In a message dated 98-01-18 21:55:18 EST, seay@alaska.net writes:
> The Kellums
> are hoisting grips. They are a great way to pull the transline
> up the tower.
That's right. I never inferred otherwise. I guess I misinterpreted the
original post. With the wieght of a 1 inch hardline, you need the hoisting
grip to haul it up the tower as well as hang the weight from the top of the
tower so that you can install the hangers.
>But - proper dressing requires the cable to be supported
> every few feet.
Quite true. Andrew spec calls for 6 foot maximum hanger spacing for 1
inch cable. That's the same distance I use and recommend for ham cable runs as
well.
> By the way - I've been up a few towers myself and have never seen
> a "Professionally" built installation that doesn't use the hangers.
In my previous posts, I have suggested several methods for attaching the
cable to the tower leg or brace. They should be spaced at the aforementioned
distance.
>
> I would venture a guess that hardline will migrate when suspended
> only a couple of times at 150'. Maybe ham towers that replace the
> equipment every few years would not show the migration, but
> I have to believe over a long period, the weight of the coax on the
> one or two support points would be hard on the cable.
"A couple of times" in 150 feet is just what Andrew specs say for HOISTING
GRIPS (every 100 feet). No one said that the cable isn't attached to the tower
between grips.
> By the way Steve, I don't have the catalog here at home - but
> the coax hanger kits are about 25 Bucks for a package.
> and each package has many in it!
> I'll have to check the catalog tomorrow and get back with you
> with a price. But certainly not 25 bucks each. I use them
> by the hundreds.
Well, not according to the Andrew price sheet. The devices I quoted
previously were in reference to your post:
> They are a small stainless clamp of the proper size with a
> rubber inner boot. The clamp goes around the cable and also
> attaches to the tower with a round member clamp, similar to
> a hose clamp.
A simple round-membered tower standoff kit with clamps, hardware and
hangers for 1 inch cable (p/n 30848-5) is $110.00 for 10 pieces. I don't know
of any ham who will pay those prices when there are other acceptable
techniques.
I'm not trying to pick nits here but wanted to address your concerns.
73, Steve K7LXC
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
Search: http://www.contesting.com/km9p/search
|