>From: "Kurt Andress" <NI6W@yagistress.minden.nv.us>
>Date: Mon, 8 Jun 1998 23:19:06 -0700
>Has this been some kinda fun or what? Steve, I guess you got the
>holy wars you were after. HI!
Oohhhh... Yyyeeeeeaaaaaaaahhhhhhh! We're having fun now! ;-)
>Ok, most important things first! It should be obvious why the
>low fat mayonnaise jar is not as effective as the real stuff. It
>doesn't contain enough mass to absorb all of that nasty energy
>and be a good dummy load for the lightning strike. There is just
>no substitute for real mayonnaise. Sheesh!
Obviously. Miracle Whip is no substitute either.
>Now to the fun stuff! We should charter a bus and all go to
>Socorro, NM this summer and play with the lightning researchers.
>This way we could drink lots of beer and test all of our ideas in
>a real life laboratory. The guy with the most successful
>experiments gets to drink for free!
And the guy with the least successful scheme gets to do the
>Then, to the boring stuff!
>There appears to be 4 schools of thought, in this thread, on lightning
>#1) Stay on-line and protect everything properly to prevent
> damage. But, this is too expensive for most of us.
This is not all that black and white. A combination of
techniques can give adequate equipment and personnel protection
without costing megabucks. Especially if continuous operation of
the station isn't a requirement.
>#2) Disconnect everything, everytime it looks like lightning.
Requires far too much diligence and luck for me to seriously
consider this method. Also downright dangerous if not carefully
>#3) Fuzzy looking things are some kind of magic that can make
> lightning strike elsewhere!
No Magic. Sorry.
>#4) Lightning does what it damn well pleases, there is nothing we
> can do but get ready to build a Lightning Ark so we can all
> sail away if it takes control of the planet!
We can very well control what it does as it approaches our high
value targets. If we wish to, we can completely protect a
facility from lightning damage. It is done all the time. There
is little mystery about how to go about it. Only decisions to
make as to whether we care to or not.
>I just have 4 questions:
>#1) Is the cost of proper on-line protection greater than the
> cost of replacement?
That depends. How good is your homeowner's insurance policy?
Will you be replacing any family members?
>#2) Where does all that radiated energy go on the floating
> cables, that are not grounded?
It goes to the same place all radiated energy goes to.
Fortunately, it usually doesn't damage much other than poorly
configured sensitive electronic circuits.
The floating cable is connected to an antenna that is high in the
air (and not otherwise grounded). In this case, the cable may
very well appear to the lightning as a highly conductive path
that makes the apparent distance to earth appear very much
shorter in the cable's direction than the apparent distance in
other directions. Guess what the lightning does then. It jumps
on to this system at the top, and off at the bottom.
Suddenly, we aren't concerned with radiated energy any longer.
What it jumps to at the bottom is the source of all the
"lightning does what it damn well pleases" stories.
Unfortunately, the jump at the bottom involves a very hot (15000
degrees C) plasma released in close proximity to lots of
potentially unfortunate targets. My favorite was a Gas Barbecue
Grill. Pretty spectacular. But the list can include kids,
neighbors, pets, etc. Even the incandescent spray from a near
miss can be pretty disappointing to come in contact with.
>#3) If the bristle brushes work so well for some, why did I see a
> video tape of the Orlando, Fl. airport traffic control tower
> get hammered 3 times in 5 minutes, while it was covered with
> these things? It looked more like a porcupine, than a control
You saw the same thing I have seen. Lightning does indeed strike
these things. A local FM station has a 600ish foot tower out in
the flats. They were having terrible antenna damage every
monsoon season to their side mounted FM antennas and to the feed
on their STL dish. The porcupines appeared to solve their
problem. The antennas stopped getting hit. But the tower didn't
stop getting hit. The lightning simply preferred the porcupines
to the antennas. Until it blew them all off the tower. The
engineer for that station still thinks the porcupines prevent
strikes. So he keeps replacing them. He isn't usually there
during a storm. I don't know why he thinks they keep falling off
the tower. He is convinced that as soon as they fall off,
lightning strikes where they _were_ and leaves a burn mark. Go
>#4) I am an International distributor for tin foil! Why haven't
> you been ordering your Ark sheilding from me?
I found a cheaper source at www.deja_moo.com.
73, Eric N7CL
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