FRITZ!Box 5490 Service - Knowledge Base

FRITZ!Box 5490 Service

Configuring a combination telephone/fax machine in FRITZ!Box

You can connect a combination telephone/fax machine to an analog port or the "FON S0" port on the FRITZ!Box and then use it to send faxes and make telephone calls.

Note:All instructions on configuration and settings given in this guide refer to the latest FRITZ!OS for the FRITZ!Box.

1 Configuring combination telephone/fax machine

Configure the combination telephone/fax machine as a fax machine in the FRITZ!Box:

  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.

2 Disabling fax transmission with T.38

  1. Click "Telephony" in the FRITZ!Box user interface.
  2. Click "Telephone Numbers" in the "Telephony" menu.
  3. Click on the "Line Settings" tab.
  4. Click on "Change connection settings" in the "Telephony connection" section.
  5. Disable the option "Fax transmission using T.38" in the "Voice Packets" section. If the section is not displayed, enable the Advanced View first.

    Note:The T.38 standard (Fax over IP) allows reliable fax transmission over the internet. However, when T.38 is enabled, you cannot use the combination device to conduct calls over the internet. When faxing over the internet without T.38, faxes may not be transmitted properly.

  6. Click "Apply" to save the settings.
    • If you cannot send faxes without T.38, reenable the option "Fax transmission using T.38". If you are then able to send faxes, either leave T.38 enabled and only use the combination device for faxing, or disable T.38 and only use the combination device for conducting calls.