SO Module

Manufacturer reference

Manufacturer details describe the cited version. Confirm the exact unit and intended system.

Function and configuration

Device class

FXS / FXO PBX module

Port functions

1 FXS port and 1 FXO port; not an S2 two-FXS or O2 two-FXO module.

Termination reference

PSTN line and analog telephone / fax machine reference; check exact line and endpoint electrical requirements.

FXO ring detection

15–50 Hz detection reference; separate from FXS ringing output.

FXS ring frequency

25 Hz ringing-frequency reference; not the FXO detection range.

Fallback reference

The manufacturer lists PSTN failover when system power is down; confirm the required line, endpoint and hardware arrangement.

Echo cancellation reference

Echo cancellation is listed; no numerical performance guarantee is established.

Terminating impedance option

600 Ω option in this document; verify actual line matching.

Legacy expansion-board reference

The S-Series guide lists SO Module among optional EX08 modules for S100/S300; actual hardware and firmware require confirmation.

Selection notes

• Confirm the complete supplied model, hardware version and firmware; optional boards, modules, licences, carrier service and local stock are not included or confirmed.
• Manufacturer references do not confirm ISD stock, price, delivery, package contents, local warranty or publication approval.
• PSTN fallback depends on a live analog PSTN line, an appropriate analog endpoint, the actual compatible PBX/module and power conditions; it is not VoIP, cellular or emergency-call continuity.
• This is a legacy S100/S300 EX08 installation reference, not an all-PBX or S412 compatibility approval.

Official documents

• Yeastar SO Module manufacturer datasheet inside official module ZIP
• Yeastar manufacturer original Y06
• Yeastar S-Series installation guide / exact S100,S300,S412,D30 sections

Manufacturer source checked 2026-10-20. The supplied unit and local terms require confirmation.