Thanks Gary for the information. Yes, I agree that Roger,
K8RI is a creditable source and in many areas.
However, I am still waiting for an answer to my question to
your statement about knowing that your tower(s) have never
been hit by lightning. How do you know? Do you have a
lightning strike counter?
By what means do you know?
Doug/VA5DX
Subject: Re: [TowerTalk] Lightning Strike
Doug,
You do realize that my comments about the rabbit's foot
protector are in
jest to those that claim that the bleed off type systems are
seen to add
protection to a tower?
My point is that my absurd claim is just as logical as the
claims that
installing bleed off devices prevents strikes. My proof that
it works is the
same.
Many towers can go a life time and not take a hit. Many can
take a hit and
you never know it happened.
Just installing pointy things on the tower and then making
claims that "the
tower hasn't been hit since installed" isn't very scientific
evidence that
the device does anything at all.
That is why I say that I can install a rabbit's foot and
make the same claim
that is just as valid.
If noted, the manufacturers of those "pointy things" all
recommend an
elaborate ground system also be installed.
Would it surprise anyone that installing the elaborate
ground system without
the "pointy things" accomplishes the same thing, less damage
from lightning!
NASSA, the FAA and many others with credibility have done
those tests and
concluded that they offer nothing.
If anyone wants to really know if they take strikes on their
tower
Polyphaser makes a device they call a "lightning strike
counter". It
attaches to the tower with a wire several feet in length
between two points
over a short length of the tower. When a strike occurs there
is a voltage
drop across the tower section due to the high current being
conducted by it
and that voltage is rectified and trips a little counter.
You can tell how
many times the tower gets hit.
They are easily made with a couple of gas tubes and a
veeder-root counter.
As to taking a direct strike and not sustaining any damage,
it happens all
the time on many towers. Even some very large strikes occur
that are safely
conducted to ground provided a good ground system is
installed.
Most strikes are small in reference to the rather rare mega
strikes.
Often the strike will leave small pock marks where it hit.
Sometimes they
are rather large marks.
Roger, K8RI can give you some first hand data on direct
strikes and
surviving with no damage.
73
Gary K4FMX
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