Modems 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 cases, 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 used 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)

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. Asign 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.

If you bought the fax/modem from eprabhat.com and the above checks do not solve your problems, please get touchbase with our techincal team or send in a question at cmp_bgl@vsnl.net.

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