3Com Router Module Guide
Chapter 4
4-37
Table 4-22
LEDs on the ROUTER 1-PORT T3 ATM FIC panel
LED
Description
LINK
OFF means no link is present; ON means a link is present.
ACT
OFF means no data is being transmitted or received; blinking means data is
being received or/and transmitted.
4.9.4 Interface Cable
The interface that the ROUTER 1-PORT T3 ATM FIC provides uses two SMB sockets
for data transmitting and receiving respectively. The ports adopt the 75-ohm
unbalanced transmission mode and are connected to the peer device using a pair of
75-ohm unbalanced coaxial cables as shown in Figure 4-34. Several cable length
options are available.
Note:
The ROUTER 1-PORT T3 ATM FIC and 8.8 ROUTER 1-PORT E3 ATM FIC cards use the same type
of cables for connection, which are called E3/T3 cables in this manual.
4.9.5 Connecting the Interface Cable
Caution:
By design, the ROUTER 1-PORT T3 ATM FIC is protected against lightning strikes. But when outdoor
cabling is involved, you are recommended to add a special lightning arrester at the input end of the
E3/T3 cable for better protection.
Step 1: Connect the SMB connector of an E3/T3 cable to the Tx port on the ROUTER
1-PORT T3 ATM FIC and another end to the Rx port on another device.
Step 2: Connect the SMB connector of another E3/T3 cable to the Rx port on the
ROUTER 1-PORT T3 ATM FIC and another end to the Tx port on another device.
Step 3: Check the behavior of the LINK LED on the ROUTER 1-PORT T3 ATM FIC
panel: OFF means fault occurs on the line and the signal is out of synchronization.
Check the line status.