I will echo the comment about the SWL case being similar to the ham
station. It is amazing how much current even modest antennas and
feeders can conduct momentarily. If that feeder is robustly grounded,
the surge can be conducted out of the shack to a direct earth ground and
minimize the damage.
With so many chassis these days connected to AC third wire ground, it is
all the more necessary to isolate the feeders from those radios.
Usually the grounding bus and receptacles would be located on an outside
wall to insure straight thru passage of the earth lead in a direct and
without sharp turns manner.
Interior shacks present more difficulty. But, I mentioned having a
disconnect on the outside of the building. That would be a way to
divorce the feeders from any grounding opportunity in the shack that
might carry large currents. Sure, it is a bit more work, but believe
you me, the aggravation of replacing circuit board ground trace that was
vaporized, and fixing blown surge suppressors will convince one to have
a bit of inconvenience in getting on the air, vs. losing equipment to
surges and shorts.
Stuart Rohre
K5KVH
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