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From: yazz@prodnet.la.locus.com (Bob Yasi)
Newsgroups: comp.dcom.telecom
Subject: Re: CPC / "Wink" Call Termination
Message-ID: <14616@accuvax.nwu.edu>
Date: 12 Nov 90 07:28:26 GMT
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> The service described above (called Cut Off on Disconnect around here)
> is the removal of loop current for a few hundred milliseconds. The
> exact timimgs of this cut off will vary greatly depending on the type
> of equipment installed.

My local central office has a DMS (100 or 200?) switch.  The normal
duration of the disconnect signal (called CPC around here) is 800 ms,
or 0.8 seconds.  This "signal" is the electrical equivalent of
unplugging your phone for the specified duration.  You can actually
see it happening if you have a phone that lights up with led's using
the power supplied by the phone line -- the led's turn off from the
lack of power, then come back on again.

But, some answering machines or other "customer provided" equipment
does better with a longer signal.  If you have the same switch as I do
(and maybe even if you don't) you can call repair and they will set a
software option for your telephone line and up the duration to 1200
ms, or 1.2 seconds.  The service reps seemed to know about this as a
general response to "My answering machine acts funny".

In one of the conversations I had with an actual technical person in
the CO, I asked if there were any other "software options" that were
free.  I was told there were none.


   Bob Yazz -- yazz@locus.com