AT&T Spirit Communications System - Manual (Page 7)

Ringing Patterns
Two short rings—call from outside system
One long ring—call from another intercom extension
One short, one long ring—transferred call
Three short rings—transfer return or line reserve callback
(or auto callback on a 2448 system)
One low-volume ring pattern—call when your telephone
is busy (or calls are forwarded on a 2448 system)
Groups (2448 System)
Telephones in 2448 systems are assigned to
groups according to their intercom extension
numbers.
Intercom Extension Numbers Group Number
10-17
18-25
26-33
34-41
42-49
50-57
61
62
63
64
65
66
Indicator Light Patterns
I USE (The telephone line you are
currently using)
Very Long On, Short Off, repeat
THEY USE (The telephone line
someone else
IS currently using)
Steady On
RINGING (A telephone line that is
ringing normally)
Long On, Long Off, repeat
CALLBACK SIGNAL (The system is
calling you for a line reserve callback
Short On, Short Off, repeat
or transfer return)
I HOLD (A telephone line that you One Short Flash, Very Long Off, repeat
have placed on HOLD)
THEY HOLD (A telephone line that
someone else has placed on HOLD)
Two Short Flashes, Very Long Off, repeat
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