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81613A Return Loss Module with integrated Laser Source

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Starting From US$ 14,539

Typical Configuration  

Typical Configuration

81613A Return Loss Module 1310/1550nm

  • R-51B-001-Z Return to Keysight Warranty - 3 years


Prices for: United States

* Prices are subject to change without notice. Prices shown are Manufacturer's Suggested Retail Prices (MSRP). Prices shown are exclusive of taxes.

Key Features & Specifications

  • Return loss dynamic range > 75 dB
  • Return loss uncertainty down to ±0.25 dB with external broadband source
  • Wide operating wavelength range: 1250 nm to 1640 nm
  • Built-in Power Monitor and Laser Source: 1310/ 1550 nm
  • Built-in step-by step guided wizard with 8163B mainframe


Keysight's 81613A Return Loss module is the tool of choice for measuring return loss (RL) and reflection of single-mode fiberoptic components. The module measures the optical power into and reflected back from the device under test and calculates and displays the return loss. Thorough built-in functionality provides the correct coupling and detection ratios and eliminates the effects of dark current and residual backscatter in the instrument setup to provide accurate measurements over a wide dynamic range.

The Return Loss modules can be used in any 816x Lightwave mainframe and with the internal Fabry-Perot light source or an external fixed-wavelength or tunable laser source. The performance and usability is enhanced by combination with a Keysight power sensor in the 8163B mainframe for simultaneous RL and insertion loss measurements, especially in combination with the 81610CC calibrated reference cable. Automated use is supported by the 816x Plug&Play Driver, which also supports use of the module for advanced swept-wavelength RL measurements.


  • The high RL dynamic range provides most accurate measurement of RL and IL up to 75 dB using the built-in sources and enables better product specifications.
  • One test setup can be used for DUTs in all transmission bands.
  • The built-in power monitor and built-in source provides RL measurements with highest stability and accuracy.
  • The built-in power monitor compensates power variations of the external light source, requiring referencing less often.
  • The built-in RTL-wizard simplifies accurate calibration and measurement.
  • Factory calibrated parameters let you instantly start with the return loss measurement.