Path: utzoo!utgpu!watserv1!watmath!att!linac!pacific.mps.ohio-state.edu!zaphod.mps.ohio-state.edu!julius.cs.uiuc.edu!apple!portal!cup.portal.com!cec
From: cec@cup.portal.com (Cerafin E Castillo)
Newsgroups: comp.dcom.modems
Subject: Re: Telebit Fails under impairments in PC Magazine tests
Message-ID: <36344@cup.portal.com>
Date: 29 Nov 90 21:03:27 GMT
References: <326@comtst.UUCP>
Distribution: na
Organization: The Portal System (TM)
Lines: 37


The TELEBIT T2500 and T1500 modems utilize the Rockwell Chip set to
perform V.32.  While I was with TELEBIT, the quality control problems
experienced with this chipset where quite suprising.

The chipset enable a phone line equalization function which killed
V.32 connections, between Telebits and non-Telebits, within seconds.
This was compensated for in Rev. GE6.01 of the firmware release.
Other such surprises where found, the biggest of which was that the
Rockwell Chipset is only capable of doing 12 kbps as an option and
can never do, in its present form, V.32bis (14.4 kbps).

Telebit has just announced the T1600 modem with its Telebits own DSP
implementation of V.32.  This is the basis for TELEBIT's second generation
of modem products which promise V.32bis and beyond, BUT surprisingly,
this modem is not PEP capable, at present.  The T1600 has a list price 
of $795US.

I would really like to see a magazine review of this new modem versus
the T2500/T1500 modems.

BTW, I assisted the techs conducting these tests, along with a few other
Telebitians.  We found that the test where conducted correctly and the
results where legitimate.  THESE WHERE V.32 TEST ONLY!  PEP was never
tested for inclusion in the review criteria.

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