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To: neverdem
AT&T adopted direct current for the phone system because of its inherent stability, which is part of the reason that landline phones often survive storms better than the electric grid...

Say what?

Methinks that something got lost in the translation.

8 posted on 11/20/2011 10:27:36 PM PST by Zeppo ("Happy Pony is on - and I'm NOT missing Happy Pony")
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To: Zeppo
>AT&T adopted direct current for the phone system
>because of its inherent stability, which is part of the
>reason that landline phones often survive storms better
>than the electric grid...

Say what?

Methinks that something got lost in the translation.

That part's true. POTS uses +24VDC TIP and -24VDC Ring.

12 posted on 11/20/2011 10:34:23 PM PST by Antonello (Oh my God, don't shoot the banana!)
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To: Zeppo

They use both AC and DC on the same phone lines for different functions. They use DC to register an off-hook condition and to power the carbon transmitters (microphones) and AC to operate the ringers. Later phones use the same DC to power the touch-tone electronic circuitry. It’s about simplicity, not stability.


39 posted on 11/21/2011 3:37:16 AM PST by Fresh Wind ('People have got to know whether or not their President is a crook.' Richard M. Nixon)
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To: Zeppo
Methinks that something got lost in the translation.

Yup....bat'ries.

40 posted on 11/21/2011 3:52:43 AM PST by Roccus (POLITICIAN...............a four letter word spelled with ten letters.)
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To: Zeppo

Telco CO gear does run on 48DC but not for th
e reasons in this story


53 posted on 11/21/2011 5:17:08 AM PST by tophat9000 (American is Barack Oaken)
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