TX 4000 PCI SS7 Network Interface Board Installation Manual Establishing network connections
Testing in loopback mode You can connect the board in loopback mode to test the digital trunk application
without connecting to the telephone network. The following illustration shows the
loopback configuration that connects trunk 1 and trunk 2 with crossover cable on a
TX 4000 board:
1
2
4
5
1
2
4
5
Wiring diagram of crossover cable
Trunks 1 and 3
Trunks 2 and 4
Crossover cable
The crossover cable connects the transmit signals from one trunk to the receive
signals on another trunk by connecting the pins as shown.
If your board configuration uses two optional trunk adapter cables to access trunks 3
and 4, you can connect the adapter cables in loopback mode. Use the crossover
cable to connect the transmit signals on one of the adapter cables to the receive
signals on the second adapter cable as shown in the following illustration:
Trunks 1 and 3
Trunks 2 and 4
Ethernet 2
Ethernet 1
TX 4000 board
Dual T1/E1 120 ohm
adapter cables
Shielded RJ-45 cables
Dialogic Corporation 33