AT&T System 85 Telephone User Manual


 
ISDN 8503T Voice Terminal
Note: The terminating resistor jumpers must be set
only
by qualified service personnel.
The terminating resistor jumpers must be set to OFF when the set is in a point-to-point
configuration and the terminating resistor is in the closet or a 440A4 is connected on the
line.
The terminating resistor jumpers must be set to ON when the set is in a point-to-point
configuration and the terminating resistor is
not
in the closet or a 440A4 is
not
connected
to the line.
The terminating resistor jumpers must be set to OFF when the set is in a multipoint confi-
guration and the terminating resistor is in the closet, a 440A4 is connected on the line, or
the jumper is set to ON in one of the other sets on the line.
The terminating resistor jumpers must be set to ON when the set is in a multipoint confi-
guration and the terminating resistor is
not
in the closet, a 440A4 is not connected on the
line, or the jumper is not set to ON in any of the other sets on the line.
Switch Administration
The 8503T voice terminal should be administered as an ISDN 7505 voice terminal.
Note: The three call appearance/feature buttons can be used for call appearances or
features, but, for most effective use of the voice terminal, it is strongly suggested
that all three buttons be administered for call appearances.
Power Failure Operation
The 8503T voice terminal cannot be used as an emergency station during power failure transfer
conditions.
FCC Registration
The 8503T voice terminal is FCC registered.
Hearing Aid Compatible
This voice terminal is compatible with the inductively coupled hearing aids prescribed by the FCC.
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