Cost can be a factor in how well you can ground a second floor shack
with a lead to earth, from point of view of RF considerations.
Wide flat conductors of copper ribbon would be the least inductive
ground conductor material and desirable. Given the transient nature of
lightning, you can use a conductor that gives you the effective area of
a large diameter wire, but it will radiate the heat of carrying current,
thus can likely survive a high current event, if not too thin.
Wires are inductive, even if straight, and make less desirable earthing
lead material.
One material that has been successfully used was bronze flashing strip,
that was used in older homes to weather strip door frames. It can be
drilled to take bolts and lugs of ground leads to individual radios.
It is sold in rolls that hopefully would be long enough even for an
upper story shack.
Copper roofing flashing used for decorative fireplace finishing, is
another candidate.
Aluminum roof flashing could also be used at the best economy.
Someone mentioned needing 10 feet to get to the outdoor earth rod.
Just remember that anything that is long enough to be quarter wave
resonant will be a potential problem. Thus 8 feet of earthing
conductor would resonate in the ten meter band. 10 feet might be a
problem near 27 MHz.
That becomes the challenge, picking a length that is short, but not
resonant at a frequency you use.
-Stuart Rohre
K5KVH
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