** Reply to message from "Bob" <os2-wireless_users@2rosenthals.com> on Thu, 25
Mar 2010 23:50:10 -0700
> ** Reply to message from "Will Honea" <os2-wireless_users@2rosenthals.com> on
> Thu, 25 Mar 2010 22:27:21 -0600
>
> > Good summary, Mike. We both talked around one fairly critical consideration
> > and that's the telephone system. Every loss I've had here has been to
> > equipment connect to either the phone line or the roof-top antenna. The UPS and
> > a proper grounding scheme is useless if you open a hole in the protection for
> > those two. Mother nature is gonna win if she wants to - the deck is stacked in
> > her favor.
>
> Verizon has installed fiber in my neighborhood so I expect that will reduce my
> exposure to lightning on my phone lines since it only gets converted to wiring
> once the signal is inside the house.
Bob, just don't ignore Mike's excellent info re: emf. Your home almost
certainly contains many linear feet of telephone wiring as pre-wiring became
pretty much standard back in the late 60's - early 70's. The early practice
was to wire 4 twisted pairs (the forerunner of cat 5) in a big loop that
covered most of the exterior walls or at least one wall in each room. That
could easily exceed 150' of wiring, much of it un terminated. Great antennas!
Also understand that the telephone network was - and still is in most places -
floating twisted pairs for a 20 or 40 ma current loop. No ground. The entry
panel has an air gap snubber on each line to ground but the voltage needed to
bridge that air gap still exceeds the input ratings for common electronics.
What this boils down to is that even a near miss can fry anything you are
likely to have sitting on that phone line inside your house (unless you still
use an old rotary dial phone with carbon mics).
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