3com MSR 20-20 사용자 설명서

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C
HAPTER
 4: F
LEXIBLE
 I
NTERFACE
 C
ARDS
Interface Cable
The interface that the FIC-1AE3 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. Several cable length options are available.
Figure 228   E3/T3 cable
n
The FIC-1AE3 and the FIC-1AT3 use the same type of cables for connection, which 
are called E3/T3 cables in this manual.
Connecting the Interface
Cable
c
CAUTION: By design, the FIC-1AE3 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 
FIC-1AE3 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 
FIC-1AE3 and another end to the Tx port on another device.
Step 3: Check the behavior of the LINK LED on the FIC-1AE3 panel: OFF means 
fault occurs on the line and the signal is out of synchronization. Check the line 
status.
FIC-1AT3
Introduction
FIC-1AT3, the 1-port 44 Mbps ATM-T3 interface card, provides these functions:
Two ATM cell mapping modes: ADM and PLCP.
Scrambling in data transmission.
Line clock (when working as DTE interface) and internal clock (when working 
as DCE interface).
Table 130   LEDs on the FIC-1AE3 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.
BNC connector
SMB connector
BNC connector
SMB connector
BNC connector
SMB connector
BNC connector
SMB connector
BNC connector
SMB connector