SO Module FXO & FXS

Key Features

• 1 × FXO Port (RJ11): Connects one analog PSTN (POTS) telephone line.
• 1 × FXS Port (RJ11): Connects one analog telephone or fax device.
• PSTN Fallback/Failover: Ensures analog phones can make/receive calls directly over the PSTN line if the PBX system powers down or fails.
• Echo Cancellation: Built-in support to improve voice quality.
• Termination Types: Supports standard PSTN lines and analog telephone/fax termination.

Technical Specifications (Typical)

• FXO Ring Frequency Detection: ~15 – 50 Hz
• FXS Ring Frequency: ~25 Hz
• Ring Voltage: ~85 V
• Terminating Impedance Option: ~600 Ω
• Port Types: 1 × FXO RJ11, 1 × FXS RJ11

Compatibility

Compatible with modular Yeastar S-Series and P-Series IP PBX models (such as S20, S50, S100, S300, P550, P560, P570) and older MyPBX platforms that support telephony modules.

Use Cases

• Add one analog PSTN trunk and one analog extension to an IP PBX.
• PSTN failover fallback to maintain basic voice service if the VoIP PBX is offline.
• Support for analog telephones and fax machines alongside VoIP infrastructure.