[geeks] Lightning question

[Francois Dion]

On 7/24/06, Charles Shannon Hendrix <shannon at widomaker.com> wrote:
> Sun, 23 Jul 2006 @ 10:39 -0500, Lionel Peterson said:
>
> > Quick question: We recently had a serious lightning storm not just
> > near by, but actually in our backyard! A tree on our property was
> > struck, and now is spread out across the backyard (oddly, the bark was
> > "blown off",
>
> Not that uncommon.  The tree has a lot of water in it, and depending on
> the exact nature of the hit, it can superheat and cause instant
> expansion, blowing off bark and creating some nasty shrapnel.
>
> > Would it make sense that my 100-150 foot Cat5E cable run from my den
> > to my basement switch would "kill" a switch port?
>
> Wires in electrical and magnetic fields are subject to quite a few
> interesting effects, some of which might generate enough power to fry
> something.
>
> Anyone know what kinds of precautions you can take to help reduce these
> types of effects?

Lightning arrestors:
http://www.hyperlinktech.com/web/hgln_cat5-1.php
http://shop.wirelessguys.com/s.nl/sc.2/category.337/.f
http://www.hyperlinktech.com/web/data_line_lightning_protectors.php


Also, if you have a lightning detector:
http://www.stormwise.com/

You might be able to disconnect your more expensive equipment before
you get a close hit. There's a guy in Eden, NC not too far from me
that has built his own. Looks really cool with a disc detector.

You could also have a VLF listening station, eventually you get good
at detecting storms coming your way. I got some VLF stuff on one of my
websites:
http://www.cimastudios.com/fdion/rocket.html
specifically:
http://www.cimastudios.com/fdion/vlf.html
and http://www.cimastudios.com/fdion/receiver.html

If you are near Huntsville, AL there is such a receiver online:
http://spaceweather.com/glossary/inspire.html

Finally, a great ressource on lightning is:
http://www.k5kj.net/litelink.htm

Francois