Bob, et al,
I'm not sure either. I am about 75 miles from the gulf and the weather is
pretty moderate. Usually not a lot of wind but pretty consistent. We do get
a breeze in the evenings off the gulf but not a wind. All of my antennas
were on the same tower, 90' of Rohn 25. I was pretty irritated when Hygain
told me that they had never heard of this problems before! However, I do
know individuals who have used the highain monobanders with absolutely no
problems, go figure! When I put up my C3 on that tower the problems with the
vibration stopped. Actually, the element tips did not come loose, they broke
off... usually immediately next to where they went into the next piece of
alunimum tubing.
I have moved since and put up 120' of Rohn 25 with a C3E at the top of the
tower and a Hygain 2 ele 40 above. I was real worried about the 40 so I used
the rope, hose clamps, and I riveted each piece of aluminum. I also covered
the hose clamps with Scotch 88. No problems of any kind with either antenna.
Bill, W5VX
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com]On Behalf Of Robet Shohet
Sent: Saturday, August 09, 2003 3:17 PM
To: towertalk@contesting.com
Subject: [TowerTalk] Re: (Tower Talk) Antenna element vibration damping
- How
Interesting Bill. Not sure why you had that experience.
At my qth, I double hoseclamped every place on each element that previously
used one hoseclamp.
I then used a pair of "dykes" to cut off the ends of the hoseclamp and taped
over them with Scotch 88 to prevent them from snagging on guy wires and
other things. I also double nutted every place where there was one nut.
Maybe this would have further reduced any vibration taking place as your
element tips were working loose? Possibly you also have a constant steady
breeze at your qth? I imagine that that could be a big factor as well.
Although I get heavy wind pretty often (especially in the Spring, Fall and
Winter) there are also long periods of calm at my QTH, as opposed to say
Long Island where there is almost always a wind.
I have no doubt that there is still element vibration taking place in my
elements - I just tried to take precautions to reduce it as much as
possible.
73
Bob KQ2M
----- Original Message -----
From: "Bill" <w5vx@hiline.net>
To: "David Robbins K1TTT" <k1ttt@arrl.net>; <va3pl@cuic.ca>;
<towertalk@contesting.com>
Sent: Friday, August 08, 2003 3:24 PM
Subject: RE: [TowerTalk] Antenna element vibration damping - How
> I have noticed that most everyone uses rope in the elements to dampen
> element vibration, but it is not a cureall. I have used this idea as well,
> but have had mixed results. Both my 5 element Hygains (15 and 10) had
> serious element vibration, even with the rope. The tips of the elements
> would vibrate off within a few months. Never had the problem with my old
> TH6DXX.
>
> This isn't just a Hygain problem though, my 6 element KLM 10 meter
> monobander had the same problem. My 6 element 15 was just fine. I have had
> two Force 12 antennas and have not had a problem even without the rope
> trick.
>
> I can still remember the broken element ends on the 5 element Hygain with
> the rope hanging out.
>
> Bill, W5VX
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
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http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
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