Agilent/Keysight 85531B

The Keysight 85531B is a temperature-characterized CalPod calibration module designed for PNA family network analyzers operating across wide temperature ranges. It enables rapid calibration refresh without removing the device under test or reconnecting calibration standards, while compensating for thermal effects on test cables and connectors. The CalPod integrates with Keysight's measurement ecosystem to simplify multi-port and multi-path characterization.

Technical Specifications

• Frequency Range: 100 MHz to 20 GHz


• Amplitude Re-correction: ±0.05 dB (typical)


• Phase Re-correction: ±1.5° (typical)


• Directivity Re-correction: -38 dB (typical)


• Temperature Compensation Range: -30 °C to +80 °C


• Insertion Loss: 3.5 dB maximum (100 MHz to 10 GHz); 4.0 dB maximum (10 GHz to 20 GHz)


• Return Loss at RF2 Output: 12.0 dB minimum (100 MHz to 5 GHz); 9.0 dB minimum (5 GHz to 20 GHz)


• Connectors: 2.92 mm male (RF1 input), 2.92 mm female (RF2 output)


• Dimensions: 70 mm × 29 mm × 14 mm (excluding connectors)


• Weight: Approximately 100 grams

Key Features

• Calibration refresh capability without DUT removal or standard reconnection


• Temperature characterization data delivered on included USB drive


• ECal module characterization support for simplified multi-port measurements


• Thermal chamber testing optimization

Typical Applications

• Temperature-dependent device characterization in thermal chambers


• Rapid calibration updates during extended measurement campaigns


• Multi-port and multi-path network analyzer measurements

Compatibility & Integration The 85531B operates with Keysight PNA-X N524xA, PNA N522xA, and PNA-L N5231/32/34/35/39A analyzers. It also supports M937xA series PXIe vector network analyzers. Operation requires an 85523B CalPod Controller and compatible drive cables (85552A 20 GHz or 85553A 40 GHz). When controlling more than four CalPods, the 85556A fan-out cable splitter is required. Modern PNA firmware no longer requires Options 302 and 304 for temperature-characterized CalPod compatibility.