[comp.dcom.modems] US Robotics HST compatibles

laird@slum.MV.COM (Laird Heal) (09/21/90)

In article <1990Sep19.214021.17887@CAM.ORG>,  gammal@CAM.ORG (Michael Gammal) writes:

>Question:I use a Us Robotics Hst 9600/17.4k Modem....
>
>Are there any compatibles or compliants as one put it other than
>Us Robotics themselves.....

Not too prominently within the HST manual is: +1 800 DIAL-USR
which if you could call from Canada could answer the question.
Ask them if an other manufacturer has licensed it.

HST is a proprietary technology which US Robotics would have to
license to an alternate manufacturer.  As far as I know, nobody
has, while from time to time people refer to PEP-compatible
modems which license Telebit protocol spoofing and all.

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.
Can anyone give me some figures for rz/sz using PEP?

>
>Michael Gammal		Concordia University		gammal@Altitude.CAM.ORG

Hope you like the weather we keep sending you...

-- 
Laird Heal	laird@slum.MV.COM	The world is my office.
(Salem, NH)	+1 603 898 1406	<-----I charge for opinions, though.

izot@zswamp.fidonet.org (Geoffrey Welsh) (09/22/90)

 > 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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larry@nstar.uucp (Larry Snyder) (09/24/90)

laird@slum.MV.COM (Laird Heal) writes:


>a little faster than the real-world transfer rate of Telebits.
>Can anyone give me some figures for rz/sz using PEP?

We have a combination of PEP/HST modems and get 1650 cps using
the HST - and 1430 cps using the PEP modems (sending compressed files).


-- 
       Larry Snyder, Northern Star Communications, Notre Dame, IN USA 
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