10Gtek 1.25G SFP Bidi Transceiver Singlemode LC - Reliable 2km Link

In this review the 10Gtek 1.25G SFP Bidi Transceiver is evaluated for small networks and edge deployments where a single-fiber, bidirectional link matters. The bottom line: it is a practical, plug-and-play SFP module for technicians who need a simple way to extend Gigabit connectivity over singlemode fiber up to about 2 to 3km. The reviewer found it especially useful for replacing vendor optics or linking Ubiquiti and open-switch equipment without reconfiguring ports.

Key Features

• Bidirectional Single LC: Uses a 1000BASE-BIDI design to carry transmit and receive on a single LC connector, which simplifies cabling in constrained pathways.
• Dual Wavelength Options: The pair includes modules with Tx1310nm/Rx1550nm and Tx1550nm/Rx1310nm so each end of the link pairs correctly for singlemode operation.
• DDM Diagnostics: Digital Diagnostic Monitoring lets administrators check transmit and receive status in real time to spot signal issues quickly.
• Wide Compatibility: Works with Cisco 1000BASE-BX3, Ubiquiti UniFi UF-SM-1G-S and many open switches for straightforward interoperability.
• Tested Reliability: Each transceiver is individually tested in the manufacturer lab and shipped after verification, reducing the chance of DOA units.

Who It's For

This transceiver pair is aimed at network engineers, integrators, and IT teams who need to convert existing singlemode fiber runs into a Gigabit link without changing fiber plant or adding a second fiber. It is also a good choice for sites using Ubiquiti UniFi or other open-switch hardware where vendor optics are not required.

Those who should look elsewhere include users who require multimode fiber support, links longer than 3km, or higher than 1.25Gbps speeds; for those needs consider modules rated for longer reach or higher data rates.

Pros & Cons

Pros

• Plug-and-play compatibility with common switches makes deployment fast and predictable.
• DDM provides valuable real-time monitoring to troubleshoot link quality.
• Individually tested units reduce the risk of discovering faulty optics after installation.

Cons

• Reach is limited to about 2 to 3km, so it is not suitable for longer backbone links.

Specifications

Form Factor	SFP
Data Rate	1.25Gbps
Fiber Type	Single Mode Fiber (SMF)
Wavelength	Tx 1310nm / Rx 1550nm and Tx 1550nm / Rx 1310nm
Reach	Approximately 2 to 3km
DDM	Supported

Our Verdict

The 10Gtek 1.25G SFP Bidi Transceiver pair is a practical, cost-effective option for anyone needing a quick, reliable Gigabit link over existing singlemode fiber up to roughly 2 to 3km. With DDM, wide compatibility, and per-unit testing, it represents good value for network teams replacing optics or linking mixed-vendor hardware, provided the required reach and speed match the module's capabilities.

Frequently Asked Questions

Will this work with Ubiquiti UniFi switches?
Yes, customers report it works flawlessly with Ubiquiti UniFi switches and it is listed as compatible with UF-SM-1G-S style ports.

How far can the link run?
The modules are specified for about 2 to 3km over singlemode fiber, so plan links within that range for reliable operation.

Can I monitor the transceiver health?
Yes, the transceivers support Digital Diagnostic Monitoring (DDM) so transmit and receive parameters can be checked in real time.