Pub. 42004-442D
Models 10959-903 and 10959-904 Wall-Mount Audio Messenger Interface
Page 9 of 17
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Configuration
Opening the Unit
1.
Loosen the four screws on the front cover.
2.
Open the hinged front cover of the enclosure and turn it to the left.
Figure 4. AMI (open with connections, adjustments, and PCBAs labeled)
600-Ohm Line Termination Jumper Setting
Terminate the 600-ohm audio lines with 600 ohms for impedance matching. Use jumper
P5
, located on
the termination board to enable/disable impedance matching on the 600-ohm audio line connections (see
Figure 4 and Table 5).
Table 5. Termination PCBA—P5 Jumper Function
Jumper Output Position Function
P5
TB3-1, 2
600 ohms
1-2
600-ohm resistor connected (ADVANCE position)
2-3
default: unterminated
