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Re: [TowerTalk] Coax

Subject: Re: [TowerTalk] Coax
From: Jim Brown <>
Date: Sun, 08 Apr 2012 22:59:24 -0700
List-post: <">>
On 4/8/2012 9:12 PM, K8RI wrote:
> I don't know if the big coax makes much difference on 75 but the
> resistive loss is much less on 160 compared to the RG-8 size cables.

I'm certainly not advocating against coax that is truly lower loss -- 
the runs to all of my Al antennas are either hard line or heliax, and 
I'm using low loss RG11 to feed high wire dipoles for 80 and 40.  
Rather, I'm simply observing that Davis's 213 is half the cost of 
LMR400, with essentially equivalent performance on the HF bands.  If I'm 
paying twice as much for coax, I want to get my money's worth. :)

As to the life of coax -- I don't have your decades of experience with 
LMR400, but I did have occasion to re-cycle hundreds of feet of 20 year 
old RG8-size coax of various pedigree from the estate of a silent key. 
Most of it was Times or Belden, and most of it had been outside for most 
of those decades. I couldn't give it away, so I made stubs out of it and 
measured their response. The attenuation of a stub is directly related 
to its conductance at the frequency of the null, and virtually all of 
that old cable that hadn't gotten wet inside measured as good as new. He 
also had some low grade stuff, and I threw that away.  I also bought all 
of his heliax and a huge spool of 1/2-in CATV hard line.

73, Jim K9YC

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