Hygain supplied rope to put inside all the elements that didn't have traps to
solve the vibrating problem. TH6 and TH7 had mono band elements as directors
and reflectors and it came with the rope. I believe it was Polypropylene. I
don't know if they still do as I don't build too many antennas anymore.
Skip Bolnick, KJ6YCommunications Service Cowww.kj6y.com818-522-5421
In a message dated 8/29/2022 7:42:44 AM Pacific Standard Time,
fishflorida@gmail.com writes:
I had assumed that rope was a passive component to prevent harmonic
oscillations that might be caused with varying winds.
I just found this fine article by PA9X about this exact subject.
Is your antenna making noise? Use a rope! - PA9X
<https://www.pa9x.com/is-your-antenna-making-noise-use-a-rope/>
Mickey Baker, N4MB
Palm Beach Gardens, FL
*“The servant-leader is servant first… It begins with the natural feeling
that one wants to serve, to serve first. Then conscious choice brings one
to aspire to lead." Robert K. Greenleaf*
On Mon, Aug 29, 2022 at 7:25 AM Paul N1BUG <paul@n1bug.com> wrote:
> I'm trying to get a better sense of how the rope in elements to stop
> vibration thing works. I've read that it works because as the element
> swings in one direction, the rope slams against the opposite side,
> providing a counter-force. What confuses me is that I don't understand
> how the rope is free to move around. Nylon or polypropylene seem to be
> recommended but those ropes come coiled or folded and they have a memory
> effect, so they don't lay flat. When put inside an element, they are
> going to be pressing against it in multiple places and directions. It
> seems like that would limit the rope's ability to move to do its job.
> What am I missing? I have seen braided rope with extremely fine strands
> that is soft and doesn't have the memory effect. Is that what I should
> be using?
>
> My 6 meter yagi was having a problem. The element tips were oscillating
> at about a ~200 Hz rate, and the tips were moving at least two inches!
> It took four trips up the tower to rig and get it down. It will take
> another four climbs to put it back up, and more if it still has a
> problem and needs to come down again. I'd like to try to get this right
> on the first try to avoid all that extra climbing. The four foot center
> section of each element is .750" OD, with .625" tips. Any practical tips
> or experiences with similar elements would be appreciated.
>
> Paul N1BUG
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