----- Original Message -----
From: "Jim W7RY" <w7ry@centurytel.net>
To: <towertalk@contesting.com>
Sent: Sunday, January 16, 2005 9:28 PM
Subject: Re: NASA and braid was Re: [TowerTalk] There's 'ground', andthen
there's 'ground'
> At Motorola the "R56 Site Standards and Guidelines for Communications
> Sites" strictly prohibits braid of any kind on a communications site.
> Mostly because of the noise it generates when it gets old and
deteriorates.
>
So, not because of the RF (or DC) impedance of braided cable vs stranded or
solid?
> BTW the Motorola R56 is based on the following INDUSTRY STANDARD
DOCUMENTS:
>
> NEC, The National Electric Code.
>
> TIA J-STD-607-A (This is the best document to refer to)
>
> ANSI T1.333 and T1.403
>
> As for NASA, I don't have their document or documents.
>
> When you have fully read the above documents and understand their content
> and proper application techniques........ You will know.....
The NEC doesn't prohibit braid, at least to my recollection (I don't have it
here in front of me). I don't know if the others do. Do they? If they do,
do they provide a reason why?
There are perfectly good reasons to avoid braid (noise, shedding fibers,
etc.), but I haven't been able to find any in NASA documents, which was the
topic of the original post.
_______________________________________________
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.
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