AT&T 75 Wiring Manual page 519

NOTE: FOR DISTANCES OVER 50 FEET (15.2 M)
Figure 4-60. Connections for DS1 Tie Trunks Between 2 System 75s or System
75 XEs
NOTE: FOR DISTANCES OVER 50 FEET (15.2 M)
USE C6E CONNECTOR CABLE(S) BETWEEN
C6C CONNECTOR CABLE AND DS1 TIE TRUNK
CIRCUIT PACK.
Figure 4-61. Connections for DS1 Tie Trunks Using 551 T1 CSU
USE C6E CONNECTOR CABLE(S) BETWEEN
C6D CONNECTOR CABLE AND DS1 TIE TRUNK
CIRCUIT PACK.
66-TYPE HARDWARE
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