| I have installed a number of 15 meter beams   and currently  have a 5/5/5 
stack... I learned  many moons ago that especially the 155  antenna  has a  
wind   resonance. on quit days with certain wind speed ( not gusty ) you can 
hear it sing a HIGH note...... Also from the climbed tower the 7/16 " tips   
Hover  like a tuning fork.   resulting in a metal fatigue @ the face of the 
taper joint.... The first one I fixe for a client he thought it just slipped 
out of the  Hy Gain  screw type clamp.  Was a CLEAN brake   But a quick look at 
the manual and parts inventory proved to him   it was about 6 inches SHORT !!!  
 From the total length.
 Any rope will do Polly ,  cotton  cord any  rope to dampen  the vibration. as 
long as it sticks out the total  element length about 4 inches .
I RTV the end and install the cap...
Wayne W3EA
________________________________
From: TowerTalk <towertalk-bounces@contesting.com> on behalf of David Aslin 
G3WGN <david@aslinvc.com>
Sent: Wednesday, June 21, 2017 5:25 PM
To: towertalk
Subject: Re: [TowerTalk] HyGain 155CA dampening rope
Thanks to all for the wisdom, both on and off-reflector.
Clearly the rope should be used with this antenna, as insurance against the 
PITA of taking it down to fix a broken element, if for no other reason.  And I 
learned too that the vibrations that lead to element failure can be just as 
easily caused by a low velocity wind as a high one - so my exposed site is not 
the real reason to use the rope.
I also got some very helpful practical suggestions on end cap installation and 
torque balancing the antenna.
I love this reflector! I'm good to go now with best practice for this antenna.  
Thanks again guys!
73, David G3WGN  M6O
-----Original Message-----
From: Richard Solomon [mailto:dickw1ksz@gmail.com]
Sent: 21 June 2017 20:43
To: towertalk <TowerTalk@contesting.com>
Subject: Re: [TowerTalk] HyGain 155CA dampening rope
Whenever I used Poly Rope in the
elements, I would use Epoxy. First
at the far end, then tension the rope
with a weigh and epoxy the near end.
Never had a failure.
Also, did the same on verticals. Never
needed Guy Ropes on them.
73, Dick, W1KSZ
On Wed, Jun 21, 2017 at 11:08 AM, john@kk9a.com <john@kk9a.com> wrote:
> Hygain uses very thin wall 7/16 diameter element tips attached to a
> much larger swedged tube. In my experience these elements rattle and
> break with no rope so it is probably a good idea to use it. I do not
> like trapping in water with end caps so perhaps you can fasten the rope using 
> a cable tie.
>
> John KK9A
>
>
> To:     "towertalk@contesting.com" <towertalk@contesting.com>
> Subject:        [TowerTalk] HyGain 155CA dampening rope
> From:   David Aslin G3WGN <david@aslinvc.com>
> Date:   Wed, 21 Jun 2017 14:22:22 +0000
>
>
> Mindful of Steve's 'Prime Directive' which suggests I absolutely
> should use the dampening rope in my recently acquired used 155CA, what
> is the experience of the TowerTalkian brains trust of the need for
> the rope in a 155BA/CA at a relatively exposed site?
> 73, David G3WGN  M6O
>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
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