W1KSZ
> Date: Tue, 17 Mar 2009 21:59:54 -0700
> From: jimlux@earthlink.net
> To: richard@karlquist.com
> CC: towertalk@contesting.com; K8RI-on-TowerTalk@tm.net
> Subject: Re: [TowerTalk] DX Engineering 66-Foot Vertical?
>
> Richard (Rick) Karlquist wrote:
> >> What I worry about in that case is oscillation under the right wind
> >> conditions.
> >
> >> Roger (K8RI)
> >
> > After much experimenting, I have learned something about the oscillation
> > problem:
> >
> > 1. The worst design is a uniform diameter vertical guyed at equal
> > intervals. This is somewhat obvious from physics.
> >
> > 2. Tapering the diameters is very helpful.
> >
> > 3. For really flimsy verticals, I guy every 15 feet
> >
> > 4. Oscillation may not cause immediate failures, but instead
> > the cumulative effects of fatigue will eventually reach the breaking
> > point.
>
> Particularly with aluminum..(DeHavilland Comets and all that)
>
>
> What about wrapping a rope in a spiral around the outside of the element
> to kill the aeolian vibration (like they use on car antennas these days)?
>
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