3Com 3C13886 - Router OC-3 ATM SML Flexible Interface Card Installation Manual page 132

3Com Router Module Guide
Chapter 4
As shown in the following two figures, both cables look similar except that the 75-ohm
4E1 adapter cable uses eight coaxial cables but the 120-ohm 4E1 adapter cable uses
four twisted-pair cables.
Figure 4-23 120-ohm 4E1 adapter cable
Figure 4-24 75-ohm 4E1 adapter cable
Note:
Both 75-ohm 4E1 and 120-ohm 4E1 adapter cables are required for ROUTER 4-PORT CE1/PRI FIC.
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