Model 2830 - 10 Button 1A2 Multiline Phone Wiring Diagram
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BSP 503-701-101 ISSUE 9, Oct 1979 - Fig. 10 Sheets 1 and 2


Unknown source -- possibly older wiring diagram than above.
Note in this diagram (different from above), the "LG" terminals for all 9 lines
are wired together at terminal screws "R", "W", "W" (31, 28, 34, 37, 40, 43, 46, 49, and 48).
My own 2830 is wired this way.