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From: faunt@cisco.com (Doug Faunt N6TQS 415-688-8269)
Newsgroups: comp.dcom.telecom
Subject: AT&T Multi-line Cordless Telephones
Message-ID: <2126@accuvax.nwu.edu>
Date: 13 Dec 89 00:53:32 GMT
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X-Telecom-Digest: Volume 9, Issue 571, message 8 of 11

The electronic phones on an AT&T System 75 can use up to 4 pair.  If
it's a hybrid phone they use one pair for analog, one pair for digital
in, one pair for digital out, and if it's running an accessory, like a
speakerphone another pair for distributing central power.  If you have
no accessories the power pair is unnecessary (this can also be handled
by having a PS local to the device).  If you're using a digital set,
then the analog pair is not necessary.