>From Andy's note:
Which makes me wonder if we will ever really understand lightning.
- - -
This reminded me that years ago on a lot adjacent to ours, a neighbouring
apartment building with a TV tower mounted on the roof and an overall height
maybe 20' higher than my Ham tower took a direct hit. In short, the tower
was blown off the roof of the apartment building onto the parked cars, the
main electrical feed to the building was vaporized as well as any surface
wire around the building. There was a hole that went right from the roof to
the basement about a foot in diameter. Most of the shingles on the roof were
curled and a lot of aluminum trim around the roof was badly damaged. I sort
of recall only the electronics in the basement apartments were damaged.
Thankfully no persons were injured.
At our place, nothing damaged in the house, including all my station which
was not disconnected at the time. We only had the phone line surge protector
pop.
Like Andy said, will we ever understand lightning hits.
Eric - VE3GSI
-----Original Message-----
From: Andy
Sent: June-20-10 3:07 PM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] Is lightning hitting the tower..or the yagi's
There are still people (companies too) who support the theory that
lightning strikes can be prevented by installing suitable devices to
dissipate the charge before it can build up. I believe it is still
hotly debated between camps, but from what I've read, most data seems
to say that the notion of dissipating charge and preventing strikes,
is just plain bogus.
I've also read that some states in the USA have laws making pointed
lightning rods illegal (but round balls are OK), on the assumption
that they increase the chances of your house being hit and burning
down.
There are a lot of bad theories and questionable "data" out there.
And there probably always will be, as long as there are people who can
profit from them.
There's some sort of lightning theory I've seen mentioned by experts
in the last few years ... sorry, I don't know what it's called ...
about imagining a huge ball touching the ground, as tall as your
buildings and towers; and if you rolled it around, anywhere the ball
can touch, could be hit by lightning. The purpose of this is to
describe areas underneath and around tall objects, that are supposed
to be protected by the taller object. It's not cone-shaped (as was
previously thought), it's described by this ball thingy.
But I still read about cases where objects directly lower, still do
get hit (take the picture of the Shuttle on the pad for example, if it
wasn't an illusion); so I'm thinking even this new theory may be
wrong.
Which makes me wonder if we will ever really understand lightning.
Andy
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