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Re: [TowerTalk] Lightning

To:, 'Jim Lux' <>
Subject: Re: [TowerTalk] Lightning
From: Doug Renwick <>
Date: Fri, 05 Jan 2007 22:44:11 -0600
List-post: <>
Thanks for the info Jim.  You have a good understanding of
testing procedures.  Do you have the reference study/report
for the testing of the porcupine device as to whether it
reduces or does not reduce the incidence of lightning


Subject: Re: [TowerTalk] Lightning

At 05:30 PM 1/5/2007, Doug Renwick wrote:
>So far nobody, NOBODY, has presented sound empirical data
>that proves the porcupine does or does not reduce the
>incidence of lightning strikes.

Aside from the problems inherent in "proving a negative",
there IS 
published engineering testing that shows no statistically
benefit AND there's a fair amount of theoretical physics
that says 
they provide no benefit.

As the saying goes: "Extraordinary claims require
extraordinary proof"

>  Without that data, you are
>nothing more than an opinion.
>At the bottom read the post from WD4K.

But nowhere does WD4K say anything about spending money on
that has no benefit.  Sure, there's always a cost benefit
tradeoff on 
all lightning protection.  And, contrary to the guy from
statement, you CAN design and build a system that tolerates
strikes.  For instance, the antennas on top of the Empire
building received so many direct hits that they provided a
lot of the 
statistical lightning stroke data used for designining
systems.  The LLL study talks about how to design an
storage area to take worst case lightning or EMP (which is
actually a 
tougher problem).

I've got an open mind.  If a lightning eliminator/static
manufacturer (or anyone else, for that matter) wants to do a

rigorously controlled study and publish the results, I'm
willing to 
change my opinion.  But, if they're going to rely on "we
installed it 
in one place and we didn't get hit (as much) by lightning"
that's not 
real convincing.  And if the mfr is going to play the "as
sold to 
NASA" game to imply an endorsement, that's really lame.  The
is that everybody who has actually gone out and done real
tests with 
decent experimental processes has found no statistically
effect.  This is basic junior high scientific method stuff:
running a 
control group, swapping devices between towers, etc.

And, of course, for lightning protection in general, it's
quite the 
crap shoot, and, in the great middle ground between
nothing and the nuclear trigger explosives vault bombproof
shelter, a 
lot of what you do is "judgement calls". i doubt many hams
would go 
to the trouble to actually do a cost/benefit analysis on all
parts of 
the system, carefully trading off incremental protection
expected loss over time. You do what seems ok and go from
there.  If 
the porcupine makes you think it's safer and you can sleep
better at 
night, it's worth it.

Jim, W6RMK  


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