Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.milw.wisc.edu!cs.utexas.edu!uunet!mcvax!ukc!tcdcs!tcdmath!ch
From: ch@maths.tcd.ie (Charles Bryant)
Newsgroups: comp.dcom.modems
Subject: Re: Full duplex / Half Duplex with Telebits
Message-ID: <936@maths.tcd.ie>
Date: 2 Aug 89 18:24:55 GMT
References: <630@lakart.UUCP> <7461@cbmvax.UUCP> <2486@shaffer.UUCP>
Reply-To: ch@maths.tcd.ie (Charles Bryant)
Organization: Maths Dept., Trinity College, Dublin
Lines: 11

In article <2486@shaffer.UUCP> jon@shaffer.UUCP (Jon Doran) writes:
>Now echo cancellation on a V32 connection is not THAT hard.  V32 uses two
>frequencies near the center of the bandwidth, and the echo tends to shift in

Nope. V.32 uses only 1800Hz in both directions. Each end subtracts out its
outgoing signal from what it receives before examining the signal. This can
mean that if one end hangs up, the other end does not notice.
-- 

		Charles Bryant.
Working at Datacode Electronics Ltd. (Modem manufacturers)