6 5
Modem Troubleshooting
Many problems result from a loose or defective cable, typing
errors, or a misunderstanding about how the modem should
work. First, ensure that the cable is connected properly. Second,
refer to the section in this manual that describes the task you are
trying to perform. Reread it to confirm that you are following
proper procedures, and try again. This clears up many problems.
Third, refer to the following for possible solutions to common,
easily-fixed problems.
Using a Modem Pool
Many cellular providers enhance their data service by providing
data modem pools. A modem pool is a group of modems the
cellular provider maintains to assist in translating data protocols
between modems. Placing your calls through a modem pool
will help you reach maximum cellular transmission rates. (The
maximum rate is 14.4 KBPS; however, a typical real-world rate
is 9600 BPS.)
If your cellular provider supports a modem pool, you may access
it by entering the prefix “*DATA (*3282) before the telephone
number you are calling.
For example, enter:
ATDT”*32825551212
The modem does not respond
to commands.
The modem does not answer.
The modem does not dial.
The modem cannot make a
connection.
The modem connects, but
cannot pass data.
Verify that the communications
software is set to use the COM
port assigned to the modem.
Confirm the modem is in auto-
answer mode.
Restart the communications
software package.
Type ATS0=n (where n equals
the number of rings before call
pickup).
Check the phone line; make sure
it is properly connected to the
modem’s cable.
Verify that you are using an
analog phone line. The modem
does not work with digital or
PBX phone lines.
Restore factory settings by
typing AT&F.
Disable auto-retrain using
AT%G0.
Make sure that the
communications package flow
control setting is the same as the
modem’s setting (e.g., XON-
XOFF).
Disable auto-retrain using
AT%G0.
Using Modem with PBX Systems
The modem on your TransPort X
KE
will work on most PBX
systems found in hotels and offices. The X
KE
modem will work
without problems on analog PBX systems.
However, some PBX systems are digital and/or supply more
than 100mA of loop current to the modem. The X
KE
’s modem, as
with all analog modems, will NOT work on these systems. You
may, in fact, damage your modem when trying to use such a
system.
The X
KE
has protective logic that protects the modem against
damage when plugged into a digital line or a line that supplies
more than 100mA of loop current. The modem will also send a
message to the user informing them of the problem and will ask
the user to unplug the modem from the line.
It is recommended that you check with your office facility
manager about the availability of analog lines, and to check for
analog data ports when using a line in a hotel.
