If everything is perfect in the world with your grounding systems how
fast is fast enough to prevent damage from a direct lightning strike of over
100,000 A at a freq near 10 Gigs. The heat that can produced from a
strike is that greater then the temperature of the Sun.
A little over 10 years I lived in Kempton, PA atop a ridge at 1000 ft ASL.
My tower was grounded OO wire from each leg about 6 ft up from the base.
We had an indirect strike of lightning come through our 400A underground
service, fuse the line and destroy all electrical and electronic devices
plugged into the outlets. Cost over $30,000 w/o the electrical service.
The above ground transformer box was completely destroyed and the concrete
pad gone. that service was for about 6 homes
I guess this is why I can't believe you can protect yourself from a direct
In the 60's I worked for a radio station WAEB. I remember what we went
through grounds and megging the system. I was told the important thing was
to keep the strike outside the transmitter/studio building.
I can't disagree with most of the steps that are taken, It takes a lot of
copper in the ground, taking reading with a megger, and trying to stay away
from the RF ground system. However, I think they will only prevent
transients, not direct strikes
de Skip K3CC
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