DMS10 switch question
Russell Pagenkopf
[please bear with me, the switch question is at the bottom]
I've run into a really weird one and I'm hoping someone can help. First
some background. We're working with a small telco here that is providing
dialup access to their customers in their exchanges (2). Last week they
went through some major power problems (up, down, in, out, ...) and since
then they've acquired a really weird problem.
Equipment: Lvingston Portmaster/Router and USR Sportster 33.6 modems
Problem: Modems will no longer consistently connect at 28.8 (things
worked just fine before the power problem) and only some of the modems
will connect at 28.8, but all modems can connect at 14.4 or less. Trying
to connect at 28.8 produces a number of interesting results.
1) Modems will get partway through the negotiation phase and hangup.
2) Modems will get partway through the negotiation pahse and hang.
3) Modems will get partway through the negotiation phase, go silent and
then try to retrain and hangup.
4) Modems will get partway throught the negotiation phase, go silent and
then try to retrain go silent an hangup.
5) And perhaps the weirdest thing of all, the modems will get partway
through the negotiation phase and then make a solid sounding URR sound
(not as high pitched as the modems will go, but not as low pitched as the
modems will go either, kinda in between) that is *much* louder than
anything the modems normally make, continue negotiation and hangup.
Now I've tried every solution I can think of from swapping modems to
reprogramming everything to having them check voltage, resistance and
capcitance to swapping lines to changing cables. As near as I can tell
we've narrowed it down to the switch, and the only thing I can figure is
that something in the negotiation phase of the modems is freaking the
switch out (thus the funny sound described above).
Switch info: Northern Telcom DMS10 ver. 406.10
Anybody out there dealt with these switches? Anybody have any ideas? Or
am I barking up the wrong newsgroup here? :-)
TIA
rus
--
rus
Russ Pagenkopf (406) 542-0838 Internet Services Montana (ism.net)
Hardware and Business Manager Connecting the World to Montana
All questions can be answered thus. NO. YES. MAYBE. EH?
Mike Sandman
otherwise changed some equipment in the CO.
For full details on loop current, see the Loop Current Tech Bulletin
at:
under Tech Bulletins or Loop Current.
Good luck... Mike
ru...@optim.ism.net (Russell Pagenkopf) wrote:
>Howdy folks,
>TIA
>rus
>--
>rus
-----------------------------------------------------------
Mike Sandman 708-980-7710
E-mail: mi...@sandman.com
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