Heavy Copper flashing or thicker copper plate is lower inductance to RF
and lightning than wire. Copper Braid can be blown apart by lightning
surges.
A sheet of thick copper is now pretty much out of the question for many
hams due to price increases, but diligent creativity might re-purpose a
brass door pull plate, And certainly aluminum is a good conductor, if
proper anti-oxidation connection technique is used to bond it to other
metals.
There are purpose built commercial entry plates for bringing in feed
lines and grounding before entry into a building and if your operating
desk backs up to a window, these grounding / entry plates could be used.
Wire if used, should be short, and large gauge. Some have used copper
pipe as the common bus behind the desk. You want a short straight path
out of the building to earth from any of these.
And within the shack, avoid double grounding, such as the negative of
the power supply, if tied to chassis at the radio, should NOT be tied
inside the power supply to that chassis, as likely that chassis will
have a 3 wire cord grounding to AC system ground of the building.
And that AC ground outside, SHOULD be bonded to your RF cables entry
panel. Likewise, a tower should have ground rods or crowfoot grounds to
dissipate any charge buildup on the tower from a hit or a nearby hit.
Web pages of Poly Phasor and lightning protection companies have more
detailed information on mitigation methods, depending on how deep your
pockets are.
-Stuart Rohre
K5KVH
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