On Sun,9/4/2016 10:38 AM, Grant Saviers wrote:
And if losses are resistance driven at HF, how can the loss per 100 ft
at 10MHz be essentially the same for all three and the lowest
resistance cable have the highest loss?
Probably related to skin effect. conductor thickness, and the precise
o.d. of each conductor in each cable. At RF, resistance is related more
to o.d. than to thickness, but at DC, it's all cross sectional area of
each conductor.
Example -- say the center conductors of two cables have the same o.d.,
but the thickness of the tube that forms it is thinner in cable #2. So
cable #2 will have higher DCR, but the two cables will have the same
center conductor resistance at RF. And, of course, the same variables
apply to the shields.
73, Jim K9YC
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