The 95 per cent rating on a coax, means the shield has 95 per cent
coverage of the coax circumference, and 5 per cent open spaces. I have
never seen any technical article stating that this translates directly
to 95 per cent of the current is contained, as surely that varies with
the frequency being transmitted thru the coax. See the Belden catalog
for further discussions of coaxial shielding.
That is a good project for someone to measure how much current passes
thru the 5 per cent open space. Since the shield wires criss cross in
good woven shields, there may be more shorting of the current, than you
would expect. The shield density affects the bending radius of the
cable and its flexibility. Of course, using less shield wires lowers
the cost of production.
-Stuart Rohre
K5KVH
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