I have a run of inch & 1/4 hard line up my 80' tower. When got it up
and clamped down at the top, was very surprised to see how much it
whipped around in the wind. I wound up clamping it to the tower every
three feet or so.
It is grounded to the tower at the top, and grounded to the tower at
the bottom. And is buried 220 feet to the back of the house. Where it
goes through lightning suppression.
The lightning susceptibility of stuff coming down one of the guys just
boggles the mind. It will be the PREFERRED PATH, to avoid what you
have done at the base of the tower. Lightning that wants to go toward
your house will get there first down that guy-fastened wire. So it
will have the LEAST back-EMF built up at any given point.
73
----- Original Message -----
From: "james Colville" <w7ry@earthlink.net>
To: <george.shaw@ukf.net>; <towertalk@contesting.com>
Sent: Thursday, January 10, 2002 12:48 AM
Subject: Re: [TowerTalk] Low Loss Coax
Andrew has a specification on how much of a vertical run you can
support. Please use the Andrew hoisting grips.
As I remember 1/2 inch LDF should be supported every 100 feet.
You can support the vertical cable run with a "messenger" cable to
take all of the stress of the cable hanging vertical.
I would contact Andrew directly and ask them (or Times if your are
going to use LMR type)...
And remember Heliax is a trademark of Andrew. (NOT ANDREWS! as no many
want to call it.)
Good luck on your project!
Jim W7RY
-----Original Message-----
From: K7LXC@aol.com
To: <towertalk@contesting.com>
Date: Wed, 9 Jan 2002 10:33:58 EST
To: george.shaw@ukf.net, towertalk@contesting.com
Subject: Re: [TowerTalk] Low Loss Coax
>
> In a message dated 1/9/02 5:47:42 AM Pacific Standard Time,
> george.shaw@ukf.net writes:
>
> > What is the minimum static bending radius on coax. Very few give
that
> > detail.
>
> It's typically six times the diameter so the minimum bending
radius for
> 1/2" coax would be three inches. I probably wouldn't stress
foam-filled coax
> that much due to the potential for foam cold-flow problems.
>
> > And how do you deal with an installation of say LM-600 that has
to
> > go horizontally then vertically (from the 12th floor apartment to
the roof
> @
> > 15th floor)? Is it OK to fit a 90 degree connector?
>
> Sure. But if you can put something under it to protect it from
the sharp
> edge as it crosses the edge of the roof, then you don't really need
the 90
> degree connector.
>
> > What sort of loss would there be? I have hear mention of 1.5db
per
> connector?
>
> It's not that much. Andrew, the Heliax people, use 0.2 dB per
connector
> in their loss calcs. According to some guys on TT it's even less
than that.
>
> Cheers,
> Steve K7LXC
> Tower Tech
>
>
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>
--
Jim W7RY
______________________________________________________________________
__
This list is sponsored by the new eHam.net Store. When you buy
products
like ICE filters, Array Solutions StackMatch, or M-Squared Antennas
from
the eHam Store for the same price you pay direct, a portion of the
sale
price goes to support this list. Check it out at http://www.eham.net.
-----
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Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
________________________________________________________________________
This list is sponsored by the new eHam.net Store. When you buy products
like ICE filters, Array Solutions StackMatch, or M-Squared Antennas from
the eHam Store for the same price you pay direct, a portion of the sale
price goes to support this list. Check it out at http://www.eham.net.
-----
FAQ on WWW: http://www.contesting.com/FAQ/towertalk
Submissions: towertalk@contesting.com
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Problems: owner-towertalk@contesting.com
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