PC form factor

From: Dwight Elvey <elvey_at_hal.com>
Date: Thu Jul 8 11:12:43 1999

"Hans Franke" <Hans.Franke_at_mch20.sbs.de> wrote:
> Modemfailure due spikes ? Just out of couriosity - do you still
> have telegraph like overhead single wire telephone connections
> and no protective devices in your area ? (Thats just the only
> way I can imagine to become the modems into #1 failing devices)

 For most things, the surge protectors on phone lines are OK
but if you are within a 1/2 mile or so of a lightning hit on
the phone line, even shielded lines, those small MOVs that
they put on modems are history. Phone lines, and well protected
phone lines at that, are one of the most common sources
of lightning electrocution.
 I once bought a pile of modems that were returns. Almost every
single one had some high current discharge damage. I suspect
that most was lightning caused. In one case, you could see where
it had arced across a 1/8" gap and burned the lead clean of
one of the parts.
 It is foolish to think that any form of protective device,
short of complete isolation will give 100% protection against
a close lightning strike. If you live in an area where lightning
is rare, you may not be aware of the dangers of even using your
telephone. A device with a guarantee against lightning damage,
doesn't mean that it will withstand a strike, only that they
will replace it when it does.
 If you live in one of the areas with a lot of lightning strikes,
and you leave your modem plugged in, you'll surely have your
modem damaged in time. You may even be the damged part if
you are connected.
Received on Thu Jul 08 1999 - 11:12:43 BST

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