Don,
For sure, a direct strike will jump a little break like that and head
for whatever it thinks is the path to ground and its opposite charge.
Let's assume that something has happened to the connection because it
was not robust enough to weather, or the direct strike melted solder
and it is now loose and free to corrode. Enough so it takes some
hundred or more volts to jump it.
Now, let's have a strike nearby, which INDUCES voltage on the wires
you intended to protect with the ground. But because the connection
has crapped, and the voltage is a mere hundred or two, it heads up
your coax or rotor wire, or up the down GROUND WIRE out of the shack.
Now you have conductors which are well above zero volts to ground, and
for this small interval of time all your chassis are hot, and the best
path to ground is to jump circuit boards to get to phone wires to look
for some place to dissipate.
Further, for this instant, the green "safety" wire in all the 110
wiring in the house is now several hundred volts looking for a place
to go.
All your electronics have been attacked by ground which has ceased to
be ground. Or worse.
Think it doesn't happen? My son-in-law was pitched clean across his
outbuilding workshop after being shocked by the "grounded" drill press
he was working on. Woke up on the far side of the room.
We later located a faulty ground connection where the out-building's
breaker box was supposed to be grounded.
A lightning strike about a quarter mile away had induced the voltage
on the ground wire in the service feed, and finding no ground at the
outbuilding had proceeded to spread all around the room on everything
that was "grounded".
On a gloomy day, I realize that had the lightning been closer, my
daughter might have been without a husband, and her children without a
father. All by an INDIRECT strike.
The ground system is a multipurpose device. Needs clean clamped or
welded copper-to-copper connections everywhere. Is NOT worth cheating
to save a little time or effort.
73
----- Original Message -----
From: "Mark Beckwith" <swca@swbell.net>
To: <towertalk@contesting.com>
Sent: Wednesday, August 07, 2002 5:24 PM
Subject: Re: [Towertalk] silver solder ok for Ground wire to rod ?
> Uhh, maybe, if its a crappy connection, the lightning might find
another
> path it likes better? Tom, am I learning?
>
> Mark, N5OT
>
> > I don't understand all the fuss about ground wire connections
having to be
> > cadwelded
> > etc. That lightning strike has just traveled hundreds or thousands
of feet
> > through the air to get to that connection. It is not going to be
stopped
> by a
> > few thousands of an inch or a little corrision in the connection.
>
>
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