All,
Jim brings up an important distinction, a low RF IMPEDANCE, not just wire
resistance.
The lowest impedance will be a wider than thick, conductor. Ideal would be
copper strap.
Many sources say, "well braid is wide and flat in larger sizes, thus it should
do." Remember skin effect. The lightning has a fast rise transient, (high
frequencies content) pulse, and will tend to explode the pieces of woven braid
if a direct hit is made on such a ground. Then any follow on strokes will have
no ground connection. Solid conductors rather than stranded are usually
written into electrical codes for grounding conductors. Note the solid
conductor used on a telephone/power wood pole. If you are in a high lightning
stroke per year area, use the best means of grounding your station, and still
provide a disconnect point for all cables from the rigs, preferably on the
outside wall of the shack.
Flashing copper for roof work, should be available widely from construction
and builders supplies or lumber yards. This, in the heavier gauge, will give
the best strap, or there are some copper straps used in the plumbing trade.
Watch out for only copper plated strap, which is not as effective.
73, Stuart K5KVH
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