Richard, my earlier posts described the grounding my friend, here is quick
summary:
1.Well grounded 100' tower, hundreds of feet of many radials, rods, etc.
Survived many strikes.
2. Feedline from tower's dipole was disconnected about 20' from tower where
it enters a buried pvc conduit that travels 150' to house, then up to second
story shack. Where nothing is grounded, except by virtue of house AC
wiring - a bad I know (not mine either).
3. Ground current from the tower strike most likely entered the coax
feedlines at the disconnect point as they entered the pvc conduit then
traveled on into house.
4. House current also took huge jolts, zorching all kinds of connected
equipment, phones, tv's etc.
5. Outbuilding with radio equipment connected took huge hit, ball lightning
inside room fried test cords connected to nothing, hanging on test bench,
where the leads touched tile floor, huge blow-out of tile. AC power blew
wall warts across room, computers next to each other had .22 rifle bullet
sized hole between them. Equipment in this bldg was grounded, and some that
was was damaged, others not touched. In short, a massive, multiple
strike-path hit that may not be protectable from - but I realize there was a
lot missing from a good ground picture here also.
Jack
"Richard Clark" wrote
Ask yourself "Where is ground in this picture?"
THAT is the Common of the Common Mode. I see it discussed nowhere in
your description. There is the inference of it being back in the
house (code requires it) where lightning eventually found it, the hard
way.
As you describe it:
The coax in question was disconnected about 150' from the house,
disconnected where, how? Up the tower? At the bottom of the tower?
Is the tower grounded? Does the tower ground meet code in being tied
to the house ground? Is the coax grounded? Where? Does it supply
ground? Where?
The Drake was the luckiest of the second-story ungrounded shack gear.
No ground? There are two problems with this statement.
1.) It is unlikely due to code;
2.) It means you accept Common Mode problems.
It being unlikely does not mean you are protected (experience proves
this), it means you went with the flow - of several KV.
73's
Richard Clark, KB7QHC
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