FRITZ!Box 5490 Service - Knowledge Base
Pin assignment of ports for telephony devices
The FRITZ!Box has various ports for connecting telephony devices to it. Here you will find the pin assignment of the FRITZ!Box ports so you can use your own cables, for example.
1 "FON S0" port on the FRITZ!Box
The cables of ISDN devices connected to the "FON S0" port on the FRITZ!Box must be assigned as follows:
Note:You can have a technician install an S0 interface connected to the "FON S0" port. The "FON S0" port is terminated (two 100 Ohm resistors are switched on the "FON S0" port in the FRITZ!Box).
Fig.: Pin assignment of the ISDN cable
2 RJ11 sockets of extensions "FON 1" and "FON 2"
The two middle pins 3 and 4 are assigned on the RJ11 sockets.
3 TAE sockets of extensions "FON 1" and "FON 2"
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