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I had sent in a post regarding lightning protection and some industry
standard practices for proper handling of antenna arrays and masts a week or
so ago. I have expanded that post and put it on my website
www.marinenet.net/antenna%20info.htm that covers SSB antennas from a service
providers perspective not word of mouth on what should work or not... Have a
look and hope it gives you some ideas what has been done, sorted out related
to lightning protection. Unlike Bob, Had a 90 foot tower in the backyard
that the neighbors put up with for some pretty practical reasons... They
were engineers and electricians and loved the fact that they knew my tower
would take most of the hits and their homes had a free lightning rod. Times
when I drove up to the house someone would yell out "Hey John, Your tower
got hit again".
Mind you the tower was LOADED with VHF and SSB antennas and all where
grounded at the top, bottom, room entry grounding plate, Lightning
protectors and finally the radios. Over a 10 year period I lost 1 protector,
no equipment or phone lines. This same setup is used to protect the vast
majority of public safety, TV and radio stations that don't have the luxury
of unplugging equipment so we had no choice but to find solutions to a very
old problem... How to keep lightning out of the equipment. Nope, your not
going to stop lightning if it really wants you however there are a few
important things that are doable no matter if your on a boat or on land to
reduce or minimize damage of a direct or nearby strike.
Boats have a problem of no direct ground contact so attempts to compensate
for this by new fangled swill that promises better water contact than larger
grounding plates... I have faith in real world (large plates) surface area
over small inefficient, easy to install items that give a false sense of
security that it's going to protect against catastrophic lightning strikes.
Out of all the vessels hit I wonder how many were fiberglass vs. metal and
did they provide proper antenna grounding at the mast head, mast base and
entry into the vessel? Did they have lightning plates vs. Dynaplates... Did
their thruhulls blow out due to lightning seeing them as a more direct path
to ground then a Dyanplate and so on... Fact is, you can direct Lightning
strikes to locations where they do as little harm as possible as it had been
done for years but one little speck of metal is not much of a answer. And
only relying on one method either... There are combinations of things that
help.
Is there a sure fire way to stop lightning? No way! Are there things you can
do to keep damage to a minimum? You bet there is! All the best. John WA4FAP
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