Overview

The Yeastar O2 module is a compact interface card designed to connect traditional analog telephone lines to modern IP-based communication systems. Equipped with two FXO ports, it allows businesses to integrate PSTN connectivity into their existing PBX environment without complexity. This module is compatible with Yeastar S-Series and P-Series systems, making it a practical choice for organizations transitioning from legacy telephony to VoIP while maintaining access to analog lines.

Description

The Yeastar O2 FXO module (Part Number YST-O2 ) enables seamless integration between analog PSTN lines and IP PBX systems. With two RJ11 FXO ports, it supports reliable call routing, fallback options, and hybrid telephony deployments. Designed for compatibility with multiple Yeastar PBX models, it delivers stable performance with built-in echo cancellation and flexible signaling support, ensuring consistent call quality and efficient communication management.

Features

Connectivity and System Integration
This module is built to bridge the gap between analog infrastructure and IP telephony. By terminating up to two PSTN lines, it ensures businesses can maintain external line access while benefiting from VoIP functionality. It is particularly useful for backup routing, legacy device support, or environments where analog lines remain essential.

Supported systems include Yeastar S412, S20, S50, S100, S300, as well as P-Series models such as P550, P560, and P570 . For the P560 and P570, an EX-08 expansion board is required to enable compatibility.

Technical Details and Capabilities
Key technical elements are structured below for clarity:

• 2 RJ11 FXO ports for PSTN line termination
• Ring frequency detection range of 15 to 50 Hz
• Ring voltage detection above 30 VRMS depending on FXO mode
• Integrated echo cancellation for improved voice clarity
• Designed for two-way connection to PBX or key system trunks

The module also supports multiple signaling modes, allowing flexibility across different telephony environments:

• Foreign Exchange Office connectivity for standard trunk integration
• Foreign Exchange Station defined network access for carrier services
• Private Line Automatic Ringdown for direct point-to-point communication

Deployment Considerations
The Yeastar O2 module (YST-O2 ) is suited for businesses that require a hybrid telephony setup or need to preserve analog connectivity within a VoIP system. Its compact design allows easy installation into compatible PBX units, while its functionality ensures consistent performance across various use cases such as failover routing, branch office connectivity, or legacy system support.

Specifications

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Specifications
Product Code	YR-O2
Ports	2 RJ11 FXO Ports
Supported Model	S412, S20, S50, S100, S300, P550, P560, P570
Ring Frequency Detection	15~50 Hz
Ring Voltage Detection	30+ VRMS (depend on the FXO mode)
Termination	PSTN Lines
Echo Cancellation	Support
Signaling Modes	Foreign Exchange Office: 2 way connection to PRX or key system trunk.
	Foreign Exchange Station Defined Network: provides access to major carrier services.
	Private Line Automatic Ringdown (PLAR)-point-to-point unswitched connections.