The cables of ISDN devices connected to the "FON S0" socket on the FRITZ!Box must be assigned as follows:

Note:If you use the adapter included with delivery you can use both of the FRITZ!Box's "FON S0" sockets, without the adapter you can only use the first socket. You can have a technician install an S0 interface connected to the "FON S0" socket. The "FON S0" socket is terminated (two 100 Ohm resistors are switched on the "FON S0" socket in the FRITZ!Box).

Fig.: Assignment of the ISDN cable for first socket

Fig.: Assignment of the ISDN cable for second socket

The two middle pins 3 and 4 are assigned on the RJ11 sockets.

The TAE sockets are assigned in such a way that contacts 1 and 2 on TAE plugs must be assigned (see fig.).

Fig.: Contacts 1 and 2 on a TAE plug