Modems

• USR Sportsters have been tested by independent laboratories and found to be among the most highly rated modems in establishing (and maintaining) high speed connections with the largest numbers of other brands of equipment.

• USR Sportsters can be easily firmware up-graded. This enables UltraNet to stay up to date with changing (evolving) modem technologies.
  (All of our modems are equipped with the USR firmware release of June, 1995).

• When a modem is unable to connect reliably with UltraNet's modems, first, try to dial into a different POP, and then from a different location altogether, to confirm that poor telephone line conditions are not the cause of your problem.
  • Connect Speeds of less than 21.0 kbps for a 28.8 kbps modem, or less than 9.6 kbps for a 14.4 kbps modem almost always indicate poor telephone line conditions .

  • Modems negotiate the connection speed based on the results of a probe of line conditions and will not connect at a speed which will produce and excessive number of errors.
    

  • The more sophisticated modems will negotiate separate send and receive speeds depending on the path conditions and can re-negotiate during a connection if conditions change.

  • The less sophisticated modems will simply drop the connection if error rates become excessive.

  • Refer to John Navas' Modem FAQ, ("Why Don't I Always Get 28.8 kbps Connections with my 28.8 kbs Modem?")

• Our modems answer incoming calls in a "hunt sequence", so that, while it is possible for UltraNet to have a defective modem, you are most unlikely to connect to it in subsequent dialing attempts.

• Utranet identifies each individual modem (and port) upon connecting, with information provided underneath the "CONNECT" message in the Trumpet Winsock Screen.
  MPn Sn tells you the modem pool and port number of each connection for diagnostic purposes.
  

• If a modem that had been functioning satisfactorily suddenly stops working, question whether or not it had been connected to a telephone line during a recent electrical storm. Telephone equipment is suseptible to electrical surges that can enter on the phone lines as well as through the power source.
  We have experienced several damaged modems from this cause ourselves!

• When experiencing connection problems:
  Determine if your modem can be up-graded to the latest product specifications by refering to the Modem Manufacturer's Information Sources
  (Especially important if your modem is several months old!)

  NOTE, Global Village Owners:
  Always check for factory up-grades first, before further troubleshooting!

  • Up-graded soft or firmware will usually improve performance markedly.
    Some modem manufacturers have an exchange program for up-grades.

  • Note the importance of purchasing a modem that can be easily up-graded as modem technology advances. (The "Clone" modems are not usually up-gradable, which is a good reason to avoid purchasing them!)

  • Post a problem in the comp.dcom.modems news group if the modem has no factory support available.

Initialization Strings:

This does not seem to make much sense because most all of today's communications applications require:

• Reset to factory defaults. (&F)
• Carrier Detect. (&C1)
• Normal DTR. (&D2)
• Hardware flow control. (&K3,\Q3, or on some modems &H1)

All of the above features should be enabled by default on most of today's modems. The best results are usually obtained with the shortest string possible. In some cases the "Generic Hayes" initializaton command is all that is required. (ATZ0)
All command strings to a modem must be preceeded by the characters "AT", (no quotes), and are generally not case sensitive.
A modem init string that would force all of the above parameters "on" would look like this:

AT&F&C1&D2&K3

Strings that usually prove successful are simply the strings that most modem manufacturers provide to reset the modem to factory defaults which should, (but don't always), enable the features necessary for successful TCP/IP connections.

Many modems will allow you to view the current settings in a terminal session by typing: AT&V (or USR 28.8 Sportsters, ATI4). You can compare these to your manual to see what parameters are set.

• Two of these init strings worth trying are AT&F or AT&F1, (USRobotics), which may simply re-initialize the modem to the factory defaults and tend to produce good results in the cases where the ATZ0 register may have been written into by some third party communications application, (rendering the modem inoperative for TCP/IP).
  (AT&F1 is the only initialization required for most U.S. Robotics modems).

• If you have access to the specific manual for your modem, and are trying to resolve a problem, be sure that all of the above features are enabled, (or not disabled), as you work out an initialization string.

• If the modem is a "No-Brand" (I call them "cardboard" modems), that was included as a part of a clone package, and you have no manual, and ATZ0 doesn't work, try the AT&F and AT&F1 before resorting to longer strings.

• If you get an error message on the Trumpet Winsock screen during modem initialization, try the commands one at a time, (preceeded by "AT"), in the Manual Login mode to see which one(s) are producing the message. Then eliminate them from the string.

• If your modem cannot negotiate a successfull connection, try disabling the data compression features with the appropriate "AT" command for your specific modem. Some modems can become confused when trying to negotiate compatible compression schemes with more sophisticated equipment.
  Check the examples below.

• Dropped connections can sometimes be reduced, (or eliminated), by adding the following commands to the modem initialization string: S10=50 S25=10 S38=5 These settings tend to make the connection more tolerant of breaks in the DTR or telephone circuits.

• If you experience a case where the modem wants to answer the phone after disconnecting from UltraNet, add S0=0 to the init string. (A fax program may have written into the modem's ATZ0 configuration).

• Modems that don't want to hang up with the standard Trumpet Winsock, (bye.cmd), script can be forced to hang up by momentarily dropping DTR.
  Open the "bye.cmd" file, under Dialer + Edit Scripts on the Trumpet Winsock menu bar.
  Add the following lines to the top of the script:

  set dtr off
  sleep 1
  set dtr on
  

  If that doesn't work by itself, open the "login.cmd" file, under Dialer + Edit Scripts on the Trumpet Winsock menu bar and add &d2 to the modem initialization string.

Initialization Command Strings for most major modem models.
(The above link is not gospel, but may provide a good starting place if you do not have a manual for your specific modem and are experiencing connection problems.)

Examples of Using "Generic" Modem Init Strings to Solve Modem Problems
When you do not have access to the manufacture's documentation or cannot identify the modem.

Mac Specific Init Strings
Check the Mac specific initialization strings here for Mac PPP.
Note: Usually &D0 (zero, not oh), is recommended to be added to Mac init strings. (This setting causes the modem to ignore DTR and may make your Mac setup less apt to drop connections.)

Telephone Line Issues:

• Make an outgoing voice call on the line you are using to evaluate whether or not the line is quiet.

• Go to the US Robotics Web Site for the access number to the USR Bulletin Board System that can be used to evaluate your line quality.

• Dialing out through an office "switch", (which will be evidenced by the need to dial some character(s) to get an "outside" line), does not work well due to the bandwidth restrictions present in the switch. Even switches which are certified for data connections seem to reduce line bandwidth enough to cause speed reductions or connectivity problems.

• If there is a separate line available, try to connect to UltraNet on it or better yet, from a completely different location.

• I have found, that in trouble shooting connectivity issues in homes and offices, everything from fax machines plugged into the same line, (or the modem's phone jack), to a $4.00 Radio Shack phone connected to the line and lying in a closet in the house, can cause poor connectivity and reduced data speeds.
  For test purposes, disconnect all other devices on the modem line.

• Report the line to the telephone company as being unable to "fax". (They do not want to support data communications of over 9600 kbps!)
  In more than one instance of poor connectivity, I have requested new "pair" from the phone service supplier, or simply ordered a new line and finding it satisfactory, cancelled the old one.

• Telephone service personnel have the ability to test the frquency response, (bandwidth), of a line at the wall jack, but must be persuaded to do such testing. You may not want to pay to have them enter your home to do this, but at least insist on testing to the point of entry.

• Be sure to disable "Call-Waiting" by preceeding the telephone number being dialed with *70,

Recommended Reference Material:

• John Navas' Modem FAQ.
  Must reading!

• Albert Belle Isle's Pages
  Also must reading for anyone desiring a full understanding of TCP/IP modem communications.

• The U.S. Robotics Technical Site An excellent problem solving tool for all brands of modems.
  (This site lists a USR Bulletin Board you may call to analyze and report on your telephone line conditions!)

• The Malch Data Communtications FAQ. (Another good source of Windows communications tips, a little on the light side).

• UltraNet's Tech-Tip Archive (Contains many arcticles on high speed data communications).

• Go to the News Group, comp.dcom.modems, for the latest information on modems.
  Post a problem to see if you can get a response from someone in the group.

Direct Factory Help and Information:

• Go to the Boca Web Site

• Go to the Global Village Web Site.

• Go to the Hayes Web Site.
  (Hayes, and Practical Peripherals).

  Note: For PPI support, e-mail to: PPISupport@aol.com.

• Go to the Megahertz Web Site.

• Go to the Motorola Web Site.

• Go to the Multi-Tech Web Site.

• Go to the Rockwell International Web Site.
  (Many generic modems use Rockwell chipsets).

• Go to the Supra Web Site.

• Go to the U. S. Robotics Web Site.

• Go to the Zoom Web Site.

• Go to the ZyXel Web Site.

• Go to the Yahoo List of Modem Manufacturer's Web Sites.
  (If you didn't find what you needed above).

These sites all offer direct access to the latest technical information on their products.
Up dated software or firmware solves many connectivity problems.

These sites also offer direct E-Mail to their Product Support Departments.
Post a problem to see if you can get a direct response from the Manufacturer.

Notes:

• Motorola MicroCom Parallel Port Modems must have their software drivers installed and configured. Find the MicroCom icon in the Windows control panel and select an un-assigned serial port. (Use MSD to determine which serial ports are unused). Set the port in the Ultranet Account Configuration Utility or edit the change into the c:\internet\winsock\trumpwsk.ini file under the "slip-port=n" setting.

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