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Old September 29th 04, 06:18 AM
Jack Painter
 
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"m II" wrote
CaveDweller wrote:

Of course, I'm interested in the lowest noise possible, but my main
concern is protecting my new baby.



This is a nice, simple solution. I had to go back in time to find it for
you.


http://www.gutenberg.net/cdproject/c...ah/fig006c.png


mike


NO!

That drawing, taken on it's own, will allow a nearby strike to blow your
radio into pieces so fine you can clean up with a duster. Why? Becasue the
electric power ground (house entrance), and cold water ground (a different
entrance than AC service 99% of the time), and that phony knife-switch
"protector" ground rod, are all at different locations and will have
*enormous* electrical potential between them . Saturated ground from a
lightning strike anywhere nearby will cause races of destructive energy
betweeen all those points, and your radio will be that expensive fuse Mike
mentioned. That is one more drawing of a dozen I have collected of
terrible, mistaken beliefs that isolating "one part" (ie: antenna) can allow
you to make careless errors in other areas. You can't make even one mistake
with lightning! That cold water ground would have to be disconnected, the AC
power disconnected, and that knife switch would have to have isolation over
a FOOT apart to be even remotely safe.

*Or*, if you guys will take the time to read what bonding is all about, all
those systems could have been bonded, a good coax arrestor used instead of
that deadly knife-switch, the coax shield grounded to the rod before it
reached the arrestor, and *then* all you would have to disconnect is the AC
power. Only proper interior surge suppression can allow the safe connection
of AC power to equipment, and that's after all other lightning protection
measures have been taken. So scrap the "here's a simple old idea", and "tie
some granny knots in the cords for good luck" stuff guys. They don't work.

Jack