B‑Series handheld microwave analyzer (to ). Keysight N9951B FieldFox Handheld Microwave Analyzer is designed for professional EMC testing workflows, delivering reliable performance for emissions and immunity evaluations. Typical applications include pre-compliance, debug, and certification support across automotive, aerospace, medical, and industrial sectors. Engineered for accuracy and repeatability, it integrates smoothly with lab automation and common EMC standards. Keywords: EMC testing, EMI/EMS compliance, RF immunity, radiated & conducted emissions, IEC/EN 61000, CISPR, EMI receiver, spectrum analysis.