> Coax shields won't take very much current before they melt. A large ground
> wire will lower the impedance between the tower and the common point
> ground, as well as reduce the voltage drop for these low frequency
> components.
RG-8 style coax shields won't take much current before they melt, but as I
mentioned, I have two runs of 1-5/8" heliax running between the tower and
shack, connected to the tower ground system at one end and the SPG at the
other end. For those not familiar with this type of cable, the outer
conductor of each run is nearly 2" in diameter -- basically a big, flexible
copper pipe with a lot of surface area. I don't have a spec on the thickness
of the copper, but it's probably on the order of 1/64". The resistance per
foot is .14 ohm/1000 feet. I don't know the current handling capacity, but
the power rating is 310 KW. Although the heliax is jacketed, and therefore
won't conduct a surge to ground like a bare wire in the trench, it seems to
me that the two large copper tubes present a much more inviting path to the
SPG than the bare wire. True or false?
73, Dick WC1M
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