POTS line quality help
in [Design]
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From: denali on 30 Apr 2010 19:05 On Apr 30, 12:59 am, Martin Brown <|||newspam...(a)nezumi.demon.co.uk> wrote: > Michael A. Terrell wrote: > > Martin Brown wrote: > >> Michael A. Terrell wrote: > >>> started disappearing over 25 years ago in the US. My first encounter was > >>> when the phone company ripped out a leased pair between a fire station & > >>> their siren at a paper mill a half mile away. That caused a mad > >> If you had a leased line from the telco then they have to provide a > >> functionally equivalent replacement service over a virtual circuit. What > >> you say does not make sense. > > > It's simple. They were using it as a simple low voltage, current > > limited remote switch which wasn't guaranteed by the contract, but the > > Then the phone company was entirely within their rights to snip it. > > > > > > > phone company knew it was there and let them get away with it for > > decades. Prior to that the dispatcher had to call the factory to have > > the siren activated by an employee. A leased line was still available, > > but was no longer a direct copper path between the two buildings. > > Technology moves on, and old equipment is retired as it happens. Since > > a lot of small departments had to move to radio control, the county set > > up a county wide control system so they could set off the siren > > directly. the could chose a single station, a small group, or in a > > disaster, every station in the county. > > >> I don't see what the problem is. The end > >> user never knows what the details of the local exchange technology is. > > >> Or are you saying that some cowboys from the fire service way back when > >> piggybacked a siren connection into telco circuit trunking and telco > >> snipped the cables when the upgraded to fibre optics? > > > Fiber to the premise in the '80s? Dream on! > > That seemed to be what you were claiming. We had internal fibre links on > campus as a part of one of the earliest WANs in the early 1980's. > > >>> scramble to convert it (and others) to remote control by VHF radio. > >>> That took over $1000 out of the volunteer fire department's budget. > >> Why could you not continue with telco leased line service? > > > It was no longer compatible with a simple SPST wall mounted switch > > across the line. > > So you were using a spurious feature that was not supported by the > telco. Pretty much as I suspected a prehistoric jerry rigged cowboy > wiring solution that they did not guarantee to support. > > Regards, > Martin Brown You're overly critical. The DC signal channel was an offered service throughout the Bell System. I probably even have a copy of the Technical Publication somewhere.
From: denali on 30 Apr 2010 19:05 On Apr 29, 1:47 pm, "Michael A. Terrell" <mike.terr...(a)earthlink.net> wrote: > Martin Brown wrote: > > > Michael A. Terrell wrote: > > > Martin Brown wrote: > > >> Michael A. Terrell wrote: > > >>> Martin Brown wrote: > > >>>> denali wrote: > > >>>>> On Apr 27, 12:08 am, Martin Brown <|||newspam...(a)nezumi.demon.co.uk> > > >>>>> wrote: > > >>>>>> denali wrote: > > >>>>>>> FYI, RE: JB's post.. leased line parameters are in no way applicable > > >>>>>>> to switched services. Forget about 3002 channels, etc. > > >>>>>>> Since you had better data service that has become degraded, something > > >>>>>>> is clearly wrong somewhere. > > >>>>>> Not wrong. Different. He should force a V34+ connection and see if that > > >>>>>> behaves any better - but he doesn't listen to advice. > > > >>>>>> Most likely one of his neighbours has moved to ADSL and the engineers > > >>>>>> have pinched his real copper circuit for that. Multiplexed local lines > > >>>>>> do not carry 56k signals at all well. The older analogue technology > > >>>>>> modems are a bit more robust in that environment. > > > >>>>>> Regards, > > >>>>>> Martin Brown > > >>>>> Your 56k comment is correct, but the point here is that he can't even > > >>>>> to 28.8, which narrows the likely problem/solution. Nothing is gained > > >>>>> by considering your point. > > > >>>>> D > > >>>> The telco frees up a real copper circuit for a higher value customer, > > >>>> and puts the cheapskates with basic phone only onto shared multiplexed > > >>>> lines. That destroys 56k and derivatives functioning at anything like > > >>>> full speed. V34+ will work better if the problem is as I describe. > > > >>> Real copper? A lot of the US has gone to Fiber optics to within a > > >>> mile or two of your home. I haven't seen much copper in Florida for > > >>> close to 20 years, except for the 'last mile'. > > >> The guy clearly lives in the boonies and doesn't have two pennies to rub > > >> together. It is entirely reasonable to assume that their local phone > > >> system is antique and decrepit. The "fault" he describes is identical to > > >> the problems people on multiplexed voice only lines experienced when 56k > > >> technology was rolled out. That is why I referred him to that old FAQ. > > > >> Most places in the UK are fibre up to the local exchange, but the last > > >> few miles is copper. Utilities are fighting tooth and nail in rural > > >> areas to avoid putting in any extra copper. That means as lines fail and > > >> more and more people get ADSL the remaining few on voice only lines are > > >> multiplexed in a black box somewhere between the exchange and their > > >> home. Answers.com has a description of the technology at about the right > > >> level for the OP to understand. > > > >>http://www.answers.com/topic/pair-gain > > > > Pair Gain isn't cheap in the US. Copper from the house to the CO > > > Pair gain is a heck of a lot cheaper than running new cables to the > > exchange in sparsely populated rural areas (which the US has a lot of). > > > > started disappearing over 25 years ago in the US. My first encounter was > > > when the phone company ripped out a leased pair between a fire station & > > > their siren at a paper mill a half mile away. That caused a mad > > > If you had a leased line from the telco then they have to provide a > > functionally equivalent replacement service over a virtual circuit. What > > you say does not make sense. > > It's simple. They were using it as a simple low voltage, current > limited remote switch which wasn't guaranteed by the contract, but the > phone company knew it was there and let them get away with it for > decades. Prior to that the dispatcher had to call the factory to have > the siren activated by an employee. A leased line was still available, > but was no longer a direct copper path between the two buildings. > Technology moves on, and old equipment is retired as it happens. Since > a lot of small departments had to move to radio control, the county set > up a county wide control system so they could set off the siren > directly. the could chose a single station, a small group, or in a > disaster, every station in the county. > > > I don't see what the problem is. The end > > user never knows what the details of the local exchange technology is. > > > Or are you saying that some cowboys from the fire service way back when > > piggybacked a siren connection into telco circuit trunking and telco > > snipped the cables when the upgraded to fibre optics? > > Fiber to the premise in the '80s? Dream on! > > > > scramble to convert it (and others) to remote control by VHF radio. > > > That took over $1000 out of the volunteer fire department's budget. > > > Why could you not continue with telco leased line service? > > It was no longer compatible with a simple SPST wall mounted switch > across the line. > Telco's, USWEST/QWEST included, running out of inter-office copper, had to "grandfather" the metallic 0-15 DC signal channel and discontinued the offering. It was replaced by voice-grade signal channel, and the customer had to provide their own tone hardware. Later, customers were advised of a date on which even the grandfathered channels would be discontinued.
From: JosephKK on 30 Apr 2010 22:38 On Fri, 30 Apr 2010 12:28:08 -0700, Robert Baer <robertbaer(a)localnet.com> wrote: >JosephKK wrote: >> On Wed, 28 Apr 2010 16:45:04 -0700, Robert Baer <robertbaer(a)localnet.com> >> wrote: >> >>> Robert Baer wrote: >>>> JosephKK wrote: >>>>> On Tue, 27 Apr 2010 11:39:06 -0700, Robert Baer <robertbaer(a)localnet.com> >>>>> wrote: >>>>> >>>>>> Martin Brown wrote: >>>>>>> Robert Baer wrote: >>>>>>>> Martin Brown wrote: >>>>>>>>> denali wrote: >>>>>>>>>> FYI, RE: JB's post.. leased line parameters are in no way applicable >>>>>>>>>> to switched services. Forget about 3002 channels, etc. >>>>>>>>>> >>>>>>>>>> Since you had better data service that has become degraded, >>>>>>>>>> something >>>>>>>>>> is clearly wrong somewhere. >>>>>>>>> Not wrong. Different. He should force a V34+ connection and see if >>>>>>>>> that behaves any better - but he doesn't listen to advice. >>>>>>>>> >>>>>>>>> Most likely one of his neighbours has moved to ADSL and the >>>>>>>>> engineers have pinched his real copper circuit for that. >>>>>>>>> Multiplexed local lines do not carry 56k signals at all well. The >>>>>>>>> older analogue technology modems are a bit more robust in that >>>>>>>>> environment. >>>>>>>>> >>>>>>>>> Regards, >>>>>>>>> Martin Brown >>>>>>>> Well,now if i KNEW how to force V34+ i would try. >>>>>>> You should pay more attention to the postings in this thread and >>>>>>> also ask on comp.modems and/or us.telecom or whatever it is called. >>>>>>> They will know where you can dial into for a DIY line bandwidth >>>>>>> test. Assuming that end users are allowed to do such things in "the >>>>>>> land of the free". >>>>>>> >>>>>>> You might find a prehistoric early 56k UK FAQ helpful in trying to >>>>>>> configure your modem to work retro style. >>>>>>> >>>>>>> http://www.pierrot.demon.co.uk/faq/dtm.faq >>>>>>> >>>>>>> (it is well out of date and UK based but still has good hints) >>>>>>> >>>>>>> Regards, >>>>>>> Martin Brown >>>>>> I have that UK reference and it is interesting and a bit informative. >>>>>> I have TerraTerm Pro but i cannot use it with my ISP to do any >>>>>> testing. >>>>>> If i ATDTetc in, that works and see the prompt for username but +++ >>>>>> does not escape to modem; if i am online like now, TerraTerm barfs. >>>>>> So _that_ type of testing is out unless there is another number or >>>>>> alternate to try. >>>>>> One of the suggested tests was with >>>>>> http://www.whichvoip.com/voip/speed_test/ppspeed.html and jitter was >>>>>> 610mSec, packet loss of 0%, MOS score (whatever that is) of 2.9, >>>>>> download speed 26.2K, upload speed of 21.5k and QOS at 92%. >>>>>> Measured loop current 35mA, different US Robotics modem acts the same. >>>>> OK. It seems that TerraTerm Pro is part of the problem. XP comes with >>>>> a properly primitive terminal program though. You might try that. >>>> Do not use XP, but maybe a similar prog is available with Win98SE; >>>> will look for it. >>>> Thanks. >>> Found HyperTerm for Win98SE, it seemed to be installed but did not work. >>> So..uninstall, reboot, install and it works.. >>> .. sort-of. >>> ATDT972-231-0633 >>> (wait a bit) >>> +++ >>> AT%L%Q >>> ERROR >>> AT&V1 >>> ERROR >>> AT&L >>> ERROR >>> ATO >>> (am now back online with isp asking for username and password) >>> So, STILL cannot get info! >>> What next? >> >> OK i started here: >> >> Google: "at command set" Which finds many things with these being on the >> first page >> >> http://en.wikipedia.org/wiki/Hayes_command_set >> http://nemesis.lonestar.org/reference/telecom/modems/at/plain-at.html >> http://docs.kde.org/development/en/kdenetwork/kppp/appendix-hayes-commands.html >> >> Each one has links to further material. >> >> So you may want to add some more initialization commands before the dial >> command. Notably adjusting the S37 register, some N, V, and maybe W >> command; possibly starting with ATZ by itself. Of course you may wish to >> look at the results of some I commands as well. For controlling >> connection speed it should be done before the dial command. >> >> HTH > Attached are two text (capture) files of tests i have done; i >purposely used lower case so my commands via modem would stand out from >modem responses. > I have the USR CD and it gives the AT command set for their modem(s). > Other than the possibility of the Xn command, i see no way to set >data rate. > Please review those files and advise what i should try next. >** > Called "wonderful" "helpful" Qwest about connection problem. > The extensive phone line testing was done in Apr 2009 with complete >bill of health including almost no noise; that is when the tech said >that a stinger had (note tense) been installed. > The idiot at Qwest maintains there is no record of that, there is no >way to determine that, and that nobody there knows what i am talking >about (!!). > The very same idiot maintains that i can communicate at _any_ data >rate even above 1M (!!) and to call my ISP about the problem. Try setting S32 to 96.
From: Robert Baer on 30 Apr 2010 23:23 denali wrote: > On Apr 30, 12:28 pm, Robert Baer <robertb...(a)localnet.com> wrote: >> JosephKK wrote: >>> On Wed, 28 Apr 2010 16:45:04 -0700, Robert Baer <robertb...(a)localnet.com> >>> wrote: > (snip) >> ** >> Called "wonderful" "helpful" Qwest about connection problem. >> The extensive phone line testing was done in Apr 2009 with complete >> bill of health including almost no noise; that is when the tech said >> that a stinger had (note tense) been installed. >> The idiot at Qwest maintains there is no record of that, there is no >> way to determine that, and that nobody there knows what i am talking >> about (!!). >> The very same idiot maintains that i can communicate at _any_ data >> rate even above 1M (!!) and to call my ISP about the problem. >> > (snip) > > You're right, the person appears to be oblivious. There is a very > simple way for that phone answerer to obtain all the details of the > facility assigned to your phone line. It's called, appropriate > enough, the Line Assignment record. > > I can't call them about this for you, because I am not your designated > representative. If you have a way to conference me onto a call with > them, however, I can talk with them. But it might cost you a beer at > the nearest McMenamins. I presume you reviewed the two ascii files attached elsewhere; i made a third try with a differrnt setting S0=1, S32=2 and the modem indicated speed 45333/26400 with protocol LAPM/SREJ (whatever that means). So i went into dial-up networking and changed the initialization string for that. The little double-monitor icon now indicates 48K which is a decided improvement. Any way i can goose it more?
From: Robert Baer on 30 Apr 2010 23:28
JosephKK wrote: > On Fri, 30 Apr 2010 12:28:08 -0700, Robert Baer <robertbaer(a)localnet.com> > wrote: > >> JosephKK wrote: >>> On Wed, 28 Apr 2010 16:45:04 -0700, Robert Baer <robertbaer(a)localnet.com> >>> wrote: >>> >>>> Robert Baer wrote: >>>>> JosephKK wrote: >>>>>> On Tue, 27 Apr 2010 11:39:06 -0700, Robert Baer <robertbaer(a)localnet.com> >>>>>> wrote: >>>>>> >>>>>>> Martin Brown wrote: >>>>>>>> Robert Baer wrote: >>>>>>>>> Martin Brown wrote: >>>>>>>>>> denali wrote: >>>>>>>>>>> FYI, RE: JB's post.. leased line parameters are in no way applicable >>>>>>>>>>> to switched services. Forget about 3002 channels, etc. >>>>>>>>>>> >>>>>>>>>>> Since you had better data service that has become degraded, >>>>>>>>>>> something >>>>>>>>>>> is clearly wrong somewhere. >>>>>>>>>> Not wrong. Different. He should force a V34+ connection and see if >>>>>>>>>> that behaves any better - but he doesn't listen to advice. >>>>>>>>>> >>>>>>>>>> Most likely one of his neighbours has moved to ADSL and the >>>>>>>>>> engineers have pinched his real copper circuit for that. >>>>>>>>>> Multiplexed local lines do not carry 56k signals at all well. The >>>>>>>>>> older analogue technology modems are a bit more robust in that >>>>>>>>>> environment. >>>>>>>>>> >>>>>>>>>> Regards, >>>>>>>>>> Martin Brown >>>>>>>>> Well,now if i KNEW how to force V34+ i would try. >>>>>>>> You should pay more attention to the postings in this thread and >>>>>>>> also ask on comp.modems and/or us.telecom or whatever it is called. >>>>>>>> They will know where you can dial into for a DIY line bandwidth >>>>>>>> test. Assuming that end users are allowed to do such things in "the >>>>>>>> land of the free". >>>>>>>> >>>>>>>> You might find a prehistoric early 56k UK FAQ helpful in trying to >>>>>>>> configure your modem to work retro style. >>>>>>>> >>>>>>>> http://www.pierrot.demon.co.uk/faq/dtm.faq >>>>>>>> >>>>>>>> (it is well out of date and UK based but still has good hints) >>>>>>>> >>>>>>>> Regards, >>>>>>>> Martin Brown >>>>>>> I have that UK reference and it is interesting and a bit informative. >>>>>>> I have TerraTerm Pro but i cannot use it with my ISP to do any >>>>>>> testing. >>>>>>> If i ATDTetc in, that works and see the prompt for username but +++ >>>>>>> does not escape to modem; if i am online like now, TerraTerm barfs. >>>>>>> So _that_ type of testing is out unless there is another number or >>>>>>> alternate to try. >>>>>>> One of the suggested tests was with >>>>>>> http://www.whichvoip.com/voip/speed_test/ppspeed.html and jitter was >>>>>>> 610mSec, packet loss of 0%, MOS score (whatever that is) of 2.9, >>>>>>> download speed 26.2K, upload speed of 21.5k and QOS at 92%. >>>>>>> Measured loop current 35mA, different US Robotics modem acts the same. >>>>>> OK. It seems that TerraTerm Pro is part of the problem. XP comes with >>>>>> a properly primitive terminal program though. You might try that. >>>>> Do not use XP, but maybe a similar prog is available with Win98SE; >>>>> will look for it. >>>>> Thanks. >>>> Found HyperTerm for Win98SE, it seemed to be installed but did not work. >>>> So..uninstall, reboot, install and it works.. >>>> .. sort-of. >>>> ATDT972-231-0633 >>>> (wait a bit) >>>> +++ >>>> AT%L%Q >>>> ERROR >>>> AT&V1 >>>> ERROR >>>> AT&L >>>> ERROR >>>> ATO >>>> (am now back online with isp asking for username and password) >>>> So, STILL cannot get info! >>>> What next? >>> OK i started here: >>> >>> Google: "at command set" Which finds many things with these being on the >>> first page >>> >>> http://en.wikipedia.org/wiki/Hayes_command_set >>> http://nemesis.lonestar.org/reference/telecom/modems/at/plain-at.html >>> http://docs.kde.org/development/en/kdenetwork/kppp/appendix-hayes-commands.html >>> >>> Each one has links to further material. >>> >>> So you may want to add some more initialization commands before the dial >>> command. Notably adjusting the S37 register, some N, V, and maybe W >>> command; possibly starting with ATZ by itself. Of course you may wish to >>> look at the results of some I commands as well. For controlling >>> connection speed it should be done before the dial command. >>> >>> HTH >> Attached are two text (capture) files of tests i have done; i >> purposely used lower case so my commands via modem would stand out from >> modem responses. >> I have the USR CD and it gives the AT command set for their modem(s). >> Other than the possibility of the Xn command, i see no way to set >> data rate. >> Please review those files and advise what i should try next. >> ** >> Called "wonderful" "helpful" Qwest about connection problem. >> The extensive phone line testing was done in Apr 2009 with complete >> bill of health including almost no noise; that is when the tech said >> that a stinger had (note tense) been installed. >> The idiot at Qwest maintains there is no record of that, there is no >> way to determine that, and that nobody there knows what i am talking >> about (!!). >> The very same idiot maintains that i can communicate at _any_ data >> rate even above 1M (!!) and to call my ISP about the problem. > > Try setting S32 to 96. OK; that is a bit different than S32=98 where i have been having trouble since the "stinger" and also different than S32=2 which seems to give me 48K, a decided improvement. Will let you know what that change does. |