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How do I install an ISDN modem ?

I recently bought an ISDN modem. Now, my question is how do I install it and how do I configure the DUN (Dial-Up Networking) to make it function correctly ?

The modem is a 3Com U.S. Robotics Sportser ISDN TA. (It is an ISA modem). TA stands for Terminal Adapter. The ISDN line has two phone numbers.

I tried to install the modem through the setup program, which goes well, but it installs the modem as a network adapter. The faxt is that I don't know anything about ISDN modems, so is this normal ? And if it is, how should I install the Dial-Up connection, because when I try to install a new connection, Windows 98 doesn't find the modem. When I try autodetect neither. And I can't choose it from the list. I tried "Have Disk", but there are no *.inf files on the disks, only *.cab and *.exe.
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1 Solution
Your ISP must offer ISDN-support, or else your modem will not be able to connect to the ISP.  So, ask your ISP for instructions.  If they *WANT* your business, they will have instructions.  If they cannot supply instructions, switch to a different ISP.

> it installs the modem as a network adapter ... is this normal ?

Surprisingly, the answer is "yes".

My digital-camera connects as a "removable hard-drive", rather than as a "camera".  So, expect to be surprised.  :-)
ZerquishAuthor Commented:
Adjusted points to 475
ZerquishAuthor Commented:
The ISP supports ISDN, and that's for sure, because I work there. I asked everyone I know about the problem, but no-one can help me...

My problem is that it installs it as netwok adapter. So you tell me that's normal. OK then, but how do I get it working correctly ? How do I make it dial ?
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ZerquishAuthor Commented:
I mean I am 100% sure that the ISP supports ISDN, not that it supports it because I work there. ;)
Try "the ISDN Watering Hole"

I've looked at it, in the past, but, as I write, it's not accessible; I hope that it's still online.
GO TO: http://consumer.3com.com/sportster128k/filelibrary/index.html

How to order ISDN service (MS Word document)

Ordering ISDN Service
This chapter gives you and your local telephone company all the information needed to set up the lines correctly.
To order ISDN service, contact your local telephone company, give them information about your I-modem, and record information that they give you, such as your new ISDN telephone numbers, called SPIDs.
Call the U. S. Robotics I-team at (888) USR-ISDN to do the installation.
  The U.S. Robotics I-team
The I-team is a subset of U.S. Robotics’ Customer Support department that provides assistance with the ISDN ordering and configuring process.  The I-team determines the availability and pricing of ISDN service in your area, installation costs, lead time for installation, and will coordinate the configuration of the telephone company’s equipment so your I-modem will work properly.
   Requesting ISDN Service
1      Call your local telephone company and request Bellcore Capability Package S (listed in Bellcore SR-3840).
      If your telephone company does not recognize Bellcore capability packages, request the following items:
· ISDN BRI service.
· Number of channels:  2B+D, with no packet-mode data on the D-channel.
· Call type support:
This channel      Supports
Data B-channel      Circuit-Switched Voice and Data (CSV/D)
Analog Device B-channel      Circuit-Switched Voice and Data (CSV/D)
· Dynamic TEI assignment.
· Multipoint bus configuration.
· No features or special services such as CACH EKTS, call forwarding, or hunt groups.
· Terminal Type A.
· RJ45 jack (RJ11 is acceptable).
2      Specify your preferred long-distance provider.
3      Ask the telephone company which type of central-office switch your ISDN line will terminate and which protocol the switch uses. Record the switch type and protocol here:
ü      Switch      Protocol
r      AT&T 5ESS      Custom
r      AT&T 5ESS      National ISDN-1
r      Northern Telecom DMS-100      Custom (PVC 0 or 1)
r      Northern Telecom DMS-100      National ISDN-1 (PVC 2)
r      Siemens EWSD      National ISDN-1
r      Other      National ISDN-1
 4      Obtain the following information from your local telephone company:
· 1 SPID (Service Profile Identifier) per B-channel.
· 1 DN (Directory Number) per B-channel.
· Call types supported on each B-channel.
· If the switch does not auto-assign TEIs (most do), then you need one fixed TEI per B-channel.
For this      Record the number here
SPID 1      
SPID 2      
DN 1      
DN 2      
5      If you have an internal I-modem, continue with Chapter 4, Installing the Internal I-modem.
      If you have an external I-modem, continue with Chapter 5, Installing the External I-modem.
ran1 Comment # 2:
Based on your limited experience in this area I suggest you call the US Robotics Installation team first. Call Robotics I-team  (888) USR-ISDN to assist with the installation. They will coordinate with your local telco.

Download this file: How to order ISDN service (MS Word document) Similar to above comment.

Confirm that you have the latest driver.

Download manual if required.

Have all information available on your computer, modem, part # on box, etc.


It is common for the US Robotics TA to load as an Adaptor especially if it is the Sportster model. Once you have loaded it as an adaptor and configured the software that comes with it it should link up and you should be all set. A side note even though it loads as an adaptor it will still show up in DUN you may have two options that appear that may read like Sportster 128 dial up 0 and Dial up 1 or USR dial up 0 and 1 this is for 1 channel (0) and 2 channels would be (1).

Let me know if I can help anymore

ZerquishAuthor Commented:
This question has a deletion request Pending
This question no longer is pending deletion
> This question is pending deletion. If you object,

I do.  You seem to have obtained valid information.  If not, please indicate what further information you need.
I would agree. It is nice to hear what the solution actually was and that the modem is working and / or the reason for the deletion. sometimes the imformation is helpful in helping others.

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