kishon@yale-zoo-suned..arpa (Amir Kishon) (01/21/88)
I will be very glad if some one can tell me the differences between
USRobotics Courier 2400 and USRobotics Courier 2400E ?
-amir kishon
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ARPA: kishon@cs.yale.edu
BITNET: kishon@yalecs
UUCP: ...{decvax}!yale!kishon
-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_chapman@eris (Brent Chapman) (01/22/88)
In article <21676@yale-celray.yale.UUCP> kishon@yale-zoo-suned.UUCP (Amir Kishon) writes: >I will be very glad if some one can tell me the differences between >USRobotics Courier 2400 and USRobotics Courier 2400E ? The USR 2400E is a USR 2400 with MNP error correction built-in (level 3, I believe, from a quick skim of the manual). That's the major difference. -Brent -- Brent Chapman Capital Market Technology, Inc. Senior Programmer/Analyst 1995 University Ave., Suite 390 {lll-tis,ucbvax!cogsci}!capmkt!brent Berkeley, CA 94704 capmkt!brent@{lll-tis.arpa,cogsci.berkeley.edu} Phone: 415/540-6400
ritzenth@bgsuvax.UUCP (Phil Ritzenthaler) (01/22/88)
In article <21676@yale-celray.yale.UUCP>, kishon@yale-zoo-suned..arpa (Amir Kishon) writes: > I will be very glad if some one can tell me the differences between > USRobotics Courier 2400 and USRobotics Courier 2400E ? If I'm not mistaken (I spoke to US Robotics about a month ago about this), the 2400E has not only a different circuit board but also has MNP protocol. UNFORTUNATELY, because of the different circuitry, a 2400 CANNOT be upgraded to a 2400E . . . pity. Phil Ritzenthaler |USnail: University Computer Services Computer Graphics Research Consultant | 241 Math-Science Bldg. UUCP :.!cbosgd!osu-cis!bgsuvax!ritzenth | Bowling Green State University CSNET: ritzenth@bgsu.edu | Bowling Green, OH 43403-0125 ARPA : ritzenth%bgsu.edu@relay.cs.net | Phone: (419) 372-2102
dnelson@ddsw1.UUCP (Douglas Nelson) (01/25/88)
The Courier HST that I use at work has the capibility of communicating with the Courier 2400e with the MNP/ARQ error correction protocols mentioned earlier. At 9600, the MNP/ARQ correction is a blessing. Communication half- way across the country at 9600 baud I can pick up the phone and literally scream into it (and catch a few strange looks from fellow workers, :-) ) and get absolutely no line noise. The problem that occurs with the 2400e is that the error correction slows down the baud rate to about 1800 or so, and makes input that is staged (ie: stop-go-stop) VERY jumpy. Althogh it isn't too bad at 9600, at 2400 with the error checking it could easily drive you insane. Although I currently use the USRobotics Courier HST 9600, I used the regular Courier 2400 (without error checking) for a long time previous and have had excellent results. I don't think that the errors encounted at 2400 are significant enough to account for the difference in price nor the abnormal performance, unless you have extremely specific applications which would require ascii or otherwise text transmission in which an error could provide fatal. Hope this helps. ------------------ Douglas Nelson dnelson@ddsw1.UUCP ------------------
csg@pyramid.pyramid.com (Carl S. Gutekunst) (02/01/88)
>...the 2400E has not only a different circuit board but also has MNP protocol. Yeah, it's MNP level 3, according to the manual. >UNFORTUNATELY, because of the different circuitry, a 2400 CANNOT be upgraded >to a 2400E . . . pity. Also unfortunately, the 2400E is a lot less reliable than a 2400. We ordered ten Courier 2400 units about two years ago, and have had only one flakey one in the whole lot. (For a $300 modem, I call that excellent. Granted they all were temperature sensitive, but that was easy to deal with.) We recently bought ten 2400E units, based on rave reviews from customers and friends. At least half are having problems, and they are of the flakey inter- mittent variety: random hangups, random crashes, random modem confusion. Problems are much more frequent when using MNP, and the MNP implementation itself seems marginal. We have a number of local MNP sites that Racal-Vadic and Telebit modems talk to just fine, but the Couriers never sync up, or will complete one MNP call and then need a power-cycle before making new MNP calls. <csg>