----- Original Message -----
From: "Grillo's" <ah3c@frii.com>
To: "Towertalk Reflector" <towertalk@contesting.com>
Cc: "CQ Contest" <cq-contest@contesting.com>
Sent: Tuesday, July 27, 2004 7:46 PM
Subject: [TowerTalk] spider balls
> Since we are on the subject of lightning, has anyone ever used "spider
> balls" to dissipate energy thereby eliminating strikes on the structure?
> These are a steel rod with over 200 fine spiked elements about 2 ft. long
> each that create a cluster of very sharp spikes.
>
> Can you visualize this? I have three spider balls and am considering
> installing one each about 40 feet up from the guy anchors on the steel
guys
> that would be connected to the anchor rods. The balance of the guy lines
up
> to the top of the 120' tower are polyphaser cable, so are insulated. I
> would install three copper ground grids at each guy point and link them
> together with underground copper cable.
>
> The other thought is to mount them on top of the 120' tower and put one
> ground grid under the tower.
>
> I'm looking for alternatives before the concrete gets poured in 2
weeks....
>
> Pete
> W0RTT
>
>
> ----- Original Message -----
> From: "Tom Rauch" <w8ji@contesting.com>
> To: <keith@dutson.net>; "'TowerTalk'" <towertalk@contesting.com>
> Sent: Tuesday, July 27, 2004 2:18 PM
> Subject: Re: [TowerTalk] Lightning Strike - Epilogue
>
>
> > > Analysis of the damage has revealed that the lines running
> > from main house
> > > to shack need to be grounded. But I have decided on a
> > better solution. The
> > > telephone line will be replaced with a new connection that
> > will enter the
> > > shack in a different location that is far from the power
> > entrance. The LAN
> > > connection will be wireless. The TV connection will be
> > removed and a new
> > > dish will be installed for the shack.
> >
> > Keith, I think you are making a mistake. You should bring
> > all lines in at the same point, and bypass and ground them
> > at that point.
> >
> > Moving a telephone line to the opposite end of the building
> > is asking for trouble.
> >
> > Adding a separate small dish is OK, as long as it too enters
> > near the power line and all share a common ground.
> >
> > > BTW, the bolt apparently hit the power lines in front of
> > the house, after
> > > the transformer. The lines enter a weatherhead on another
> > pole and run
> > > through underground conduit to the main breaker panel.
> > The 200 amp main
> > > breaker did not get tripped.
> >
> > Maybe it there, but most likely not. The problems occured
> > because current passed through your equipment on the way to
> > different "grounds". From the extent of the damage when
> > considering the nearly total lack of protection, it doesn't
> > sound at all like a direct hit on your service entrance.
> >
> > Lightning might hit your tower and a large portion of the
> > strike current will flow from the power line, since it is
> > such a massive ground. It may hit a power line, and current
> > flow from your tower ground through your equipment. It may
> > have hit tree down the street, or a mile away.
> >
> > The wireless LAN is good because it totally eliminates a
> > path. The TV feed change at best won't help very much, and
> > if you install a dish away from the power line entrance it
> > can make the problem much worse than simply having a
> > properly installed cable follow the power line to the shack.
> > Moving the telco line away from the power line entrance will
> > certainly make things much worse.
> >
> > The last thing we ever want to do is to isolate devices, and
> > intentionally create multiple grounds and entrance points
> > into a structure or equipment cluster. It is the worse
> > possible thing to do. This is why everyone universally
> > recommends common point grounds and single point entrances.
> > It's why telco and CATV lines enter near the utility
> > entrance and share the same ground.
> >
> > You might consider looking at commercial installations and
> > rethinking your plans. The next hit could be a disaster.
> >
> > 73 Tom
> >
> >
> > _______________________________________________
> >
> > See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
any
> questions and ask for Sherman, W2FLA.
> >
> > _______________________________________________
> > TowerTalk mailing list
> > TowerTalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
> >
>
>
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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