Agilent/Keysight U9391C

The Keysight U9391C is a comb generator for precision phase calibration of nonlinear measurements on the Keysight PNA-X nonlinear vector network analyzer. It calibrates PNA and PNA-X network analyzers for phase and delay measurements of frequency converters without requiring separate reference or calibration mixers. Built on InP MMIC technology, the U9391C delivers superior phase stability and excellent amplitude and phase flatness, qualifying it as a precision calibration phase reference standard.

Technical Specifications

Frequency Performance

• Output frequency: 10 MHz to 26.5 GHz


• Input frequency: 10 MHz to 6 GHz


• Minimum output power per picket: -80 dBm at 10 MHz input PRF


• Input power range: -15 dBm to +15 dBm Harmonic Generation

The device generates frequency harmonics at integer multiples from an RF input signal with 10 MHz minimum tone spacing. A customer-selectable, USB-controlled frequency divider provides divide ratios of 1, 2, 4, 8, or 16, enabling broad harmonic spacing flexibility. Drive frequency can be set at 1, 2, 4, 8, or 16 times the pulse repetition frequency. Power & Control

• DC power supply: 15 ± 10% Vdc at 300 mA nominal


• USB interface for primary control and calibration data retrieval


• Embedded calibration data accessible directly by PNA-X via USB


• Trigger output for synchronization with pulse repetition frequency Physical & Connectivity

Rugged 3.5-mm, 2.4-mm, and 1.85-mm bulkhead connectors provide high repeatability. Output connectors available in female or male configurations. A sine-to-square wave converter is included as standard.

Key Features

• Superior phase stability from InP MMIC technology


• Excellent amplitude and phase flatness across operating range


• Plug-and-play operation with PNA-X NVNA


• Simple USB-controlled frequency divider for flexible harmonic spacing


• Integrated trigger output for PRF synchronization

Typical Applications

• Nonlinear vector network analyzer phase calibration


• Frequency converter phase and delay measurements


• Precision calibration reference standard

Compatibility & Integration The U9391C integrates directly with Keysight PNA and PNA-X network analyzers via USB. Multiple units require separate power supplies for nonlinear measurements. Plug-and-play connectivity eliminates external calibration mixer requirements.