FRITZ!Box 6490 Cable Service - Knowledge Base

FRITZ!Box 6490 Cable Service

Setting up an external fax in the FRITZ!Box

You can use a fax machine connected to an analog port or the "FON S0" port of your FRITZ!Box to send and receive faxes over the internet.

1 Enabling fax transmission with T.38

If you want to use an internet telephone number for faxing, then you must enable T.38 (fax over IP) for fax transmission in the FRITZ!Box. With T.38, a special network protocol is used for fax transmission instead of fax tones. As a result, transmission is significantly less susceptible to interference:

  1. Click "Telephony" in the FRITZ!Box user interface.
  2. Click "Telephone Numbers" in the "Telephony" menu.
  3. Click on the "Line Settings" tab. If the tab is not displayed, then your cable provider automatically configures the line settings during configuration. You cannot change these settings later. Your cable provider can provide you with information on the settings.
  4. Click on "Changing the Settings" in the "Telephony connection" section. If the section is not displayed, enable the Advanced View first.
  5. Enable the option "Fax transmission using T.38".
  6. Click "Apply" to save the settings.

2 Reconfiguring the fax machine

Set up the fax machine in the FRITZ!Box, even if it is connected to the FRITZ!Box via an ISDN PBX:

  1. Click "Telephony" in the FRITZ!Box user interface.
  2. Click "Telephony Devices" in the "Telephony" menu.
  3. If the fax machine is already displayed in the list of telephony devices, click the (Delete) button for the fax machine.
  4. Reconfigure the fax machine: Click the "Configure New Device" button and follow the instructions.
  5. If you cannot select the port the fax device is connected to when configuring it, then another telephony device has already been configured for the port. You must delete this device first.
  6. If the fax machine is connected to the "FON S0" port on the FRITZ!Box, during configuration you will be shown which telephone numbers to assign to the fax machine. If the fax machine is connected by means of an ISDN PBX, you must assign the telephone numbers to the port on the ISDN PBX that the fax machine is connected to.