Attenuator BlueOptics SFA21XK4 LC 4dB Silver

The BlueOptics SFA21XK4 LC 4dB Silver attenuator provides a precise 4 dB reduction of optical signal power for multimode fiber links (50/125 µm) at 850 nm. Equipped with an LC/UPC simplex connector and a zirconia ceramic ferrule, this inline passive attenuator is designed to manage excessive transmitter power on short runs or within systems where receiver sensitivity must be protected. The silver housing and LSZH jacket meet industry requirements for installations that demand low smoke and halogen-free materials.

Advantages

The attenuator delivers stable and repeatable 4 dB attenuation with low insertion loss and high return loss thanks to quality polishing and ceramic ferrules. It is manufactured using branded fiber and precision connectors to ensure long life and up to 1500 mating cycles. Each unit is tested with interferometer and OTDR equipment and supplied with measured input loss and return loss values to ensure predictable performance in installed networks.

Suitable for

• Reducing transmitter signal power on short multimode fiber links (50/125 µm) at 850 nm
• Protecting receivers from oversaturation in data centers and telecom racks
• Field installations and patch panels using LC/UPC simplex connectors
• Environments requiring low-smoke, zero-halogen cabling materials

Key specifications

• Attenuation level: 4 dB (fixed)
• Fiber type: Multimode 50/125 µm
• Operating wavelength: 850 nm
• Connector type: LC/UPC simplex
• Ferrule material: Zirconia ceramic
• Insertion loss: low (factory measured per unit)
• Return loss: high (factory measured; optimized polishing)
• Temperature range: -40 °C to +75 °C
• Jacket material: LSZH (low smoke, zero halogen)
• Durability: up to 1500 mating cycles

How to use

Insert the LC/UPC simplex connector of the attenuator between the transmitter and the receiver or into the patch panel port where signal reduction is required. Ensure connectors and adapters are clean before mating to avoid contamination and increased loss. The device is passive and requires no power or configuration; once installed it provides the rated 4 dB attenuation. If multiple attenuators are used in series, add attenuation values to calculate total loss and verify that the resulting signal level remains within receiver sensitivity specifications.

Usage recommendations

Store and handle the attenuator in a clean environment and use dust caps when not connected. Verify measured loss and return loss values provided with the product against system requirements during installation. Avoid bending the fiber beyond recommended radii and do not expose the attenuator to temperatures outside the specified operating range to maintain performance and longevity.