Also, put your tower/antenna heights in perspective of what the charge cloud
in the sky sees.
Say it's at 5,000 ft. Your tower, at 70 feet, is above everything else
around by about 20 or 30 feet (trees, power lines, street light standards,
etc.).
What percentage of that distance to the cloud is your antenna above the rest
of the ground objects? Darned little.
>From the cloud's perspective, your antenna really doesn't stick out like the
sore thumb you may think it is; in fact, the landscape probably looks pretty
flat to it.
73,
dale, kg5u
> -----Original Message-----
> From: towertalk-admin@contesting.com
> [mailto:towertalk-admin@contesting.com]On Behalf Of Jon Ogden
> Sent: Thursday, December 12, 2002 00:03
> To: n4kg@juno.com; TOWERTALK@contesting.com
> Subject: Re: [Towertalk] Lighting Protection and Roof Towers
>
>
> on 12/12/02 12:05 AM, n4kg@juno.com at n4kg@juno.com wrote:
>
> > So much for hitting the tallest objects around...
> >
> > (Thank Goodness ! )
> >
> > Any ideas why?
>
> Yeah, it's all about where the potential can build up. Like I
> said, if you
> can make your antenna/tower look as much like ground as possible
> and prevent
> any charge from building up on it, you are less likely to take a strike.
>
> Lightning is going to occur at the point where it is easiest for
> the charge
> cloud in the sky and the charge cloud at some ground point can most easily
> break down or ionize the air between them. Keeping your antennas at earth
> ground or as close as possible will minimize that chance. So even though,
> you were a "higher" object visibly, you were not electrically.
>
> This may not be a 100% correct technical explanation, but it
> certainly gets
> most of the way there.
>
> One purpose of a lightning system is not just to be able to take hits, but
> to be able to avoid getting hit all together. To not get hit is
> the safest
> protection.
>
>
> 73,
>
> Jon
> NA9D
>
>
> -------------------------------------
> Jon Ogden
> NA9D (ex: KE9NA)
>
> Citizen of the People's Democratic Republik of Illinois
>
> Life Member: ARRL, NRA
> Member: AMSAT, DXCC
>
> http://www.qsl.net/na9d
>
> "A life lived in fear is a life half lived."
>
>
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