The Keysight N9961A FieldFox is a handheld microwave spectrum analyzer delivering lab-grade measurement performance in field-deployable form. Operating from 9 kHz to 44 GHz, this portable instrument provides rapid amplitude accuracy of ±0.5 dB at power-up with zero warm-up time, enabling immediate deployment for microwave system troubleshooting and maintenance. The N9961A combines spur-free dynamic range exceeding 104 dB, 10 MHz real-time bandwidth for capturing intermittent signals, and phase noise of −111 dBc/Hz at 10 kHz offset into a rugged 3.2 kg package meeting MIL-PRF-28800F Class 2 environmental standards.
Technical Specifications
• Frequency Range: 9 kHz to 44 GHz (usable down to 5 kHz)
• Amplitude Accuracy: ±0.5 dB at power-up, no warm-up required
• Spur-Free Dynamic Range: >104 dB or >105 dB (bandwidth-dependent)
• Phase Noise: −111 dBc/Hz at 10 kHz offset
• Real-Time Bandwidth: 10 MHz gap-free
• Maximum IQ Streaming Bandwidth: 1 MHz
• Test Ports: 2× NMD 2.4 mm (m); mechanically compatible with 1.85 mm connectors; precision adapters required for SMA, 3.5-mm, and 2.92-mm mating
• Battery Life: 3.5 to 4 hours
• Display: 6.5″ or 5.7″ color LCD with touch screen
• Dimensions: 292 mm H × 188 mm W × 72 mm D
• Weight: 3.2 kg (7.1 lb)
• Operating Temperature: −10°C to +55°C
• Environmental Rating: MIL-PRF-28800F Class 2; dust-free design, no fans or vents
– Key Features
• Spectrum analysis with channel power, adjacent channel power, and occupied bandwidth measurements
• Optional tracking generator covering full frequency band
• Optional interference analyzer with spectrogram display and recording
• Optional built-in power meter
• Optional pulse measurement capability for radar and electronic warfare characterization
• VSWR and reflection measurement capabilities
• Optional pre-amplifier
– Typical Applications
Field troubleshooting of microwave systems, spectrum monitoring, interference identification, RF pulse characterization, and transmission line assessment.
– Compatibility & Integration
Supplied with AC/DC adapter, rechargeable battery, soft carrying case, LAN cable, and documentation. Test port adapters enable connection to standard RF connectors.
