HP / Agilent 81561A Variable Optical Attenuator

The HP/Agilent 81561A is a variable optical attenuator plug-in module for the Lightwave Multichannel Platform series. It delivers precise attenuation control from 0 to 60 dB with 0.001 dB resolution across the 1200 nm to 1700 nm wavelength range, supporting single-mode fiber testing and optical power management in telecommunications applications.

## Technical Specifications

• **Attenuation Range:** 0 to 60 dB
• **Resolution:** 0.001 dB
• **Accuracy:** ±0.1 dB
• **Repeatability:** ±0.01 dB
• **Wavelength Range:** 1200 nm to 1700 nm
• **Fiber Type:** 9/125 µm single-mode (SMF28)
• **Insertion Loss:** Typically 1.7 dB
• **Return Loss:** Typically 60 dB
• **Maximum Input Power:** +22 dBm
• **Polarization Dependent Loss:** <0.05 dBpp
• **Settling Time:** Typically 100 ms
• **Shutter Isolation:** Typically 100 dB
• **Dimensions:** 75 mm × 32 mm × 335 mm
• **Weight:** 0.9 kg

## Key Features

• Integrated shutter for channel drop simulation and optical protection
• Automatic wavelength correction applied upon wavelength entry
• User calibration capability with relative attenuation display against reference power
• Angled fiber connector interfaces (connectors sold separately)

## Typical Applications

• Telecommunications system testing and validation
• Optical power level control and measurement
• Single-mode fiber characterization
• Channel attenuation simulation in multichannel optical systems

## Compatibility & Integration

The 81561A occupies a single slot in Agilent's Lightwave Multichannel Platform 8163A/B, 8164A/B, and 8166A/B series. Two angled fiber connector interfaces are required; each connector must be purchased separately.