AT&T System 75 Wiring Diagram page 225

CHAPTER 4. STATION WIRING
10.
Insert handset adapter on same side of handset bracket.
Note: The handset adapter is available in two models:
854A-03 (black) or 854A-143 (burgundy). A bracket is not
required for a headset.
11. Connect handset cord to jack on same side of console as handset
bracket.
12.
Administer console per AT&T 2System 75 and System 75
XE—lmplementation (555-200-651) and AT&T System 75 and System
75 XE—Administration (555-200-500).
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