luce@aurs01.UUCP (J. Luce) (11/13/90)
I was just wondering about something here. I have seen a few times
questions regarding inexpensive modems but have never seen replies. I
too am interested in high speed V.32 type modems but just don't have the
money to buy a Telebit or Dual Standard and a $400+ mistake would be hard
for me to take. So, tell me, who has used and has info regarding
Practical Peripherals, Incomm, Intel 9600EX, etc. ? How well do they
work and do they in fact talk with different mfrs. V.32 modems...
Maybe I'm in the wrong field... if I switch from Real-Time S/W to Unix
Systems S/W, maybe I could afford a Telebit ;-{)zhou@brazil.psych.purdue.edu (Albert Zhou) (11/15/90)
Just ask a stupid question: Is it allowed to use 9600 baud on regular telephone line?
ralphs%halcyon.uucp@seattleu.edu (11/15/90)
zhou@brazil.psych.purdue.edu (Albert Zhou) writes: > Just ask a stupid question: Is it allowed to use 9600 baud on regular telepho > line? Sure.
cpcahil@virtech.uucp (Conor P. Cahill) (11/15/90)
In article <11481@j.cc.purdue.edu> zhou@brazil.psych.purdue.edu (Albert Zhou) writes: >Just ask a stupid question: Is it allowed to use 9600 baud on regular telephone >line? Yes, but if you have problems with line quality, the phone company is liable to laugh at you when you tell them you are trying to get 9600 baud on a standard line. -- Conor P. Cahill (703)430-9247 Virtual Technologies, Inc., uunet!virtech!cpcahil 46030 Manekin Plaza, Suite 160 Sterling, VA 22170
wb8foz@mthvax.cs.miami.edu (David Lesher,,255RTFM,255rtfm) (11/16/90)
>> Just ask a stupid question: Is it allowed to use 9600 baud on regular telepho >> line? Woop! Woop! Woop! It's the SWAT team: S peed W ay A bove T eletype Keep your fingers away from that keyboard, or they'll fill you full of X-off's and Deletes. Remember: You have the right to remain Silent 700 You have the right to a tractor feeder If you desire, but cannot afford one, too bad.... ;-}} Sorry, this week is starting to get to me..... -- 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
tnixon@hayes.uucp (Toby Nixon) (11/16/90)
In article <11481@j.cc.purdue.edu>, zhou@brazil.psych.purdue.edu (Albert Zhou) writes: > Just ask a stupid question: Is it allowed to use 9600 baud on regular telephone > line? Absolutely yes. FCC Part 68 doesn't, which governs connections to the telephone network, places no limitations on the speed you can transmit. It does govern the bandwidth and signal strength, but modems are designed to work within these limitations. People use 14,400bps and faster modulation on standard voice-grade dial-up phone lines every day, with excellent results. -- Toby Nixon, Principal Engineer | Voice +1-404-449-8791 Telex 151243420 Hayes Microcomputer Products Inc. | Fax +1-404-447-0178 CIS 70271,404 P.O. Box 105203 | UUCP uunet!hayes!tnixon AT&T !tnixon Atlanta, Georgia 30348 USA | Internet hayes!tnixon@uunet.uu.net
stasica@boulder.Colorado.EDU (Creeping Death) (11/17/90)
In article <1990Nov15.151916.16830@virtech.uucp> cpcahil@virtech.UUCP (Conor P. Cahill) writes: >In article <11481@j.cc.purdue.edu> zhou@brazil.psych.purdue.edu (Albert Zhou) writes: >>Just ask a stupid question: Is it allowed to use 9600 baud on regular telephone >>line? > >Yes, but if you have problems with line quality, the phone company is liable >to laugh at you when you tell them you are trying to get 9600 baud on >a standard line. What's wrong with 9600 on a standard phone line? I run an HST Dual Standard at 14.4k and have never had problems with phone lines. In fact, I have heard that a couple companies have got 57.4k modems to work on a phone line (well, maybe a fiber optic line...but many phone lines are nowdays). -- stasica@snoopy.Colorado.EDU
ralphs%halcyon.uucp@seattleu.edu (11/17/90)
stasica@boulder.Colorado.EDU (Creeping Death) writes: > What's wrong with 9600 on a standard phone line? I run an HST Dual Standard > at 14.4k and have never had problems with phone lines. In fact, I have heard > that a couple companies have got 57.4k modems to work on a phone line (well, > maybe a fiber optic line...but many phone lines are nowdays). Many years ago, I commented to a Pacific NorthWest Bell tech that we were using 19.2Kbaud modems over dialup phone lines locally, nationally, and internationally (this was when AT&T and PNB were 'one and the same'). The conversation moved to what was the maximum *supported* baudrate on AT&T's longlines, and he stated they were tested to 4800 baud. At that time we were getting 1360cps Telebit-to-Telebit inter and intra-state and about 900cps internationally (Germany and Australia) with >300K binary files, using streaming protocols. The modems were Telebit RA-12's. The local telco was using S6A (?) hot-carrier lines and newly installed SLCC 96's over 20-year old 24-26ga copper (the hot-carrier stuff appeared to put modulate analog voice data over a ~100-volt DC carrier, while the 96's were digital). The telco Central Office used something that had been around for a while before ESS was installed (mechanical, but not a #6 crossbar). Note, since then throughput using the same configuration dropped, with the advent of newer, more sophisticated satellite services. Fortunately, the modem manufacturers have released newer equipment that overcomes (to varying degrees) the communications services' 'enhancements' (kinda like reversing the air cleaner cover on your car to compensate for the loss of performance due to smog controls). The old hot-carrier lines gave way to the 96's and new 22ga copper, now buried, and a brand-new ESS CO.
larry@nstar (Larry Snyder) (11/19/90)
What type and speed of processor is in the Ultra 9600?
--
Larry Snyder, Northern Star Communications, Notre Dame, IN USA
{larry@nstar, {uunet|backbone}!nstar!larry, larry%nstar@iuvax.cs.indiana.edu}
backbone usenet newsfeeds available
Public Access Unix Site (219) 289-0282 (5 high speed lines)pj@pnet51.orb.mn.org (Paul Jacoby) (11/21/90)
I'm expecting my PP9600SA modem to arrive this week, and I am not totally clear on whether it supports/will support V.32bis. Yes? .-----------------------------------------------------------------------------. | UUCP: {crash tcnet}!orbit!pnet51!pj | Working with idiots keeps | | INET: pj@pnet51.orb.mn.org | my life interesting... | `-----------------------------------------------------------------------------'
larry@nstar (Larry Snyder) (11/21/90)
pj@pnet51.orb.mn.org (Paul Jacoby) writes: >I'm expecting my PP9600SA modem to arrive this week, and I am not totally >clear on whether it supports/will support V.32bis. Yes? No, it doesn't. -- Larry Snyder, Northern Star Communications, Notre Dame, IN USA {larry@nstar, {uunet|backbone}!nstar!larry, larry%nstar@iuvax.cs.indiana.edu} backbone usenet newsfeeds available Public Access Unix Site (219) 289-0282 (5 high speed lines)
benyukhi@motcid.UUCP (Ed Benyukhis) (11/22/90)
In article <29872@boulder.Colorado.EDU>, stasica@boulder.Colorado.EDU (Creeping Death) writes: > What's wrong with 9600 on a standard phone line? I run an HST Dual Standard > at 14.4k and have never had problems with phone lines. In fact, I have heard > that a couple companies have got 57.4k modems to work on a phone line (well, > maybe a fiber optic line...but many phone lines are nowdays). 57 Kbps on the voice grade line that is band limited to 3.4 Khz is contrary to both Shannon and Nyquist rules. Ed Benyukhis
schuster@cup.portal.com (Michael Alan Schuster) (11/22/90)
>I'm expecting my PP9600SA modem to arrive this week, and I am not totally >clear on whether it supports/will support V.32bis. Yes? Absolutely, positively, no! At some future date, when Rockwell releases a V.32bis card to replace the R9696 card in your PP9600, it might be possible to upgrade by replacing half the guts of your modem.
root@infoac.rmi.de (INFOAC-Operator) (11/24/90)
ralphs%halcyon.uucp@seattleu.edu writes: >zhou@brazil.psych.purdue.edu (Albert Zhou) writes: >> Just ask a stupid question: Is it allowed to use 9600 baud on regular telepho >> line? >Sure. That depends on where you live ...... Rupert -- ***************************************************************** ___ ____ ___ _ _ ___ ___ ___ ___ ___ ___ _ _ /__/ / / / / /\ / /__ / /__//__// /__//__ /\ / / \ / / __/_ / / /__ / / // //__ / //__ / /
pj@pnet51.orb.mn.org (Paul Jacoby) (11/24/90)
[in reference to my question "will the PP9600SA support V.32bis?"] > > At some future date, when Rockwell releases a V.32bis card to > > replace the R9696 card in your PP9600, it might be possible to > > upgrade by replacing half the guts of your modem. Ok, then the next question becomes, "Should I care?" I didn't realize that such an upgrade would be as nasty as replacing the entire R9696. Ouch. .-----------------------------------------------------------------------------. | UUCP: {crash tcnet}!orbit!pnet51!pj | Working with idiots keeps | | INET: pj@pnet51.orb.mn.org | my life interesting... | `-----------------------------------------------------------------------------'
ralphs%halcyon.uucp@seattleu.edu (11/24/90)
root@infoac.rmi.de (INFOAC-Operator) writes: > ralphs%halcyon.uucp@seattleu.edu writes: >>zhou@brazil.psych.purdue.edu (Albert Zhou) writes: >>> Just ask a stupid question: Is it allowed to use 9600 baud on regular >>Sure. > That depends on where you live ...... Yes, true and we covered that via email. The trap that the fellow wasn't asking about U.S. phone lines caught me. However, in the U.S. I would stand by the statement that you are allowed to use 9600 on regular phone lines. I would imagine there are countries in existence where baud rate is legislated by some entity.
schuster@cup.portal.com (Michael Alan Schuster) (11/24/90)
[in reference to my question "will the PP9600SA support V.32bis?"] > > At some future date, when Rockwell releases a V.32bis card to > > replace the R9696 card in your PP9600, it might be possible to > > upgrade by replacing half the guts of your modem. >Ok, then the next question becomes, "Should I care?" I didn't realize that >such an upgrade would be as nasty as replacing the entire R9696. Ouch. It depends on what your priorities are. If you need to establish V.32 connections =now=, then you might not care. If you must have the latest and greatest, you might want to wait a while ... at least long enough to find out what upgrade policies, if any, will be announced. Intel doesn't know what V.32bis is ... PP is looking at it ... USR will probably try to sell you a whole new modem after taking your old one as a "trade in". Hayes ... dunno. Toby Nixon is probably listening, so perhaps we'll get an answer from Hayes :-)
kim@Software.Mitel.com (Kim Letkeman) (11/26/90)
In article <1990Nov23.212221.20530@infoac.rmi.de> root@infoac.rmi.de (INFOAC-Operator) writes: | ralphs%halcyon.uucp@seattleu.edu writes: | | >zhou@brazil.psych.purdue.edu (Albert Zhou) writes: | | >> Just ask a stupid question: Is it allowed to use 9600 baud on regular telepho | >> line? | | >Sure. | | That depends on where you live ...... | | Rupert Why is it that people insist on wasting bandwidth with answers that merely provide a hook, rather than any useful information? Are we supposed to wait for the book to come out? Come on Rupert. Provide the details or don't bother posting. Apologies if this is too strongly worded, but it sure gets tiring to see these one liners .... -- Kim Letkeman kim@software.mitel.com uunet!mitel!spock!kim
lstowell@pyrnova.pyramid.com (Lon Stowell) (12/05/90)
In article <5435@navy19.UUCP> benyukhi@motcid.UUCP (Ed Benyukhis) writes: >57 Kbps on the voice grade line that is band limited to 3.4 Khz is contrary >to both Shannon and Nyquist rules. > > >Ed Benyukhis Maybe so, but the POTS line, with its 3.4 Khz limit can easily handle 160 Kbit/second or so rates. ISDN easily places 144 Kbit USER rate on this 2-wire line, using 2B1Q signalling... Don't confuse the Nyquist limit on "baud" or carrier signalling interval over 3.4 KHz with the ability to encode and decode user information as multiple bits/baud over the bandwidth limited channel... 38.4 USER rate works quite nicely over V.32 modems by using Trellis (5:4 redundancy) and QAM (4:1) signalling at a baud rate of only 1200 on the analog channel...although the "raw" bit rate is only 9600...and V.32bis will push this to 14.4 raw rate,,,should be able to use data compression to get 57.6 out of a V.32bis modem easily...
grr@cbmvax.commodore.com (George Robbins) (12/05/90)
In article <136548@pyramid.pyramid.com> lstowell@pyrnova.pyramid.com (Lon Stowell) writes: > In article <5435@navy19.UUCP> benyukhi@motcid.UUCP (Ed Benyukhis) writes: > >57 Kbps on the voice grade line that is band limited to 3.4 Khz is contrary > >to both Shannon and Nyquist rules. > Maybe so, but the POTS line, with its 3.4 Khz limit can easily > handle 160 Kbit/second or so rates. ISDN easily places 144 Kbit > USER rate on this 2-wire line, using 2B1Q signalling... Are you sure you're not confusing the wires with the bandwidth? The standard local loop cables can handle a much wider bandwith than the 3.4 KHz nominal channel width. The nominal bandwidth is imposed by various devices used to optimize the longer loops for voice transmission, analog components in the central office and the channelized multiplexing and bandwidth limited digitizing used in the long distance network and digital switches. There is also a secondary regulatory issue - when the telco supplies a pair of wires for a connection to the direct dial network, one set of bandwidth and signal level rules apply, when a similar pair of wires from the same cable is offered for other purposes, these particular rules no longer apply. > Don't confuse the Nyquist limit on "baud" or carrier signalling > interval over 3.4 KHz with the ability to encode and decode user > information as multiple bits/baud over the bandwidth limited > channel... 38.4 USER rate works quite nicely over V.32 modems > by using Trellis (5:4 redundancy) and QAM (4:1) signalling at a > baud rate of only 1200 on the analog channel...although the > "raw" bit rate is only 9600...and V.32bis will push this to 14.4 > raw rate,,,should be able to use data compression to get 57.6 > out of a V.32bis modem easily... All that is nice, but I think you'll also find that if the data can be compressed then it's statistical properties are less than optimal, i.e. the information is poorly encoded. It seems that Nyquist and Shannon still rule, but as with's Einstein's theory of relativity, a quick grasp of some of the features of the theory do not convey the complete understanding of the implications of the theory or the conditions. I might tend to agree with the orignal poster in the sense that any modem will have real trouble giving 56KBPS with random data over arbitrary direct dial connections - first of all the notion that 4:1 compression is normal is bogus, 2:1 is typical of normal text, while random data doesn't compress at all - second there is are real theoretical limits on data throuput versus channel quality that sooner or later intersect with the properties of real-world direct dial connections. Right now there seems to be pessimism as far as getting past the 14K-19.2KBPS range of real thruput. I don't claim to know what the theroretical limits are, but I'm happy to have modems that compress or take advantage of unusually good connections as long as they offer good thruput under impaired conditions and reliable operation under any conditions. V.32 seems a bit marginal in these terms, but V.32bis may consitute a real improvement, not just because it's "faster", but also because it's more agile. In the meantime, my Trailblazers work reasonably well, not because they do anything magical or really sophisticated, but because they adapt well to (most) real world line conditions and implement (reasonably) rugged protocols and error control techniques. -- George Robbins - now working for, uucp: {uunet|pyramid|rutgers}!cbmvax!grr but no way officially representing: domain: grr@cbmvax.commodore.com Commodore, Engineering Department phone: 215-431-9349 (only by moonlite)
koch@motcid.UUCP (Clifton Koch) (12/07/90)
From article <136548@pyramid.pyramid.com>, by lstowell@pyrnova.pyramid.com (Lon Stowell):
-> In article <5435@navy19.UUCP> benyukhi@motcid.UUCP (Ed Benyukhis) writes:
->>57 Kbps on the voice grade line that is band limited to 3.4 Khz is contrary
->>to both Shannon and Nyquist rules.
->>
->>
->>Ed Benyukhis
->
->
-> Maybe so, but the POTS line, with its 3.4 Khz limit can easily
-> handle 160 Kbit/second or so rates. ISDN easily places 144 Kbit
-> USER rate on this 2-wire line, using 2B1Q signalling...
You're comparing apples to oranges. First, the 3.4 Khz limit is not imposed
by the wires themselves. It's imposed by the transmission methods of voice
data. Second, the rates you quote are accomplished by quite different
transmission methods. They used direct digital data transfer rather than
encoding data into audio tones.
-> Don't confuse the Nyquist limit on "baud" or carrier signalling
-> interval over 3.4 KHz with the ability to encode and decode user
-> information as multiple bits/baud over the bandwidth limited
-> channel... 38.4 USER rate works quite nicely over V.32 modems
-> by using Trellis (5:4 redundancy) and QAM (4:1) signalling at a
-> baud rate of only 1200 on the analog channel...although the
-> "raw" bit rate is only 9600...and V.32bis will push this to 14.4
-> raw rate,,,should be able to use data compression to get 57.6
-> out of a V.32bis modem easily...
Maybe if you send a bunch of nulls. I haven't seen any compression
algorithms that can manage that big of a compression on even simple text
files (on the fly, at least). But we're not really talking compression
here. The true data rate is the amount of worst case (i.e. uncompressable)
data you can send. Most of my modem sessions are with already compressed
files, and I keep compression turned off because I get less throughput due
to the header overhead of the compression scheme.
Nyquists theorm does limit the basic baud rate of the information sent,
but baud rate doesn't have much to do with data rate. Several bits
can be encoded (relatively) easily within each transition change, but there
is a theoretical limit to this also.
--
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