wb8foz@mthvax.cs.miami.edu (David Lesher) (12/03/90)
Folks, We're preaching to the choir. We know how well the Blazers work. Now, neither Byte or PC mag believes in email unless it is on their own profit_making system, but don't I recall that PeeSea Mag's is hosted on Compu$pend? If any one can uncover their 7xxx,yy address, we could let Bill Monochrome know what we do. (I'm SURE karl at the osu--Compu$pend link will KILL me for this idea. I just got a note back saying he had several THOUSAND pieces of mail backlogged already!) -- A host is a host from coast to coast.....wb8foz@mthvax.cs.miami.edu & no one will talk to a host that's close............(305) 255-RTFM Unless the host (that isn't close)......................pob 570-335 is busy, hung or dead....................................33257-0335
kjh@pollux.usc.edu (Kenneth J. Hendrickson) (12/03/90)
In article <1990Dec03.011952.15024@mthvax.cs.miami.edu> wb8foz@mthvax.cs.miami.edu (David Lesher) writes: >We're preaching to the choir. We know how well the Blazers work. How well does the T2500 work in V.32 mode? Does it have V.42? V.42bis? Does the T2500 have V.22bis for 2400 bps? V.22 for 1200 bps? 212A for 1200 bps? Bell 103 for 300 bps? How well does the T2500 work in V.22bis mode (2400 bps)? (I don't need PEP now, but I'm willing to pay more for a modem that actually works. I'm returning the Practical Peripherals PM9600SA.) What is the receiver sensitivity? -- Does anybody have these specs for the Practical Peripherals PM9600SA? Practical Peripherals was obviously so ashamed of their specs that they declined to publish them in TFM. -- favourite oxymorons: student athlete, military justice, mercy killing Ken Hendrickson N8DGN/6 kjh@usc.edu ...!uunet!usc!pollux!kjh
silos@bench.sublink.ORG (Paolo Pennisi) (12/04/90)
From mine personal experience I always got very good links between my ATI 2400etc/e v22bis with v42bis and a T2500. I got once 579cps, transferring a C source of about 50k, with V42bis compression on. This is my 5c. contribute. Paolo Pennisi -- (ARPA) silos@bench.sublink.ORG Paolo Pennisi (BANG) ...!otello!bench!silos via Solari 19 (MISC) ppennisi on BIX & PTPOSTEL 20144 Milano ITALIA ----< S U B L I N K N E T W O R K : a new way to *NIX communications >-----
esmith@goofy.apple.com (Eric Smith) (12/04/90)
In article <28585@usc> kjh@pollux.usc.edu (Kenneth J. Hendrickson) writes: > How well does the T2500 work in V.32 mode? Pretty well. Not excellent, but good. > Does it have V.42? V.42bis? Yes, with caveats (I don't know the details here). > Does the T2500 have V.22bis for 2400 bps? V.22 for 1200 bps? > 212A for 1200 bps? Bell 103 for 300 bps? Yes to all of the above. > How well does the T2500 work in V.22bis mode (2400 bps)? Quite well, at least as good as anything else I've tried, and I've tried a lot. > What is the receiver sensitivity? Good question. How is this usually specified for modems? > Does anybody have these specs for the Practical Peripherals PM9600SA? > Practical Peripherals was obviously so ashamed of their specs that they > declined to publish them in TFM. Typical of companies that just throw modems together from chip sets. I only trust modems from companies that have real modem engineers. Speaking of which, maybe someone who is not affiliated with Apple can describe the quality of the Apple Data Modem 2400 (and others). :-) -- Eric L. Smith Opinions expressed herein do not necessarily reflect those esmith@apple.com of my employer, friends, family, computer, or even me! :-)
floyd@ims.alaska.edu (Floyd Davidson) (12/04/90)
In article <ESMITH.90Dec3231319@goofy.apple.com> esmith@goofy.apple.com (Eric Smith) writes: >In article <28585@usc> kjh@pollux.usc.edu (Kenneth J. Hendrickson) writes: > > >> What is the receiver sensitivity? > >Good question. How is this usually specified for modems? > Warning: Boring techie discussion of limited value follows: It may not be specified. I'll quote some figures off the top of my head, which is pointed, so the figures may be twisted. If I remember right most modems have an output of -10 Dbm and most of them claim to function with an input signal down to something like -45 Dbm (300 and 1200 bps modems, I don't know about others). The standard telephone line is expected to have a test tone level of 0 Dbm input and an output of -9 Dbm (sometimes this is set to -6 Dbm). The modem is using a data level of -10 Dbm0. (Ten db down from test tone level. It is interesting to note that leased lines use -13 Dbm0.) The received signal going into the modem would be -19 Dbm (if in fact you have a -9 Dbm receive level for a test tone, which is not likely -- -6 to -12 Dbm is likely). Ok so the modem expects -19, may get as much as -16, and is supposed to work at -45. That is a 29 Db range and most likely if you actually see a level vary over that range the modem will not work for other reasons (phase hits etc.). That is why you are not likely to see anyone bragging about modem sensitivity measurements. It doesn't mean much about how well the modem will handle bad lines. Much more interesting is whether the modem can handle a momentary change of say 6 Db or 3 Db up or down in the signal level. I have done trouble shooting on leased lines where the problem was the levels were 4 Db off and the modem could not handle it at all. That is really poor performance and causes no end of headaches if the end user, or some intermediate carrier, is in the habit of adjusting levels every month or two just to be sure. Once again, I'm not sure the figures I gave above for the modem output or the minimum receive signal are correct. It doesn't really make any difference. Floyd -- Floyd L. Davidson floyd@hayes.ims.alaska.edu Salcha, AK 99714 paycheck connection to Alascom, Inc. When I speak for them, one of us will be *out* of business in a hurry.