[comp.dcom.modems] Lightning and Ma Bell

RANCK@VTVM1.BITNET ("Wm. L. Ranck") (08/04/87)

   I'm sure someon has responded before this, but here goes.  Voltage
spikes due to lightning can zap a modem attached to you phone line.
I've had it happen to me, and learned that a friend living about
4 houses down the street also lost his modem during the same storm.
These were definitely phone line related.  My modem worked except for
the fact that it was deaf to the phone line.  It responded to
local commands and could even dial, but did not detect voice or carrier
or anything else.  Nothing else was had a problem, only modems were
affected.
   Telephones, at least the old AT&T phones, are *sturdy* and can take a
lot of abuse.  Ever wonder why $10 telephones don't seem to last?  They
can't take a voltage spike, that's why.

Bill Ranck

reh@ccd700.UUCP (reh) (08/12/87)

In article <8708042054.AA02621@ucbvax.Berkeley.EDU>, RANCK@VTVM1.BITNET.UUCP writes:
>    Telephones, at least the old AT&T phones, are *sturdy* and can take a
> lot of abuse.  Ever wonder why $10 telephones don't seem to last?  They
> can't take a voltage spike, that's why.
> Bill Ranck

The old telephones had no integrated circuits or even transistors in them.
The new phones all have integrated circuits and it's easy to arc over a
gap a few microns wide inside the chip.  The lightning arrestor that Bell
put on your phone line (where it comes in the house and connects to the
inside wires, with a groung wire running to a water pipe) will not react
fast enough to save an integrated circuit.
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Bob Harold                      313-845-5404   
Ford Motor Co., DPTC room B-206 ...!ihnp4!mibte!ccd700!eed090!bob
17000 Rotunda Drive             Disclaimer: The views expressed might
Dearborn, MI 48121-6010         not be those of my employer or myself
Have questions about life?  Read the original design manual - the Bible.
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