Newsgroups: sci.electronics
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Re: 9600 baud modems
Message-ID: <1988Jul29.194813.27599@utzoo.uucp>
Organization: U of Toronto Zoology
References: <1127@nunki.usc.edu> <478@ns.UUCP> <1044@unccvax.UUCP> <506@ns.UUCP> <1988Jul23.203605.20716@utzoo.uucp> <1047@unccvax.UUCP>
Date: Fri, 29 Jul 88 19:48:13 GMT

In article <1047@unccvax.UUCP> dya@unccvax.UUCP (York David Anthony) writes:
>	Unless and until Telebit Trailblazer, or any other of these
>"tier-two" high speed modems can demonstrate a throughput of
>14,400 bits/sec using random synchronous data, these modems 
>will be rightfully considered to be "second class"...

My recollection is that the link-level bit rate of the Trailblazer on a good
phone line (it adapts much more gracefully to poor ones than the V.xx
modems) is 18k, and the delivered error-free rate is 14k.  This is raw
random-data rate, mind you, WITHOUT DATA COMPRESSION.

>	Having transmitted medical images (essentially random
>data) through every kind of modem known to God, I can with 
>certainty state that the Telebit Trailblazer does not even achive
>achieve 9600 bits/sec on random data.  

You're transmitting with uucp, I assume?  Have you forgotten protocol
overhead?  (For that matter, have you considered the possibility that
the CPU is the bottleneck?)
-- 
MSDOS is not dead, it just     |     Henry Spencer at U of Toronto Zoology
smells that way.               | uunet!mnetor!utzoo!henry henry@zoo.toronto.edu