John: I was faced with a similar problem in handling the gamma match wire
connection to a horizontal arm on my 131 ft crankup tower. I was concerned
that the flexing of the wire would ultimately cause a break at that point.
My solution was to connect the wire to a small egg insulator. The other end
of the insulator used a short length of dachron rope to the arm. A strip of
flat beryllium copper spring material bridged across the insulator and rope.
providing electrical continuity. I have had no problem with this in 8 years.
I think the same thing would work with Quad antenna wires.
73, Dan, N5AR
----- Original Message -----
From: "John E. Cleeve" <g3jvc@jcleeve.idps.co.uk>
To: <towertalk@contesting.com>
Sent: Sunday, March 01, 2009 5:03 AM
Subject: [TowerTalk] Professional HF curtain arrays
> Good afternoon,
>
>
>
> I wonder, are there any in the group with professional experience of
> erecting the wire curtain arrays, suspended between tall towers, as used
> at
> professional SW BC stations? If there are, then may I ask what method is
> used to connect the feeders to the antenna elements, in order to eliminate
> any "flexing" movement between the two, caused by varying wind pressure,
> which may then lead to metal fatigue and fractures and failure?
>
>
>
> I have trawled through all the information I can find, in books and on the
> internet, but without success. I can only think that the entire wire
> curtain
> array must be suspended under such tension, that it must behave as a rigid
> structure. I would be grateful if any of the group can supply the answer.
> A
> link to an appropriate text book would be much appreciated. 73, John.
> G3JVC
>
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>
>
>
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