If the paging amplifier is the type that provides a microphone input a 1:1 Audio Isolation transformer with a 600
to 900 ohm impedance must be connected between the extension port and the microphone input. A Radio Shack
1:1 Audio Isolation Transformer (p/n 273-1374) was used by Inter-Tel to verify this operation, but any
transformer with a similar specification will work. In addition, commercial 1:1 (600 - 600 ohm) transformers are
available from most sound system suppliers.
Connecting a PC or Printer to the Serial Port
A six-foot cord with a four-way RJ11 plug on one end and a six-way RJ plug on the other is provided. An RJ-to-
DB9 adapter is also provided.
Connect the cord to the four-way RJ11 connector on the CCU.
Connect to the PC using either the six-way RJ plug or the cord and DB9 converter as required.
The pinouts from the RS 232 interface of the DB9 to the RJ11 are:
Central Bell
If a central bell is required, connect it to a spare extension position and include the extension in the Ringing
Groups that require the bell.
Extension Module MDF Connections
The connections on the Extension module are shown below.
•
Eight RJ11 connectors for the extensions.
•
Four RJ11 connectors for the CO lines.
•
Two RJ11 power failure connectors.
DB9 connector
RJ11 plug
2
4
3
3
5
1
Installation and Maintenance Manual
EncoreCX
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