Topband: Skin Effect of RG-6U

[Dennis W0JX]

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.
 
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.
 
73, Dennis W0JX/8