I've been using fiber for years to isolate my AR Cluster computer (always on
24/7) from the rest of the network. 100 Mbps Ethernet optical transceiver are
readily available and inexpensive (try eBay).
Likewise, surplus fiberoptic cable is readily available and very cheap or free.
Of course, wireless transceivers are another good choice.
73
Frank
W3LPL
---- Original message ----
>Date: Fri, 30 May 2008 05:22:00 -0400
>From: Charles Gallo <Charlie@TheGallos.com>
>Subject: Re: [TowerTalk] my long lightning story (was RE: lightning strike)
>To: towertalk <towertalk@contesting.com>
>
>
>
>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.
>
>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
>
>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...
>
>I mean, we HAVE to switch to USB in the near future, be interesting if we
>could jump to fibre
>
>and RE Serial Ports. Back when I used to work in electronics for a living,
>computers were still VERY expensive items, and I designed a few ISA cards for
>custom work (did you know that IBM sold a tech manual with all the
>voltages/pinouts and timings of all the busses?) Anyway, one of my managers
>insisted that EVERY signal in and out of those cards go through an
>optoisolator. The ones I was using only had a few hundred volt rating, but I
>will tell you - sometimes nasty stuff happened to the units I was connected
>to, and we lost an optoisolator, but we NEVER lost a PC. Guess that's how you
>build things when you are used to building things "Mil Spec" - you should have
>seen some of the specs for "out of tolerance" voltage inputs on some of the
>units we worked on. TTL level input - hit it with 1000 volts, make sure
>things still worked
>--
>73 de KG2V
>
>For the Children - RKBA!
>
>Ox2B | ~0x2B
>
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