NASA and braid was Re: [TowerTalk] There's 'ground', andthen there's 'ground'

[Jim Lux]

----- Original Message -----
From: "Jim W7RY" <w7ry at centurytel.net>
To: <towertalk at 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.