Ubiquiti UF-SM-1G-S 1.25G SFP BIDI Transceiver - 10-20km Simplex LC

In this review the author examines the Ubiquiti UF-SM-1G-S compatible SFP BIDI transceiver from Jeirdus and concludes it is a practical replacement for network engineers who need a reliable bidirectional single-fiber link. The bottom line: this module delivers carrier-class 1.25 Gb/s performance over single LC simplex fiber for up to 20 km, making it a solid choice when conserving fiber or replacing failed SFPs is the priority. The review focuses on compatibility, real-world use, testing, and value for IT teams and integrators.

Key Features

• Bidirectional WDM: Uses TX1310nm/RX1550nm or TX1550nm/RX1310nm to send and receive on a single LC fiber, saving fiber cabling and simplifying link design.
• 1.25 Gb/s Data Rate: Supports 1000BASE-BX-U and 1000BASE-BX-D standards for gigabit Ethernet links over long distances up to 20 km.
• Wide Compatibility: Engineered to work with Ubiquiti and compatible with Cisco-class equipment thanks to Jeirdus compatibility lab testing and coding adjustments.
• Quality Assurance: Each transceiver is individually tested prior to delivery to ensure link reliability and reduce deployment issues.
• Regulatory and Warranty Coverage: Built from 100% new materials with CE and FCC markings and backed by a 3 year replacement plus lifetime warranty for long-term peace of mind.

Who It's For

The transceiver is aimed at network administrators, installers, and small to medium enterprise IT teams that need a cost-effective replacement for broken SFPs or who want to extend gigabit links over a single strand of fiber. It is particularly useful where fiber runs are limited and bidirectional WDM is the simplest solution to conserve cabling.

It is less appropriate for those who require multi-rate SFPs, specialty multimode links, or proprietary modules that depend on vendor-locked authentication beyond standard coding. Buyers who need multi-gig speeds above 1.25 Gb/s should look for other transceiver classes.

Pros & Cons

Pros

• Compatible with Ubiquiti WDM and many Cisco devices due to Jeirdus compatibility lab coding.
• Supports up to 20 km over single LC fiber, making it suitable for campus and metro links.
• Individually tested units and regulatory compliance reduce deployment headaches.

Cons

• Limited to 1.25 Gb/s so it does not cover newer multi-gig or 10 GbE requirements.

Specifications

Form Factor	SFP (1.25 Gb/s)
Fiber Type	Single-mode simplex LC
Wavelength	TX1310nm/RX1550nm or TX1550nm/RX1310nm
Standards	1000BASE-BX-U and 1000BASE-BX-D
Maximum Distance	Up to 20 km
Compliance	CE, FCC
Warranty	3 year replacement and lifetime warranty

Our Verdict

For technicians who need a dependable, cost-conscious replacement for failed or missing SFPs, the Jeirdus compatible Ubiquiti UF-SM-1G-S style BIDI transceiver offers clear value: tested compatibility, single-fiber WDM operation to 20 km, and regulatory coverage with warranty support. It is a practical pick for gigabit single-mode links but not for those who require multi-gig bandwidth.

Frequently Asked Questions

Is this module compatible with Ubiquiti devices?
Yes. It is designed to be compatible with Ubiquiti WDM SFP modules and has been coded and tested for broad interoperability.

What distance can this transceiver support?
It supports links up to 20 km over single-mode fiber using a simplex LC connector.

Does the module carry warranty and certifications?
Yes. It is made from new materials, carries CE and FCC markings, and includes a 3 year replacement plus lifetime warranty.