Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!unmvax!polyslo!ddurbin
From: ddurbin@polyslo.CalPoly.EDU (Daniel A. Durbin)
Newsgroups: sci.electronics
Subject: Re: Telephone Signal Modulator/Demodulator Chip
Summary: National Semiconductor TP-5700/5710 Speech Circuit
Keywords: speech, voice, phone, telephone, modulat
Message-ID: <10319@polyslo.CalPoly.EDU>
Date: 14 Apr 89 20:54:20 GMT
References: <17140@cup.portal.com>
Reply-To: ddurbin@polyslo.CalPoly.EDU (Daniel A. Durbin)
Distribution: usa
Organization: Cal Poly State University -- San Luis Obispo
Lines: 32

The Xecom XE1201/1203 MOSART should more than fit your requirements.
The listed features of this device are:
 - small size: 2.25"x 1.0" x 0.5"     -Full Bell 212A & 103 compatible
 - 8251A software compatible          -DTMF or pulse dialing
 - Call Progress monitoring           -DTMF reception and decoding
 - Software controlled audio interface for voice communication or
   acoustic coupling
 - FCC registered                     -Parity generation & checking
 - Synch byte generation/detection    -Extensive inbuilt diagnostics
 - +/- 5VDC power only                -Telephone-line diagnostics
 - Voice synthesis option (1203)      -Synch/asynch operation.
 - Connects directly to phone line

Xecom also has a development kit which includes a board to fit the IBM-PC
slot.  The device was featured as a Circuit Cellar Project in BYTE a couple 
of years ago.

I have built an answering machine plug in card for the IBM PC and will be
marketing them this summer.  I didn't use the above chip however.  I used
a combination of a number of chips.  For the speech circuit (the one that
does the transmit and receive voice modulation), I used the National 
Semiconductor TP-5700 Telephone Speech Circuit which is available from
Aero Electronics as well as numerous other distributors.

I am putting an information package together on my Voice Mail Card and will
be sending it out at the end of the month and I'll include a copy to you.  By
the way, my card was originally a senior project at Cal Poly.

	Daniel Durbin___________________________________________________
	SysOp: Cygnus X-1 BBS		| CIS: 73447,1744
	(805) 541-8505 (data)		| GEnie: D.DURBIN
	EL major at PolySlo		| ddurbin@polyslo.CalPoly.EDU