Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!iuvax!purdue!bu-cs!encore!xylogics!loverso From: loverso@Xylogics.COM (John Robert LoVerso) Newsgroups: comp.dcom.modems Subject: Re: Microcom QX/V.32c evaluation Message-ID: <6906@xenna.Xylogics.COM> Date: 14 Aug 89 18:15:49 GMT References: <361@larouch.UUCP> <12332@s.ms.uky.edu> Reply-To: loverso@Xylogics.COM (John Robert LoVerso) Organization: Xylogics, Inc., Burlington MA Lines: 47 As another datapoint, I've had abysmal results with all the Microcom modems I've tested. Back in June, I had a pair of QX/V.32cs. They worked fine inside the building and from home. I brought one with me to the Baltimore USENIX and I couldn't get it to connect to its twin sitting back here in our machine room, at ANY speed. However, an internal 2400 baud modem in a laptop had no problem talking to the QX/V.32c back here, using the same phone line! When I brought the modem back here, it worked fine. At the same time, we had flawless performace from the Telebit T2500s that were being used in the terminal room. > ... > The [Baltimore USENIX] terminal room was run off a T2500 ... I don't > know what baud rate and/or compression was used. > ... Just for the record, both sides were at 9600 and were using Van Jacobson's header compression code, one end on a Sun3 and the other on an Annex. For most of the show, the Sun3 sitting in the terminal room was using a SLIP link at 38400 to the Annex (since there was no Ethernet at all in the room). I recently had a pair of Microcom QX/3296s on evaluation. These do MNP.6, as opposed to the MNP.9 on the QX/V.32c. They do have a "uucp spoofing mode", or so the manual says. It just lists the command to turn it on, but says nothing about what it does. I was interested in trying it, given that the QX/V.32c was beaten by a Trailblazer-Plus in terms of throughput over a UUCP connection. When I first unpacked the QX/3296s, one of them was acting flakey because about 99% of the time it wouldn't pick up the phone line when given a dial command (i.e., it couldn't get a dialtone - I'd hear the relay go off hook, but I'd get nothing on the speaker - plugging in a phone got me a dialtone). All of a sudden [no good reason why - I hadn't changed any switches or configuration], it started working fine. I got the pair to work and was somewhat satisfied with the performance. I put the previously flakey one in my machine room and took the other one home. When I got home, the modem would no longer pass self test. To make a long story shorter - we're buying T2500s. I've never had problems like this with my Trailblazers. -- John Robert LoVerso Xylogics, Inc. 617/272-8140 loverso@Xylogics.COM Annex Terminal Server Development Group encore!xylogics!loverso [formerly of Encore Computer Corp]