Andy,
I don't know where you got that long BS from, but you should forward the
following, on my behalf.
== == == == == == == == ==
So much for the polyphasers, differentials and backwards-zaps, etc.
Check out this reprint of an article that appeared in World Radio a few
years ago.
THE SPARKLING & RUMBLING SKIES of SUMMER
(Or, 'Here goes TDF A G A I N')
So, you bought a new rig (radio, transciever = whatever), and
it's
sitting on a wooden table, still in the box. What are the chances
of it becoming part of the lightning PATH, and destroying it?
"None", you say, huh! Well, by gosh you're right. So now you remove
it from the box and admire it sitting on the table. Still no chance
of it becoming part of the PATH, right. Absolutely! Next, after
checking the manual, you hook up an antenna, and plug it into the
AC, (or a power supply that is plugged in). Now your nice new rig
is part of a possible PATH. Whether the PATH be
'CLOUD-ANTENNA=FEED LINE-RADIO-AC-GROUND' (or THE REVERSE),
[I wish not to get into that discussion]. Anyway, - leave it that
way and you are inviting trouble.
For peace of mind you can pull the plug from the AC. If you're in
the basement you can drop the cord/plug onto the cement floor. So,
now you have reduced the potential PATH by having a half inch gap
between the plug prong and the grounded(?) cement floor. Will it
jump
that half inch? DID IT JUMP BETWEEN THE CLOUD AND YOUR ANTENNA?????
OK, so you put the cord up on the table, but in the meantime
you
had put the rotator control box on the wooden table, and it's
plugged
in. How much distance between that control box and the rig? Not near
as far as between the cloud and your antenna, right?
Is there a light, or clock near the rig that is still plugged in? ?
?
But, - wait, - why not just remove the antenna from the rig? Very
good thinking, but that plug better still be pulled, and no GROUND
left attached either! Why! Please study these possible PATHs:-
CLOUD-ANT.-ROTATOR-WIRE-CONTROL BOX-6 INCH GAP-RIG-GND.
CLOUD-AC MAINS-HOUSE WIRING-CLOCK-6" GAP-RIG-GND.
If you are using a metal desk instead of a wooden table then those
6" Gaps become much less, depending on whether there are rubber feet
on the various items mentioned. Of course, if you are not in the
basement then you can pull ALL the plugs and just drop em on the
floor.
As food for thought, (you are thinking, aren't you?), - picture
yourself as an amateur magician. You levitate, (elevate if you
must),
the entire operating position and pass a loop over it, left to right
(and/or vice versa). Did it make it without any wires, or whatever,
interfering?
That GROUND that you insist on having attached to your rig, etc.,
is; - (#1) to keep you from getting electrocuted should there be a
problem with a breakdown between the AC Mains and any part of your
operating hardware that you might touch, and (#2) to improve the
transfer of RF from the rig to the ether. If you want to leave it on
there to enhance that PATH that I have been talking about, then
you're
on your own.
If you take a direct hit from that terrible lightning then there
isn't much to worry about. You will probably lose the TV,
micro-wave,
stereo, telephones, refrigerators, and maybe the whole house.
Remember,
the direct hit may be several blocks away, but, it's those secondary
fingers (like tentacles), from the main bolt that we are to be
concerned with. There may be hundreds of them, so our chances of
gettin hit with one of them is hundreds to one of taking the direct
hit. The only GROUND in my shack is tied to a panel with SO-239 coax
connectors on it. When I pull the power, I transfer the coax cables
from the coax switch to that panel. There is also an AC receptacle
on
that panel, with all pins grounded. It isn't for power, it's for the
rotator control box cord to plug into.
Have I thought of everything? I think so, but, if you come up
with
any suggestions, please don't hesitate. I'm listening! Just because
you have equipment insurance is no reason for you to subject
yourself
to lost operating time while waiting for replacements.
Remember, the important concern is the PATH, and you or your
equipment not being a part of it.
de Ray, (The Grump), W3TDF
w3tdf@juno.com
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