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Hardware Troubleshooting Guide
Fax/Modem Troubleshooting Tips
My modem is a 56K, but I can connect to the Internet only at
slower speed.
The current copper wired telephone lines are limited only to
about 53K. If you are connected only to 33.6 or 28.8K, check
the following first:
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Is
your modem compatible with the modem used at your ISP?
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Is
your modem set up to run at full speed?
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What's the maximum speed your ISP allows?
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How
far away are you from your ISP?
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Some
modems need special initiation strings to get full speed.
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Some
conditions are out of your control, such as weather and
conditions of the telephone lines in your community.
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Problems may occur when you are dialing through a phone
system such as one in a hotel.
Modem answers incoming calls and then returns to the on-hook
condition, disconnecting the caller:
This occurs most often when connecting to a UNIX system. In
most case, the host does not prefer to see any result or
command echo codes. If this is the case, the codes can be
disabled by adding E0 Q1 to the modem configuration string.
The modem dials and appears to complete the connection,
but the communications software does not enter the correct
mode. (The screen remains blank)
This is normally caused by an I/O address or IRQ conflict.
Verify that the COM port is not in use by any other serial
device and if necessary use another COM port or I/O address
setting. Refer to your computer manual on how to determine
what serial ports are installed.
The modem dials and appears to complete the connection,
but the communications software does not enter the correct
mode. (The screen remains blank)
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There may be an I/O conflict (see the solution for the
previous problem).
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The
Result Codes may have been disabled by the software
configuration set up. Check if Q1 is in the configuration
or initialization string. If so, change it to Q0.
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Your
software may require numeric result codes rather than
verbal result codes. Use either V0 for numeric result
codes or V1 for verbal result codes in your initiazation
or configuration string.
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Some
software require full extended result codes (i.e., CONNECT
33600 instead of CONNECT). This can be controlled by the
Xn command. X0 sends a summarized code (CONNECT) and X4
sends a full extended code (CONNECT 33600)
The modem does not auto answer
The auto answer mode is determined by the S0 register. If S0
has been set to 0, the modem will not answer. Assign another
value to S0 by entering the following command: S0=n, where n
= the number of rings to occur before the call is answered
(ATS0=2, the modem answers after two rings)
The modem always answers the phone.
Set the S0 register to 0. ATS0=0.
The communications software displays, "No Dial tone."
Make sure that your phone cable is working properly and that
it is firmly seated to the phone socket at your phone jack
and in the real panel of the modem.
A high pitched squeal is emitted from the external
speakers
This phenomenon is "feedback" and occurs when the microphone
is pointed at the external speaker or is close enough to
pick up the speaker output. This may be remedied by using a
unidirectional microphone, making sure that it is pointed
away and as far from the speaker as functionally possible.
Another option is to use a headset with an attached
microphone.
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