Frank, you are right!
What was I thinking?
The best thing you can do is make a small unlikely target.
To avoid lightning strikes, move to the Arctic.
-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]]
On Behalf Of Frank Ventura
Sent: Thursday, June 25, 2015 8:26 PM
To: [log in to unmask]
Subject: Lightning strikes, was: RE: Grounding Question
Are you kidding me? Lets think a minute about what lightning is. It is an =
electrical arc, in this case between a cloud and the ground. The arc is neg=
atively charged particles looking for a positive ground, as opposites attra=
ct. Some lightning strikes contain as much as one billion volts (remember t=
he first Back to the Future movie?). If that awesome charge is strong enoug=
h to arc several miles through open air can you imagine how easily it can a=
rc through a rubber or glass insulator. It is amazing how many people belie=
ve that the rubber tires of a car keep it from being hit by lightning. Ther=
e are two basic reasons why cars don't get hit by lightning with the latter=
being more important, they are:
a. Cars are relatively low to the ground and are rarely in a position to be=
the path of least resistance.
b. Almost all cars have negative ground electrical systems. Remember from a=
bove that lightning is a negatively charge partical arc looking for a *posi=
tive* ground to strike. A negatively charged arc is not attracted to a nega=
tive ground. Rubber tires have nothing to do with it. With all that voltage=
if lightning did hit the car body it would arc the gap from the body to gr=
ound below and probably turn the tires into a molten blob of fake rubber in=
the process. It is the negative ground electrical system that makes the ch=
arges repell not attract. Now with that said there are a few (mostly Britis=
h) cars from the period following WWII that actually have positive ground e=
lectrical systems. Electrically speaking they could attract a negatively ch=
arged arc but I doubt it has happened much due to the reason given in a abo=
ve.
So in short if you merely disconnect the coax from the connector on your ho=
use and leave it a few inches or even a few feet away from your house you c=
an seal it in glass, wrap it in rubber or shove it in a ham sandwhich for t=
hat matter and lightning can still arc from the cable to your humble abode.=
=20
Frank
PS see:
http://www.google.com/imgres?imgurl=3Dhttp://images.nationalgeographic.com/=
wpf/media-live/photos/000/002/cache/lightning-over-water_270_600x450.jpg&im=
grefurl=3Dhttp://environment.nationalgeographic.com/environment/natural-dis=
asters/lightning-profile/&h=3D450&w=3D600&tbnid=3DzOwdXoP47bq-8M:&zoom=3D1&=
tbnh=3D160&tbnw=3D213&usg=3D__zkPY7nzoAY6ktc1km2namr1l0No=3D&docid=3D21jTPm=
qZw7qgRM
-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]] =
On Behalf Of Tom Behler
Sent: Thursday, June 25, 2015 8:52 PM
To: [log in to unmask]
Subject: Re: Grounding Question
Jim:
Here's an idea:
To insulate the coax connector, would it be sufficient to put one of those =
rubber boots around the connector, such as those that you get with new runs=
of coax?
I would think that should be a pretty good insulator.
Tom Behler: KB8TYJ
-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]]
On Behalf Of Jim Shaffer
Sent: Thursday, June 25, 2015 6:55 PM
To: [log in to unmask]
Subject: Re: Grounding Question
Tom I never meant to imply that the virtual ground you have would protect y=
ou from lightning. Unplugging the antenna is the best way to go as far as =
I know. In fact, it's almost certainly true that if the antenna, or part o=
f it, is grounded, that would actually increase your chances of a lightning=
strike. You should disconnect the antenna, and perhaps put the end of the=
coax in a glass jar, or some sort of insulator. That's of course no guara=
ntee, but it might keep a lightning strike on the antenna from starting a f=
ire in your trailor.
--
Jim, ke5al
-----Original Message-----
From: Tom Behler
Sent: Thursday, June 25, 2015 11:32 AM
To: [log in to unmask]
Subject: Re: Grounding Question
Well, Jim, this is what I'm confused about, and I sure wish I knew what wou=
ld be best.
Of course, I guess putting in a ground rod would not hurt anything, but I d=
on't think I'm going to be able to do that at least for the next few days.
For the past several years, I have used the system I described, with no pro=
blems.
But, of course, that doesn't guarantee that I won't have any problems in t=
he future should the lightning god strike.
It's just a difficult call, in my opinion.
Tom Behler: KB8TYJ
-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]]
On Behalf Of Jim Shaffer
Sent: Thursday, June 25, 2015 12:01 PM
To: [log in to unmask]
Subject: Re: Grounding Question
Tom, from what I've read, what seems important is to be grounded to what's =
around you. It sounds like what you have now is a virtual ground, which is=
supposedly just fine. I'll bet, if you do put down an 8 foot ground rod, =
you'll see no difference.
--
Jim, ke5al
-----Original Message-----
From: Tom Behler
Sent: Thursday, June 25, 2015 9:01 AM
To: [log in to unmask]
Subject: Grounding Question
Hello, all.
I know I'll get varying opinions on this, but I have a question about stati=
on grounding out at the RV camp site.
As many of you know, my main rig out there is my TS480, and I will be using=
my trusty Alpha Delta DXCC multi-band dipole. When all is said and done, =
I'm hoping the antenna will be up about 30 feet in the trees.
Just as I did in previous years, I will have a ground connection running fr=
om the ground screw on the TS480 to a terminal ground connection on the bac=
k bumper of the RV. I use 10-gauge wire for this connection.
Of course, I am very careful about disconnecting my antenna at any sign of =
thunderstorms.
Is this adequate, or should I be pursuing something additional?
I wouldn't think a dipole would have to be grounded with a ground rod such =
as is the case with a vertical, or a beam antenna on a tower, but my theore=
tical knowledge in this area is a bit lacking.
Thanks for any thoughts.
Tom Behler: KB8TYJ
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