AT&T System 25 - Manual (Page 21)

Paging
If your company has a paging system, you may access the
system by dialing a code. See your System Administrator for
the Paging access code and for additional information if you
have paging zones.
Using the
1 Listen for
2 Make the
3 Hang up.
Paging System
dial tone, then dial the Paging access code.
announcement.
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