AT&T Callmaster Series Reference Manual page 481

ISDN 7506 Display Terminal
Self-Test
The 7506 display terminal has a local self-test. When used with the SELECT button, the
DROP/TEST button begins and ends the self-test.
Loudspeaker
The 7506 display terminal has a built-in, programmable SPOKESMAN loudspeaker. The
SPEAKER button is used to turn the loudspeaker on and off. The volume arrow buttons control
the volume of the loudspeaker.
Speakerphone
The 7506 display terminal has a built-in, programmable speakerphone. The SPEAKER button is
used to turn the speakerphone on and off. The green light next to the SPEAKER button goes on
when the speakerphone is active. The volume arrow buttons control the volume of the speaker-
phone.
MUTE button
Pressing the MUTE button mutes the handset or the speakerphone, whichever is active. The red
light next to the MUTE button goes on. The user is placed in a listen-only mode.
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