NEC Xen Master System Hardware Manual page 61

May 2001
7.2.3 PBR Requirements
The Xen Master and Xen Axis systems have four built-in
Push Button Receiver (PBR) circuits on the CPUB ( )-U13
ETUs and B48( )-U13 KSU mainboard respectively. The
PBR circuit detects and translates DTMF tones generated
by Single Line Telephones, facsimile machines, modems,
and analogue voice mail ports. Incoming DTMF signals
can also be detected from a CO trunk using the DISA
features. The system Auto Attendant feature and DISA
feature must use the PBR circuits built in to the CPU card/
mainboard.
An optional PBR( )-U13 ETU can be installed providing an
additional four circuits. The number of PBR circuits
needed depends on the number of Single Line
Telephones, facsimile machines, modems, and analogue
voice mail ports needed. If Automated Attendant and DISA
trunks are connected to the system, these must also be
taken into consideration.
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