Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!wuarchive!zaphod.mps.ohio-state.edu!mips!apple!coherent!dplatt From: dplatt@coherent.com (Dave Platt) Newsgroups: comp.dcom.modems Subject: Re: Where can I buy Telebit (or other modems) cheap? Message-ID: <47352@improper.coherent.com> Date: 21 Feb 90 06:41:56 GMT References: <8377@potomac.ads.com> <1358@bridge2.ESD.3Com.COM> Reply-To: dplatt@coherent.com (Dave Platt) Organization: Coherent Thought Inc., Palo Alto CA Lines: 95 In article <1358@bridge2.ESD.3Com.COM> ngg@bridge2.ESD.3Com.COM (Norman Goodger) writes: > 1. There is no such thing as a cheap Telebit. Nor are they inexpensive ;-} > 2. The USR Courier HST 14.4 modem is faster than a Telebit. That may be true for straight interactive sessions... although I believe I've read that the Telebit PEP protocol can yield roughly 14 kbits/second in true throughput to the user. The T-1000 doesn't go that quickly, though. My impression is that the T-2000/T-2500 running in PEP mode, and the HST 14.4 modems, provide roughly equivalent throughput when streaming large amounts of already-compressed data (.ARC or .SIT or .Z files). If you need to run vanilla (short-packet) XMODEM or Kermit file transfers over a high-speed line, there's no contest... the Telebit protocol-spoofing eliminates most of the line-turnaround delay. Spoofed transfers really scream! > 3. Depending on your specific needs, in the BBS world there are > far more HST's out there than Telebits. Absolutely true... if you want to go BBS-hopping, an HST-protocol modem is the way to go. If you want UUCP protocol support, a Telebit is the way to go. If you want to run SLIP, a V.32 modem is probably the way to go. > 4. For the somewhere near the same $$ you can buy a USR HST dual Standard > and get HST and V.32 compatability and still be faster than Telebit. Hmmm. About six months ago we bought a couple of HST Dual Standard modems and paid about $1100 each, I think. T-2500 modems are available for about that price, as I recall... they also support V.32. > 5. The Telebit modems are notoriously hard to setup, they have more > registers than I care to think about.. They do take some careful setup to work best, it's true. Once they're set up, they don't seem to need much tuning. Also, the newer Telebit modems can support two different configurations in nonvolatile memory, with an A/B switch on the front panel. This can save a lot of typing, if you switch back and forth between a couple of different modes. > Bottom line...if you want speed, get an HST... Well... it depends on what you're doing. And, speed isn't everything. Reliability is another important factor. I've been using our HST Dual Standard modems for about six months. I do like them, quite a lot, in the tasks for which I've been using them. Both the HST protocol and the V.32 protocol support work nicely... most of the time. However... one of our people took our roving HST/DS modem home to San Jose (20 miles or so) and tried to use it to log in via my workstation. We spent several days in EXTREME frustration. He would dial up, my modem would answer, the two modems would scream at each other for several seconds, and then drop carrier. They would NOT successfully complete handshaking... not in V.22bis mode, nor in V.32 mode, nor in HST mode! Nada! He plugged in a USR Courier 2400e modem and tried again... it connected to my HST/DS without hesitation. He brought his HST/DS in, and I tested it via a local phone call to my workstation, with exactly the same configuration... it worked perfectly. I tried it from my house (5 miles) and from a client's building (15 miles)... worked perfectly. But, from his house in San Jose, he could not establish a connection at any speed! His line is somewhat noisy, it's true... but the $1100 HST Dual Standard was unable to establish a connection that a $400 Courier made without even blinking. I suspect that the HST Dual Standard _really_ wants to work over a clean line. On the other hand... the Telebit PEP protocol has won acclaim for its ability to set up and maintain connections over incredibly cruddy lines. People have reported stable connections, and 800 CPS throughut, over lines that were so noisy that 1200 bps connections (Bell 212) and 2400 bps connections (V.22bis) were unusable. PEP modems will keep a connection going even if you pick up an extension phone and shout "Hello, Polly Parrot! I've got a nice fresh cuttlefish for you!" into the mouthpiece. I'd strongly suggest that anyone thinking of buying a high-speed dialup modem arrange to test-drive the modems under consideration, before making any irrevocable decision to purchase. -- Dave Platt VOICE: (415) 493-8805 UUCP: ...!{ames,apple,uunet}!coherent!dplatt DOMAIN: dplatt@coherent.com INTERNET: coherent!dplatt@ames.arpa, ...@uunet.uu.net USNAIL: Coherent Thought Inc. 3350 West Bayshore #205 Palo Alto CA 94303