3Com 3C13886 - Router OC-3 ATM SML Flexible Interface Card Installation Manual page 80

3Com Router Module Guide
Chapter 3 Multifunctional Interface Modules
Figure 3-42 120-ohm 4-port module conversion cable
Figure 3-43 75-ohm 4-port module conversion cable
Caution:
Both 75-ohm 4-port module 1 and 120-ohm 4-port module conversion cables are required for 4-port
module modules, while E1 cable is optional, so you need to order E1 cables when purchasing a 4-port
module module. Otherwise, they will not be provided.
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