[TowerTalk] my long lightning story (was RE: lightning strike)

[Jim Lux]

-----Original Message-----
>From: Charles Gallo <Charlie at TheGallos.com>
>Sent: May 30, 2008 2:22 AM
>To: towertalk <towertalk at contesting.com>
>Subject: Re: [TowerTalk] my long lightning story (was RE: lightning strike)
>
>
>
>On 5/30/2008 Roger (K8RI) wrote:
>
>> According to the NWS literature a strike a mile away can induce voltages
>> as high as a 1000 volts per meter in a piece of wire.


Lots of qualifiers there: "can induce" and "as high as", but, the risk is real, although the vast majority of strikes a mile away won't do anything more than give you a burst of static in your radio.  

I would guess that the vast majority of lightning damage occurs from lightning striking a utility service of some sort (power line, phone, cable tv), and the impulse propagating into a home that way.  No real backup for the statement, by the way, just the impression I get from the literature in general.



>
>One interesting item of note, and this article is making me "think" (a bad thing)
>
>This weekend I got a tour of a USCG Cutter (The Katherine Walker WLM 552), and something I noticed when we walked past the LAN room - they are NOT using 100BaseT LANs, but everything is fibre optics


That's for a lot of reasons.  EMP is one, and just general EMI/EMC issues as well.

>
>I wonder if fibre (which, interestingly is mostly "the past" in LAN design, as gigabit baseT is around) would be the/A future way to deal with our gear.  Think - no ground loop potential, no voltage surge potential etc.  Not cheap, by a long shot, but...

Fiber is wonderful.  Even the inexpensive plastic stuff (used in stereo equipment, for instance) gives you all the benefit.

Copper will have a long life for networks, because the infrastructure already exists.  However, there's an awful lot of fiber being put in for backbone links and such.  




Jim