The Keysight 81989A is a compact tunable laser source for optical device characterization across the S+C transmission band. This plug-in module delivers continuous mode-hop free tuning from 1465 nm to 1575 nm with output power ranging from +10 dBm to +14.5 dBm peak, making it ideal for testing optical amplifiers and passive components in single-channel and DWDM applications. Built-in wavemeter and coherence control provide wavelength accuracy to ±20 pm and suppress stimulated Brillouin scattering without external monitoring equipment. The 81989A integrates into Keysight 8163A/B, 8164A/B, and 8166A/B mainframes as a single-slot module, offering a cost-effective platform for nonlinear effect testing and transient characterization of erbium-based amplifiers.
Technical Specifications
• Wavelength Range: 1465 nm to 1575 nm (110 nm tuning span)
• Output Power: +14.5 dBm peak typical; +13 dBm from 1525–1575 nm; +10 dBm across full range
• Wavelength Resolution: 5 pm (625 MHz at 1550 nm)
• Absolute Wavelength Accuracy: ±20 pm with built-in wavemeter; ±100 pm without
• Tuning Time: Typically 3 seconds for 100 nm sweep
• Spectral Width: 100 kHz
• Polarization Extinction Ratio: 16 dB typical
• Power Stability: 0.01 dB
• Mode-hop Free Tuning: Continuous across full wavelength range
• Warm-up Time: 1 hour
• Laser Classification: Class 1M
• Operating Temperature: 10 to 35 °C
• Dimensions: 75 × 32 × 335 mm; 0.95 kg
– Key Features
• Built-in wavemeter eliminates need for external wavelength monitoring
• Integrated coherence control suppresses SBS and interference artifacts
• Panda fiber output with TE mode orientation (slow axis aligned to connector key)
• Full mode-hop free tunability enables stable multi-wavelength testing
• Time-domain extinction (TDE) method support for transient amplifier testing
– Typical Applications
• Optical amplifier characterization and gain/noise figure measurement
• Nonlinear effect testing in optical components and systems
• DWDM device validation and single-channel component assessment
• Erbium-doped fiber amplifier (EDFA) transient response analysis
– Compatibility & Integration
• Mainframe compatibility: Keysight 8163A/B, 8164A/B, 8166A/B series
• Requires Agilent 81000xI-Series connector interface (sold separately)
• Options: 071 (PMF straight contact), 072 (PMF angled contact)
• Calibration interval: 2 years
