FRITZ!Box 7390 Service - Knowledge Base

FRITZ!Box 7390 Service

Maximum cable lengths

The FRITZ!Box comes with various cables to connect it to your line, a computer, or hub, for example. If a cable is too short, you can extend or replace it. Since you can only extend cables to a certain limit, below you will find information on the maximum possible length for each type of cable.

1 DSL/telephone cable (Y cable)

Important:You can only extend the short ends of the DSL/telephone cable that lead to the DSL and landline. Signal interference may occur if the common DSL/telephone part of the cable is extended.

The following maximum lengths are possible:

  • A maximum of 10 meters between the FRITZ!Box and ISDN-NT.

    Note:If the ISDN-NT is too far away, you can have a technician install an S0 bus that you can connect the ISDN-NT to.

  • A maximum of 100 meters between the FRITZ!Box and analog landline.
  • Up to 20 meters between the FRITZ!Box and DSL line; many DSL lines allow even more.

    Note:If you are making your own DSL cable, we recommend using CAT 5 UTP network cables.

2 Telephone cable

The cable between a telephony device and an analog extension on the FRITZ!Box (for example "FON 1") may normally be up to 100 meters long, but it depends on the telephony device used.

The cable between a telephony device and the "FON S0" port on the FRITZ!Box may be up to 10 meters in length.

Note:You can also have a technician install an S0 bus which is connected to the "FON S0" port. It is important for the ISDN port "FON S0" on the FRITZ!Box to be terminated. Two 100 Ohm resistors are switched on port "FON S0" in the FRITZ!Box.

3 Network cable

The network cable between the FRITZ!Box and a computer or hub/switch may be up to 100 meters in length.

4 USB cable

The cable of USB devices connected to the USB port on the FRITZ!Box should not exceed 5 meters.