On 1/31/2011 3:02 PM, Dennis W0JX wrote:
> I have found that the quality, and therefore the loss, of RG-6 cable varies
> quite a bit. On the average, I measure about 14 ohms of resistance in 500
> feet if shorted at the far end. Recently, I put up a dual flag RX antenna and
> felt that the sensitivity was far down from normal. It turned out that my
> resistance was about 20 ohms for 500 feet. I discovered some oxidized
> connections in a splice and also some water contaminated aluminum shielding.
> If you are going to use long runs of RG-6, I recommend Quad with the larger
> center conductor, very careful sealing of any splices to prevent moisture,
> and if available, flooded cable to seal any pinholes.
Great advice. Also, stick to major mfrs like Belden and Commscope.
>
> I have found that the low-price Home Depot stuff has a PVC jacket which is
> easily cut and exposes the braid to moisture. The aluminum shield then starts
> oxidizing.
See http://audiosystemsgroup.com/Coax-Stubs.pdf
73, Jim K9YC
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