[TowerTalk] Coax Loss -- RG-Numbers Don't Tell us Much

[Jim Brown]

On Thu, 4 Feb 2010 13:03:06 -0800, Rick Karlquist wrote:

>7977A and 8214 have the same DC resistance but 2:1 RF loss ratio
>8237 and 7809 have the same RF loss but 1.5:1 DC resistance ratio
>(RF loss at 50 MHz).

But Rick, I'm talking about loss at MF and HF, especially low HF 
(that is, 160M-40M), and to a lesser extent, 20-10M. Again, once 
you hit 5 MHz, skin effect becomes increasingly dominant. These 
data are not always published, because most higher priced coax is 
optimized for VHF/UHF, where the differences are more dramatic. But 
if you're buying coax to use on these lower bands, resistance comes 
much closer to telling the story than loss numbers for 50-500 MHz.

73,

Jim K9YC