To the knowledge base

Conducting internal calls

If several telephones are connected to your FRITZ!Box, you can conduct (free) internal calls between the telephones. For example, you can use a cordless telephone to call a telephone connected to an analog extension of the FRITZ!Box.

If you have configured an additional FRITZ!Box for telephony in the Mesh, you can also make internal calls between telephones on the Mesh Master and on the Mesh Repeater.

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

1 Preparations

Telephones that are connected to the "FON S0" socket on the FRITZ!Box either directly or via an ISDN telephone system (PBX) cannot automatically be reached internally. Although the FRITZ!Box assigns an internal number to the telephones during setup, this telephone number must still be assigned in the telephone or the telephone system:

Configuring a telephone in the FRITZ!Box

  1. Click "Telephony" in the FRITZ!Box user interface.
  2. Click "Telephony Devices" in the "Telephony" menu.
  3. Configure all of the telephones connected to the "FON S0" socket as ISDN telephones. To do so, click the "Configure New Device" button and follow the instructions.
  4. If you connected an ISDN telephone system to the FRITZ!Box, also configure all of the analog telephones connected to this telephone system as ISDN telephones in the FRITZ!Box. To do so, click the "Configure New Device" button and follow the instructions.

Assigning an internal number in the FRITZ!Box

  1. Click "Telephony" in the FRITZ!Box user interface.
  2. Click "Telephony Devices" in the "Telephony" menu.
  3. Click the (Edit) button for the relevant ISDN telephone.
  4. Select the internal number, for example 52, from the drop-down list "Number of the terminal device".
  5. Click "Apply" to save the settings.

Assigning an internal number in a telephone

  1. Assign the internal number to the ISDN telephone as the incoming telephone number. If the telephone is connected to a telephone system, assign the telephone number to the extension of the telephone system instead of to the telephone.

2 Conducting internal calls

Configuring a telephone to use the keypad function

Keypad sequences are strings of characters and numbers that you can use to enable or disable functions. You can use keypad sequences immediately with telephones, such as FRITZ!Fon C5, that are registered with the base station of your FRITZ!Box. If you want to use them with a telephone connected to the "FON S0" port or a cordless telephone that is not registered with the FRITZ!Box's base station, you must enable the keypad function first:

  1. Configure the telephone so you can send keypad sequences (sequences of characters and numbers, such as *121#) and enter special characters such as * and # with it. On many telephones, you can configure this function in the menu "Operation at a PBX > Dialing options > Dial * and #".

Making internal calls

  1. If you want all of the telephones connected to the FRITZ!Box to ring, enter **9 to make a broadcast call. You then conduct the call with the party who answers the telephone first.
    • If you want several telephones connected to the FRITZ!Box (call group) to ring, enter ** followed by the quick-dial number of an internal call group, for example 701. You then conduct the call with the party who answers the telephone first.
    • If you want a specific telephone to ring, enter ** followed by the internal number of the telephone. You can also use the "INT" key on a FRITZ!Fon.

      Example:
      To transfer the call to the first cordless telephone, enter **610.

      Note:You can find the internal numbers of the telephony devices in the FRITZ!Box user interface under "Telephone Book > Internal Numbers".