Keysight's FieldFox is a family of handheld RF, microwave, and millimeter-wave analyzers built to bring benchtop-class measurement precision into the field. The series spans frequency coverage from 4 GHz up to 50 GHz and is offered in three configurations: RF and microwave combination analyzers, microwave vector network analyzers, and microwave spectrum analyzers. A combination analyzer integrates a cable and antenna tester, a vector network analyzer, and a spectrum analyzer in a single sealed instrument weighing as little as 6.6 lb (3.0 kg).

FieldFox is designed for installation and maintenance work across demanding field environments. Listed applications include installing and maintaining cellular systems with the cable and antenna (CAT) tester, radar installation and maintenance through the Ka and Q bands, and accelerating work at satellite ground stations where uplink and downlink signals, cables, waveguides, and antennas must be validated. It also serves as a companion tool on the R&D bench and brings as many as 20 instrument capabilities into engineering classes and labs, freeing high-performance benchtop instruments for other work.

ValueTronics stocks and holds its own inventory in a 20,000-square-foot secure warehouse at 1675 Cambridge Drive in Elgin, Illinois, so the instruments we list are equipment we keep on hand.

Brand Heritage

The FieldFox line carries the measurement heritage of a company that has changed names over the decades. Hewlett-Packard's test and measurement business was spun off as Agilent Technologies in 1999, and that business became Keysight Technologies in 2014. Instruments and documentation from all three eras belong to the same engineering lineage.

Compare Other Models in This Series

The FieldFox family is organized into three configurations that share a common rugged platform: RF and microwave combination analyzers, microwave vector network analyzers, and microwave spectrum analyzers. A combination analyzer bundles a cable and antenna tester, a vector network analyzer, and a spectrum analyzer together, while the dedicated VNA and spectrum analyzer models focus on a single measurement discipline.

Across the series, frequency coverage scales from 4 GHz to 50 GHz, and every model is built on the same sealed, MIL-spec chassis with field-upgradeable software license keys. The configuration you choose determines which base measurements are standard and which capabilities are added as options.

Each new model linked below is its own dedicated product page with condition-matched pricing. Select the specific FieldFox model and frequency coverage that fits your application to see its availability and price.

The clearest difference between models is frequency coverage and configuration. Combination analyzers (N9913A through N9918A and N9950A/N9951A/N9952A) cover CAT and VNA frequencies and add spectrum analysis up to 50 GHz; dedicated vector network analyzers (N9925A through N9928A) cover up to 26.5 GHz; and dedicated spectrum analyzers (N9935A through N9938A and N9960A/N9961A/N9962A) cover up to 50 GHz. Test port connectors change with frequency, from Type-N (f) on lower-frequency models to 3.5 mm and NMD 2.4 mm on the higher-frequency units.

Capabilities also differ by configuration and processor: QuickCal is not available on the N995xA models, and advanced modes such as real-time spectrum analysis, I/Q analysis, noise figure, and Over-the-Air measurements require the CPU2 fast processor. The comparison table below details which functions are standard, optional, or unavailable for each model.

Additional differences in specifications beyond the few shown above are not listed here — see each model's full specifications below.

Product Core & Specifications

Important: QuickCal is not available on N995xA analyzers.

Important: FieldFox capabilities are field-upgradeable and are added via software license keys; select the capabilities you need today and add more later. Many measurement modes are options that are not included in the base instrument.

Important: The Real-Time Spectrum Analyzer (RTSA), I/Q Analyzer (IQA), Noise Figure (NF), Analog Demodulation, Over-the-Air (OTA) LTE FDD/5GTF, and 89600 VSA software connection require the CPU2 fast processor. All N995xA and N996xA analyzers include CPU2; on other FieldFox models the serial number prefix (MY5607/SG5607/US5607) or an N9910HU-100/200/300/400 upgrade is required for CPU2.

Important: The built-in variable-voltage DC bias source can power amplifiers under test and bias tower-mounted amplifiers (TMA); bias tees are available separately.

Important: Power measurements using a USB power sensor, and pulse measurements using a USB peak power sensor, require a Keysight USB power sensor / USB peak power sensor (connected externally; not part of the base instrument).

Important: For the N9938A, order Option 100 for 3.5 mm (m) test port connectors instead of the standard Type-N (f); Option 100 is a prerequisite for Option 320 on the N9938A.

Important: I/Q Analyzer and 89600 VSA software connection require a spectrum analysis option on FieldFox and are not supported on model N9912A.

Recommended pairing: for portable noise figure work, FieldFox supports Keysight 346A/B/C/K01/K40 noise sources and U7227A/C/F or U7228A/C/F USB preamplifiers.

About this New unit

This is a brand-new, factory-sealed unit, supplied exactly as it arrives from the manufacturer and backed by the full manufacturer warranty. For the exact configuration, available options, included accessories, or current lead time for your application, our Test Architects can confirm the details before you order.

ValueTronics supplies both new and used test and measurement equipment. New units ship factory-sealed, exactly as received from the manufacturer; every used unit is inspected and functionally verified in-house at our 20,000 sq ft secure facility in Elgin, Illinois before it ships. Our Test Architects can help you select the condition, calibration, and configuration that fit your application.

Please review the Manufacturer's Data Sheet to verify published specifications. Feedback on this webpage is always welcome — please reach out to your Test Architect at any time for questions or concerns. Thank you, we truly appreciate you being our customer.