FAQ
True Telco related problems should be related to constant disconnections or the lack of a connection. See the section on Connection Speeds if you are getting a lower than expected connection speed. See the section related to your modem and software for information on how to obtain other important troubleshooting information.
The phone network was designed for voice not data communications. Modems are designed to use this network for exchanging data. The latest modem technologies push the upper limits of quality phone lines. Modem connections at 14.4 and higher are unreliable without Error Correction (error correction lowers and increases your baud rate based on current line conditions). A connection speed does not necessarily reflect the current connection speed as this fluctuates. The connection speed is not necessarily a sign of performance. It is an academic issue because the throughput (the speed in which you are downloading data) is what matters the most. See the below paragraphs for V.34 and 56k.
V.34 modems (i.e. 28800 or 33600) enhanced Error Correction protocols and pushed the limits of analog phone lines to their limit (obtain the V.34 guide for more information). 33600 is a theoretical limit and is rarely seen. If you are getting a connection speed of 26400 or higher, consider yourself lucky because one of the most common connection speeds is 24000 (if you consistently see 19,200 and lower connection speeds you may want to go through the troubleshooting in this guide).
56K modems take advantage of the "mostly" upgraded digital phone network. The call route between your home and the ISP must have only ONE Analog to Digital conversion (this is not guaranteed as voice lines do not require this- obtain the x2 guide for more information). The highest theoretical connection speed using 56K is 53333 (the FCC regulated limit). The actual connection speed will fluctuate. You may obtain a V.34 (i.e 28800 connection) if there is more than one Analog to Digital conversion. If the call route has only one Analog to Digital conversion you will obtain an x2 connection which may range from 33333 to 53333. This connection speed varies because there is an Analog portion of a 56K connection.
As mentioned in the connection speed section, error correction was developed to resolve performance problems with modem connections. Without error correction your modem would never connect or frequently disconnect. Error correction allows the modem speed to lower or increase based on current line conditions. It should be performed by the modem itself (hardware error correction). This means the modem has the built in software to perform error correction. Software error correcting modems require your computer to perform the error correction. Since this process is slow these modems do not perform well (our service does not support these modems). Since error correction protocols are changed and updated often most hardware error correcting modems offer Firmware updates (which upgrades the error correction- obtain the modem help guide for more information).
If any of the three are unreliable your connection will be affected. Verify you have the help guide for your software package to rule out software problems. Retrieve the Modem Help Guide for modem related issues and have your phone lines checked. Remember a low connection speed of 24000 with a 33600 modem is normal (retrieve the V.34 guide for more information). Also be aware x2 is not guaranteed (retrieve the x2 guide for more information).
Note: This checks for noise between your home and first Central Office.
If you have any connection problems it may be related to "Line Noise" from your phone line. In order to really listen to your phone line you need to get rid of the dial tone. Lift up the phone handset and dial any number valid for your location (i.e. in the U.S. try dialing a 1). Once the dial tone is gone you have about 30 seconds to really listen to your phone line (after about 30s the line may change to a busy signal). Listen closely to the line and verify you do not hear any pops, bangs, crackles, creaking or faint voices in the background. Any of these noises can cause your modem connection to fail.
These noises can be caused by something simple. Maybe a loose screw on a connector block somewhere between you and the exchange or water in one of the Telco cable ducts where the water-proofing (around the cable joints) has started to break down. It could also be a bad connection in the house somewhere and not necessarily on the line extension that is feeding your modem. Voices (or crosstalk) are not so easy to find and are usually more likely to be further into the system. The noises can also be coming from your phone or external wiring. So plug another phone directly into the wall jack and repeat the procedures above.
Cordless phone jacks and extra "outside wiring" near the phone jack should be removed. If you have a double phone jack on the wall try disconnecting the other phone line. All of these items may cause interference and connection problems.
To use your modem to run phone line diagnostics you need to first find what type of modem you are using. Most modem manufacturers use the Rockwell chipset, except a few like U.S. Robotics (USR) modems which use their own chipset (Megahertz uses the USR chipset). To find out what chipset your modem uses you can contact your manufacturer or use a "Terminal Mode" to find if your modem has a Rockwell chipset. Put your modem into a Terminal Modem (see the below help for information) and send the following command: AT&V and hit enter. With Rockwell you should see a complete configuration dump starting with "Active Profile" and ending with "Telephone Number Stores." Next send the command ATI4 and you should see up to 4 rows of checksum digits in "hex."
If you have a Rockwell chipset follow the below procedures:
These two figures are the Line Level (%L) in -dbm (-20dbm in the example above) and the Eye Quality Monitor (%Q) index (8 in the example above). The two figures of -20dbm and 8 are reasonable values and higher figures mean worse connections. A value of -24dbm and higher on the first may mean a bad connection or no connection at all (note that "higher" refers to the actual number and not its relative negative value). A value of 15 and higher on the second mean there are real line problems with your Telco circuit. You will need to contact your Telco if you have bad figures.
If you are using a USR based modem chances are you can use ATI6 for checking. This procedure can be done on-line as listed in the Rockwell process or off-line since the USR chipset "remembers" the last connection. To perform this test off-line connect to the Internet for as long as possible and preferably after a disconnection go into a terminal modem (without dialing in). Type ATI6 and hit enter. The ATI6 will provided a full listing of modem connection information. The part you are interested in is the Blers or "Bit Link Error RateS". Ideally this figure should be 0, but if you have been on awhile and see this figure as 1 or 2 you probably have nothing to worry about. If it climbs much higher then you are probably suffering from noise or low level or both (as in the Rockwell example above). Unfortunately USR modems do not give an indication of the actual received carrier level in decibels/milliwat (dbm).
If your modem does not have a USR or Rockwell chipset consult your modem manual for diagnostic information or contact the manufacturer directly for information.
Start Hyper Terminal from Windows Accessories (it can be installed from Add/Remove Programs in Control Panel). Once there start any existing icon (or create a new connection icon) and click Cancel on the Connect box. The only necessary setting is choosing the correct modem. From this panel you can send commands to your modem by typing into the "white screen."
Start Terminal from the Accessories Program group. Once within Terminal click Settings from the menu bar and then Communications. Verify your com port is properly selected in the Connector field and click OK. From this panel you can send commands to your modem by typing into the "white screen."
Be ready to advise them that you have Line Noise and/or Low Line Level. Explain to them you are using a modem (do not hide this) and tell them normal voice communications is fine. If you do not tell them you are using a modem they will run a "quick" test and say the line is fine. This is not an accurate test, it is always best to have someone come on-site. If possible ask for a Data or "Fax" specialist. Ask if your digital exchange has a setting to have AGC (Automatic Gain Control) turned off and your line setting at the exchange set to position 5. Also ask the phone company to perform a trace from your home to our equipment (trace the call from your home to our local access number). Have them check the signal strength and quality through each Central Office. It may take several visits to locate the true source of the problem especially when Line Noise is present.