[TowerTalk] BLACKENED BRAID?

K0DAN k0dan at comcast.net
Tue Jun 14 10:56:37 PDT 2011


Thanks for your input Steve...this is good info, and could be the issue 
here, as the severed coax was above ground level (barely), however most of 
the run is underground and I expect the same deterioration. Whatever the 
cause, I think this whole run is gonna get pulled up and replaced. Replaced 
with WHAT is still up for grabs.

Tnx es 73

Dan
K0DAN


----- Original Message ----- 
From: <K7LXC at aol.com>
To: <towertalk at contesting.com>
Sent: Tuesday, June 14, 2011 10:55 AM
Subject: Re: [TowerTalk] BLACKENED BRAID?


> Here's what it says in the Coax chapter (page  140) in my UP THE TOWER 
> book
> (_www.championradio.com_ (http://www.championradio.com) ).
>
>>  Another advantage of RG-213/U is that the jacket is made
> from  non-contaminating PVC unlike regular RG-8/U. Any cable used
> outdoors is  subject to years of sunlight abuse. The UV radiation
> from sunlight causes a  chemical reaction with the standard PVC jacket
> material and the chloride from  the jacket material (polyvinyl chloride,
> remember?) starts to migrate, or  leach, toward the inner dielectric
> and through the copper braid. Not only  does the braid get all gummed
> up, but also it degrades the performance of the  coax and it only gets
> worse over time. In an extreme case, the chloride will  coat each
> strand of braid and actually insulate each strand from the  others.
> You’ll have continuity on each strand but not from one to the  other.
> The SWR of the coax (not the antenna) will rise over time due to  this
> feedline degradation and you’ll have to replace it. If you are in  the
> Sunbelt or are at a higher than average elevation, the  non-contaminating
> jacket is probably mandatory.
>
>    So your problem is either this or water incursion.
>
> Cheers,
> Steve     K7LXC
> Champion Radio Products
> Cell 206-890-4188
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk at contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
> 



More information about the TowerTalk mailing list