Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!mcsun!ukc!stc!stl!dww From: dww@stl.stc.co.uk (David Wright) Newsgroups: comp.dcom.fax Subject: Re: Fax Quality Message-ID: <4154@stl.stc.co.uk> Date: 21 Mar 91 18:39:08 GMT References: <3833.27d6468f@hayes.uucp> <1526@integow.uucp> <3842.27da8a2f@hayes.uucp> <427@paralogics.UUCP> Sender: news@stl.stc.co.uk Organization: STC Technology Limited, London Road, Harlow, Essex, UK Lines: 33 In the referenced article shaw@paralogics.UUCP (Guy Shaw) writes: #Am I wrong in these assumptions: # 1) the only reasons that fax modems and computer modems are different are # purely historical FAX modems run at 9600 baud, with downgrade to 4800,2400,1200. (Some cheap ones only manage 4800). V32 modems also run at 9600. But they require much more processing = higher cost. The difference is that a FAX modem only runs 9600 baud in one direction at a time (half-duplex). V32 is full duplex - data in both directions at once. That means you need to do echo cancellation as well as forward equalisation - in other words a LOT more digital signal processing. That's why some FAX modems will support 9600 FAX rate but only 2400 for computer links. Talking of which, does anyone have experience of the SRM-2496 modem, and the Z-FAX software that goes with it? This is a US-made FAX (9600 sync) and V.21,V.22 (600 to 2400 duplex async) modem board for an IBM PC. It's sold in the UK for "#299 list, #169 our price" by Datatech Systems (and no doubt others), and comes complete with the Z-FAX software which allegedly supports FAX send/receive, FAX mail-merge, transmission delay to cheap rate times, FAX to list, print, view with zoom/rotate/clip, and supports PCX and TIF image formats. I'm thinking of buying one. What are the snags? Regards, "None shall be enslaved by poverty, ignorance or conformity" David Wright STL, London Road, Harlow, Essex CM17 9NA, UK dww@stl.stc.co.uk ...uunet!mcsun!ukc!stl!dww PSI%234237100122::DWW