I can't speak for anyone else, but when I was very active my equipment
was never disconnected. The big problem at that time was it took too
much time to disconnect things. If you heard thunder from an
approaching storm, there was not enough time to safely disconnect one
station safely, let alone both. However, during that period, the big
tower with the TH-5 tribander @v100', 7L 6-meter C3i 29'6" boom @ 115',
a stacked pair of12L 144 C3i and a stacked pair of 11L 440 C3i on a
cross boom @ ~130' took 17 visually verified direct strikes with no
damage. It did take a hit before the ground system was finished that
IIRC cost a new computer (less than a week old, state of the art), the
front end of a 2-meter rig, and a bunch of 9913 coax full of water after
all the water proofing was blown off. But no damage after the ground
system was in.
HOWEVER: a few weeks ago, a nearby strike (I don't know the direction or
how close, but it was loud!) took out my network, router, 8 port switch
and the Gigabit NIC on one computer. The OS and programs had to be
reinstalled as well. With the NIC, OS and software changes, I installed
a new motherboard. I'll troubleshoot the old one...some day.
The Gigabit CAT 5 network is getting replaced with dual band wireless as
that wired network runs between computers in the shop and house which
are on two different electrical feeds/services. With dual band they are
getting reasonably fast, (not fast enough) but having to troubleshoot
and completely reinstall the software on one of these monsters is far
too much work even with a system image and repair disk. Those are worth
their weight in gold. I've had one go flaky recently and those disks
reduced the repair time to a few hours.
73
Roger (K8RI)
On 10/25/2014 7:13 PM, Bill Turner wrote:
------------ ORIGINAL MESSAGE ------------(may be snipped)
On Sat, 25 Oct 2014 13:37:19 -0700, David wrote:
Lightning may not care about a half ohm resistance, but anything else
that might care about the volt drop across a half ohm at currents
typical in a lightning discharge sure as hell would.
REPLY:
Pray tell, what else do you have connected to the hot side of the
ground rod? When lightning is near I disconnect everything.
And what about the resistance of the earth itself? Even if your ground
rod connection is perfect, the earth itself has resistance and if you
are foolish enough to provide a path between your lightning ground rod
and some other ground, current will flow between them.
73, Bill W6WRT
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73
Roger (K8RI)
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