AT&T System 75 Wiring Diagram page 230

Installing DS1 Tie Trunks
DS1 tie trunks provide a 1.544 Mbps digital data service between two
colocated System 75 or 75 XEs or between the system and a data
network using T1 carrier facilities. The TN722 DS1 tie trunk circuit pack
(R1V2/V3) provides connection capability to the DS1 facility for 24
independent trunks. Table 3-H shows the lead designations for the DS1
circuit pack.
The following connector cables are available to connect the DS1 tie
trunk circuit pack to DS1 digital facilities:
C6C connector cable (comcode 104 307 327)—50-foot long
shielded cable equipped with a 50-pin male connector on one end
and a 15-pin male connector on the other end. Use this cable to
connect a DS1 tie trunk circuit pack to a 551-type Channel Service
Unit (CSU).
C6D connector cable (comcode 104 307 376)—50-foot long
shielded cable equipped with 50-pin male connectors on each
end. Use this cable to connect DS1 tie trunks in colocated System
75 or 75 XEs.
C6E connector cable (comcode 104 307 434)—100-foot long
shielded cable equipped with a 50-pin male connector on one end
and a 50-pin female connector on the other end. Use this cable as
an "extension" cable between the DS1 tie trunk circuit pack and
the other connector cables.
C6F connector cable (comcode 104 307 475)—50-foot long
shielded cable equipped with a 50-pin male connector on one end
and a three inch stub on the other end. This cable is used to
connect the DS1 tie trunk circuit pack to channel multiplexers
requiring hardwired connections.
Miscellaneous Wiring Installation
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