Modem Help

This guide will help to solve problems with your fax modem and is split into 3 main sections:

• Getting Fax2Send to talk to the modem
• Getting the modem to dial telephone numbers OK
• Sending the Fax
• Receiving faxes

Where does Fax2Send hold the settings for the modem?

The modem settings are stored in the configuration file /etc/fax2send/config. You can change the settings by editing the file with a text editor or with the configuration tool fax2config (Linux desktop only).

Getting Fax2Send to talk to the modem

What settings can I change to make it work?

• Device - make sure this matches the serial port to which you have attached the modem.
• LockFile - you may need to set this if another program such as mgetty uses the modem. For example, if Device=/dev/ttyS0 you could set LockFile=/var/lock/LCK..ttyS0.
• Init_String - you may need to include the modem specific command for the type of flow control selected.
• Flow_Control - the best choice here depends on a number of factors; the configuration of your modem, the cable used and the type of serial port. In general Hardware flow will work OK.

How can I test the connection to the modem?

Fax2Send comes with a simple command to test out your modem. The command reads the settings from the configuration file and tries to initialise the modem for use with Fax2Send.

/usr/lib/fax2send/interface/class2 -nfaxmodem -t

Getting the modem to dial telephone numbers OK

Dialling the telephone number is not usually a problem when a modem is connected directly to an outside line. Problems usually occur when a modem needs to dial through an internal telephone exchange. It may need to dial a number to get an outside line or it may not be able to hear a dialling tone.

What can I change to make it work?

• Predial - include the '0' to get an outside line or change from tone to pulse dialling.
• Init_String - for the No Dial Tone problem include the command X0 to make the modem blind dial.

The modem always returns the "No Dial Tone" error when I try and send a fax?

This might mean that the telephone line you are trying to use is dead, but it could be that your telephone exchange does not offer a dial tone. Try setting X0 as part of the Init_String and the modem will blind dial.

How can I use a Calling Card?

Use the Predial setting to dial your free phone number and enter the calling card ID. Separate the numbers with pauses. For example if the free phone number is 800123456789 and the key code for the calling card is 9876543421 then you could try Predial=800123456789,,,,9876543421,,,,. You may need to vary the number of pauses depending on the supplier of the calling card.

Getting an external line through an internal telephone exchange

You may need to alter the following in the Predial string:

• Most exchanges use tone dial but some may require pulse.
• You will usually need to include a number to get an outside line such as 0 or 9.
• You may need to pause the dialling or wait for another dial tone after dialling the number for an outside line.

Checking out the debug trace file

The interface to the fax modem traces its conversation with the modem in the file /var/spool/fax2send/log/faxmodem. Experienced users may find this file useful.

What other problems might there be?

If you cannot get the modem to dial a number it may be that the telephone line is dead. Try putting a normal handset on the line to see if it is working. Warning: if you are using a telephone extension cable you may find that a normal handset will work but a modem will not - due to signal loss on the cable.

Try to listen to the modem dialling the number. The Speaker Setting controls when the speaker is switched on.

Sending the Fax

Most fax modems will have some fax machines they will not talk to - no matter what you do. Always try sending to more than one type of fax machine.

What can I change?

• Scan_Time - altering the value can sometimes get a modem working!
• Speed - some modems prefer to transmit at 14400.
• Init_String - you may need to include the modem specific command for the type of flow control selected.
• Flow_Control - the best choice here depends on a number of factors; the configuration of your modem, the cable used and the type of serial port. In general Hardware flow will work OK.
• Accept_Low_Quality_Page - turn this on if the telephone line quality is poor.

Remote end answers but nothing is transmitted.

This usually means that the fax modem could not negotiate correctly with the remote fax machine. Try changing the Speed and Scan_Time.

Only part of the first page is transmitted

Not a common problem but could mean that the flow control is not working properly. Try changing the Init_String and Flow_Control settings.

Transmission always fails at the end of the first page

Quite a common problem that could be caused by:

• Flow Control. Try changing the Init_String and Flow_Control settings.
• Poor quality telephone lines. Try setting Accept_Low_Quality_Page.
• A problem in the original negotiation. Try changing the Speed and Scan_Time.

Transmission always fails somewhere after the first page

This is a very unusual problem and could be caused by the actual document being transmitted. If another document also fails after page 1 then try the changes made above.

Receiving a Fax

What settings can I change to make it work?

• Receive - set this parameter to yes.
• Rings - change the number of rings before the modem answers the call.
• Scan_Time - altering the value can sometimes get a modem working!
• Speed - some modems prefer to receive at 14400.
• Init_String - you may need to include the modem specific command for the type of flow control selected.
• Flow_Control - the best choice here depends on a number of factors; the configuration of your modem, the cable used and the type of serial port. In general Hardware flow will work OK.

Configuring to Receive Faxes

Set the Receive parameter to yes.

Sharing the modem with a fax machine

You can use a normal fax machine as a backup device for receiving faxes. For example, you could configure the fax machine to answer on the 8th ring and Fax2Send to answer on the 3rd ring. See Rings.

Setting the number of rings before answer

You can set the number of rings before Fax2Send answers a call with the Rings parameter.