Installation guide

AP-IP300 IP Phone Installation Guide Version 1.0
AddPac Technology Proprietary & Documentation
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Connecting PSTN (FXO) interface
The FXO PSTN interface port is available when PSTN access-line is used or impossible to
make a VoIP call due to network problem. PSTN backup is implemented by connecting PSTN
access-line to PSTN port, illustrated as following figure.
(Figure 3-3) AP-IP300 IP Phone PSTN Interface Connection