Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!gem.mps.ohio-state.edu!apple!bionet!sdsu!crash!pnet01!scotto From: scotto@pnet01.cts.com (Scott O'Connell) Newsgroups: comp.dcom.modems Subject: Re: Help - trailblazer not connecting in "fast" mode Message-ID: <441@crash.cts.com> Date: 26 Sep 89 23:16:08 GMT Sender: root@crash.cts.com Organization: People-Net [pnet01], El Cajon CA Lines: 32 > re: modem won't connect in fast mode but does at 2400 etc. I had the same problem here in San Diego. Worse yet it was while I was evaluating v.32 modems. I tried them on a couple o f lines and still the best I could do was 2400. After many weeks of firmware changes, modem paramaters and hours of frustration Telebit (one of the modems I was evalMY}uating) set up a Spectrum Analyzer and found the problem. It was easy to spot because the PEP sends out a narrow pilot tone. If there is a loss on the line in that area the modem doesn't hear the other modem. This was complicated by my V.32 testing which uses a much wider pilot tone. Anyway, the phone company didn't understand the problem, said that the line was within specs and left. I found a line that worked, had them do a comparison and they said "No difference". Then they started swapping pairs and discovered the problem followed a short strech of underground cable about 5 miles from my office and 2 miles from the CO. They swapped that section for another pair and everything is working fine. If it hadn't been for Telebit tech support I'd have been completely frustrated and settled for staying at 2400. I'm glad they took the time to help out. If anyone is interested, I have prints of the spectrum analyzer results that Telebit did. I also would recommend talking to Lisa Masnaghetti at Telebit and reminding her of my problem. -- Scott O'Connell Scott O'Connell - Datagram Corp. UUCP: {hplabs!hp-sdd sdcsvax nosc}... 3297 Sweetwater Springs Blvd #8 ...!crash!pnet01!scotto San Diego, CA 92078-1477 ARPA: crash!pnet01!scotto@nosc.mil 800/235-5030 INET: scotto@pnet01.cts.com