AT&T definity 7444 User Manual page 10

2)
When used with  Conference-Ring 
8 available patterns. Use to distinguish your ring from that of other nearby
telephones.
When used with  Speaker-Reset Spkr 
3)
of the environment to provide optimal speakerphone performance. Use whenever
you move your telephone to a different location (even in the same room), when
the telephone is unplugged, or when there has been a power failure. When any of
these three things happen, the light on this button will flutter to notify you that
the sound level and quality needs to be reset.
Select Ring Allows you to select your own personalized ring from among 8
available ringing patterns. Use to distinguish your ring from that of other nearby
telephones.
Self-Test Activates the lights, ringer, and display of your telephone. Use when you
want to test their operation.
Send All Calls Temporarily sends all your calls to the extension of a person
designated to answer them when you cannot (perhaps a secretary, receptionist, or
AUDIX). Use when you will be away from your desk for awhile, or when you do not
want to be interrupted by calls.
Speaker In the listen-only mode, allows you to place calls or access other voice
features without lifting the handset (when the speaker is on). However, in order to
speak to the other party, you must use the handset (the speaker must be off). Use
with feature activities that require listening only, such as on-hook dialing, monitoring
calls on hold, and retrieving messages. Note: Your telephone has either the Speaker
(listen-only) or the Speakerphone function. Check with the System Manager to see
how your telephone is set.
Speakerphone Allows you to place and answer calls or access other voice features
without lifting the handset. When used with
performs a test of the surrounding acoustic environment by using a sequence of tones.
When the tones stop, your speakerphone has finished adjusting itself for optimal
performance. It is now ready for use. Use the built-in speakerphone anytime you
prefer hands-free communication, both speaking and listening or for group conference
situations. Note: Your telephone may be set for the Speaker (listen-only) rather than
the Speakerphone (listen and speak) feature. Check with the System Manager.
Terminal Busy Indication
(on-hook) status of specified telephone. Use this information when servicing calls for
another person. For example, if you are a secretary servicing your supervisor's calls,
use this feature to see whether your supervisor's extension is busy or idle.
Transfer Transfers a call from your telephone to another extension or outside
number. Use when your caller needs to speak further with someone else. Note: Calls
from an outside number to your telephone can be transferred only to an extension, not
to another outside number.
you can select your own personalized ring from among
the built-in speakerphone performs an acoustic test
 -Select ,
Provides a visual indication of the busy (off-hook) or idle
the built-in speakerphone
6