I have a question re the copper grounding strap: When visiting a small
local 250 w. AM broadcast tx site last year, I noticed the base of the tower
insulator on the ground side was strapped to the radial ring with 4 sections
of what appeared to be aluminum flashing. The insulator sat on a square
concrete base and the straps, one on each side, came down off the insulator
base where the spark gap was to the buried radials. Each Al strip was about
4" wide. I was surprised to see a metal other than copper being used. (For
no reason that makes any sense, I expected to see the whole concrete base
covered with copper--my ham tendency to want to over-engineer everything.)
I may have been mistaken but I don't know what else it could have been--if
it looks like aluminum, walks and quacks like it, it's aluminum. Is Al
flashing an acceptable substitute for copper? It's easier to find and
cheaper. I imagine it presents bonding oxidation problems however.
Rob Atkinson
K5UJ
k5uj@hotmail.com
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