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Gary Schafer
 
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Default SSB Antenna connection

On Sun, 13 Jun 2004 02:26:00 -0000, Larry W4CSC
wrote:

"Jack Painter" wrote in
news:16syc.157$Jk5.41@lakeread02:

outer docks. In the aftermath, we heard there was a lot more damage
from collisions than from lightning, and that is amazing considering
how many yachts I saw get struck that night.

I've read the webpage from FL. Very interesting research. The mast looks
tall when you're standing at the bottom of it looking up, but in the
overall height of a thunderstorm FIVE MILES HIGH, our masts are like a
dimple on the dining room table, and not much of a "target".

I was at the transmitter shack of WRJA-TV, the PBS station in Sumter, SC,
visiting an old friend who was chief engineer, Bill Jones, one night. We
were building the first weather radio repeater after Bill had applied for,
and gotten, an FCC license for that band to simply repeat the signal from
Columbia, SC's weather station to the local Sumter area which had trouble
hearing it. We made it out of kit ham radio repeater boards from VHF
Engineering in Binghamton, NY, as we had a local repeater.

A huge thunderstorm cell moved across Sumter and actually went THROUGH the
1800' WRJA-TV tower while we watched out the back door as lightning went
SIDEWAYS 10 miles in the cloud just to hit that big 1800' ground rod
sticking up out of the table-flat terrain of eastern Sumter County. I'm
standing there watching the light show and suddenly Bill taps me on the
shoulder and hands me a big yellow rain coat, saying, "Come on. I wanna
show you something neat." We followed the huge hardline coaxial cables
from the 35KW TV transmitter out to the base of the antenna and Bill says,
"You're standing in the safest place in Sumter County. There is a cone of
protection against being hit by lightning provided by my tower and you're
now standing in the middle of it. Hang onto the tower leg and feel the
current going through it." I burned my hand a couple of times as the huge
BOOMs went off over my head a thousand feet up. The huge bridge cables
JUMPED from the surge of electrical EMP hit them, many times. The lights
went out and we had to go back in the building to reset the transmitters
when the power came back on.

Though the "tower" on the sailboat is very short, in comparison, I like to
think that if you have a proper grounding system, like the professor
describes on his webpages, you are also in a tiny cone where the blast will
mostly be shunted AROUND you, which is why your car is so safe in a
thunderstorm. The current surge that kills goes AROUND the the steel body
of the car....Steel ships and boats do that....Plastic, not so good.

Larry



Larry, I really don't believe you are that dumb to hold on to a tower
in the middle of a lightning storm. I do see that you are a great
story teller though. However please remember that there are a lot of
folks that read this group that may not be too technically savvy and
may not be able to tell the difference.

Regards
Gary