Agilent/Keysight N9935C

The Keysight N9935C FieldFox C is a handheld microwave spectrum analyzer engineered for field testing and installation of microwave communication systems. This portable unit delivers advanced measurement capabilities in a rugged 3.4 kg package, supporting 5G NR, LTE, and broadband signal analysis across 3 kHz to 10 GHz.

Technical Specifications

• Frequency Range: 3 kHz to 10 GHz


• Amplitude Accuracy: ±0.15 dB (without warmup); ±0.3 dB


• System Dynamic Range: >104 dBc


• DANL @ 1 GHz: -164 dBm


• Third Order Intercept (TOI) @ 1 GHz: +10 dBm


• Phase Noise @ 1 GHz: -124 dBc/Hz (1 MHz offset), -112 dBc/Hz (10 kHz offset), -113 dBc/Hz (30 kHz offset)


• Analysis Bandwidth: 120 MHz maximum


• Real-Time Bandwidth: 120 MHz maximum


• IQ Streaming Bandwidth: 1 MHz maximum


• IF Bandwidth Options: 3 Hz through 100 kHz (10 discrete steps)


• Attenuator: 0 to 40 dB in 5 dB steps


• Ports: 2 built-in


• Internal Sources: 1


• System Impedance: 50 Ω nominal; 75 Ω with adapter and calibration kit


• Display: 6.5" LCD-LED


• Weight: 3.4 kg (7.4 lb)

Key Features

• Real-time spectrum analysis with 120 MHz gap-free capture


• Accurate measurements without warmup period


• Native 5G NR and LTE over-the-air measurement support


• Software-defined architecture enabling field configuration and future enhancements


• GPS/GNSS integration for geolocation and timestamping


• Multiple measurement modes: spectrum analysis, signal analysis, and interference detection

Measurement Functions & Options Base unit includes spectrum analyzer and real-time analysis. Optional modules support power metering (Option 310), reflection measurements including RL and VSWR (Option 320), time gating (Option 238), extended range transmission analysis (Option 209), LTE FDD/TDD over-the-air testing (Options 370/371), 5G NR OTA measurements (Option 378), and directional finding via TDOA and angle-of-arrival (Options 390/391).

Package Contents Standard kit includes spectrum analyzer, AC/DC adapter, localized power cord, rechargeable Li-ion battery, soft carrying case with backpack and shoulder straps, and quick reference guide.