Path: utzoo!utgpu!watserv1!maytag!xenitec!zswamp!izot
From: izot@zswamp.fidonet.org (Geoffrey Welsh)
Newsgroups: comp.dcom.modems
Subject: US Robotics HST compatibles (Re: modem)
Message-ID: <1196.26FBE9BC@zswamp.fidonet.org>
Date: Sat, 22 Sep 90 14:23:09 EDT
Organization: Izot's Swamp BBS - Kitchener, Ontario

 > From: laird@slum.MV.COM (Laird Heal)
 > Message-ID: <1990Sep21.143505.1490@slum.MV.COM>
 
 > The 'real-world' numbers I have seen with streaming protocols
 > on my 14.4kbps HST-DS in the HST mode, namely 16.6kbps for .Z
 > files (that is not a misprint; maybe the modems drop start/stop
 > bits) and faster-but-I-never-reliably-measured for text, seems
 > a little faster than the real-world transfer rate of Telebits.
 
   MNP3 does indeed strip start and stop bits. Under ZMODEM with data 
compression turned off, an HST 14.4 should be able to do in the vicinity of 
1750 CPS - it is wisest to diable data compression when transferring only 
compressed files.
 
   The limit to how well files can be compressed is the speed at which the 
data is being sent to the HST. My 9600 HST transferred text at up to 1825 CPS 
but, since I'd only expect about 1825 CPS from ZMODEM at 19,200 bps, I am sure 
it could have gone much faster. It would be intesting to send a megabyte of 
nulls through a 14.4 HST at 38,400 bps and see what the throughput rate is. I 
suspect it'll be near 3600 CPS.
 
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