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PABX (Private Automatic Branch Exchange)
A PABX is a telephone exchange in one business or building (where a dial 9 is
needed for an outside line). It connects to one or more outside telephone lines
and has two or more extentions within the business or building. See Fig 11.
DualCom may be connected to one of the outside telephone lines where they
are the analogue PSTN type.
The extentions within the building may be analogue or digital. Where an extention
is
analogue
, a normal phone or fax machine may be connected. DualCom
may be connected here. See Fig 12.
Where the PABX is mains powered and it is not battery backed-up then the line
to the DualCom may fail in the event of a mains failure. This may make
this
type of telephone connection unsuitable for DualCom
.
Where the extention is a digital line then a special ‘feature phone’ is usually
required, provided by the manufacturer of the PABX equipment. DualCom can
not
be
directly
connected to any type of digital telephone line.
PABX with connection to Analogue PSTN Line
Fig 11