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 negatively charged particles looking for a positive ground, as opposites attract. Some lightning strikes contain as much as one billion volts (remember the first Back to the Future movie?). If that awesome charge is strong enough to arc several miles through open air can you imagine how easily it can arc through a rubber or glass insulator. It is amazing how many people believe that the rubber tires of a car keep it from being hit by lightning. There 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 above that lightning is a negatively charge partical arc looking for a *positive* ground to strike. A negatively charged arc is not attracted to a negative 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 ground 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 charges repell not attract. Now with that said there are a few (mostly British) cars from the period following WWII that actually have positive ground electrical systems. Electrically speaking they could attract a negatively charged arc but I doubt it has happened much due to the reason given in a above.
So in short if you merely disconnect the coax from the connector on your house and leave it a few inches or even a few feet away from your house you can seal it in glass, wrap it in rubber or shove it in a ham sandwhich for that matter and lightning can still arc from the cable to your humble abode.
Frank
PS see:
http://www.google.com/imgres?imgurl=http://images.nationalgeographic.com/wpf/media-live/photos/000/002/cache/lightning-over-water_270_600x450.jpg&imgrefurl=http://environment.nationalgeographic.com/environment/natural-disasters/lightning-profile/&h=450&w=600&tbnid=zOwdXoP47bq-8M:&zoom=1&tbnh=160&tbnw=213&usg=__zkPY7nzoAY6ktc1km2namr1l0No=&docid=21jTPmqZw7qgRM
-----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 you 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 of 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 guarantee, but it might keep a lightning strike on the antenna from starting a fire 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 would be best.
Of course, I guess putting in a ground rod would not hurt anything, but I don'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 problems.
But, of course, that doesn't guarantee that I won't have any problems in the 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 station 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 from the ground screw on the TS480 to a terminal ground connection on the back 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 theoretical knowledge in this area is a bit lacking.
Thanks for any thoughts.
Tom Behler: KB8TYJ
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