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Variable Attenuator — FTBx-3500


Ideal for transceiver testing and system verification in demanding 24/7 production environments.

Technical information

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Key features

  • Outstanding spectral uniformity
  • Ideal for BER testing and system verification
  • Integrated power monitoring options (on both singlemode and multimode models), for easy power setting and improved stability
  • Designed for 24/7 production, with minimal maintenance
  • Fast settling time for optimized efficiency


A Fully Programmable Solution with Remote Capabilities

Network equipment manufacturers and transceiver manufacturers know that variable attenuators are essential components of their test systems. They look for performance, user-friendliness, complete control of test parameters and advanced programming capability. EXFO’s FTBx-3500 Variable Attenuator combines innovative design techniques, high-quality components and meticulous calibration procedure.

The Only VOA with Full Remote UI Compatability

Ideal for bit error rate testing and system verification, the FTBx-3500 is the only variable optical attenuator (VOA) that offers a fully remote user interface (UI) and EXFO Multilink compatibility. It is also the only VOA on the market to offer a benchtop unit, which can be controlled remotely or using a touchscreen.

Option: Automatic Power Monitoring

The power monitoring option allows the attenuator output power level to be set directly. When enabled, this function ensures power stability, even if the source power fluctuates. This option also simplifies test setups, eliminating the need for an external power meter.

Rugged and Reliable

Flexible, fully programmable and built for both singlemode and multimode applications, the FTBx-3500 features an extremely rugged design allowing 24/7 operation for years without maintenance.

Related Resources

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EXFO Multilink

Specification sheets

EXFO Multilink connects multiple users to EXFO modules and LTB-8 platforms remotely, through any web browser.

Last updated: 2017-07-21


Specification sheets
Last updated: 2017-06-13

Last updated: 2017-03-06

Network Equipment Manufacturers

Brochures and Catalogs

Discover EXFO’s innovative and multiservice converged networks testing solutions for 100G, 200G, 400G and beyond, addressing the needs of NEMs around the globe with regard to design, verification and manufacturing.

Last updated: 2016-09-19


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