The Keysight N9925A FieldFox is a handheld microwave vector network analyzer delivering lab-grade measurements in a field-portable format. Operating from 30 kHz to 9 GHz with 50 Ω system impedance, this 6.6 lb (3.0 kg) instrument provides S-parameter analysis, time-domain reflectometry, cable and antenna characterization, and vector voltmeter functionality across demanding environments from -10 to 55 °C.
Technical Specifications
Frequency & Dynamic Range
• Frequency Range: 30 kHz to 9 GHz
• Dynamic Range: Up to 95 dB; 100 dB achievable in S21 VNA mode with 100 Hz IFBW
• Trace Noise (300 Hz IFBW, Port 1 or 2): ±0.004 dB rms magnitude, ±0.07 deg rms phase (≥300 kHz)
Source Output
• Maximum Leveled Output Power: 5 dBm
• Power Setting: 1 dB steps across range
• Low Power Mode: -45 dBm (nominal)
• Default VNA Power: -15 dBm (manual, flattened)
Input & Receiver
• Maximum Input Level: +27 dBm CW (0.5 watts) or ±50 VDC
• Receiver Compression (500 MHz to 1 GHz): +10 dBm, 0.15 dB compression
• Receiver Compression (1 GHz to 26.5 GHz): +10 dBm, 0.10 dB compression
System Configuration
• Ports: 2 built-in
• Impedance: 50 Ω nominal; 75 Ω with adapter and calibration kit
• Power Source: Battery-operated
• Operating Temperature: -10 to 55 °C
• Weight: 6.6 lb (3.0 kg)
– Key Features
• Transmission/reflection measurements (S11, S21) with magnitude and phase
• Optional full 2-port S-parameters (S11, S21, S12, S22)
• Time-domain reflectometry and mixed-mode S-parameters with option
• Vector voltmeter and power measurement modes
• Multiple calibration methods: CalReady, OSL, response, enhanced response; optional TRL and Unknown Thru
• Calibration engine matched to benchtop ENA and PNA analyzers
– Typical Applications
• Cable and antenna field verification
• Component S-parameter characterization
• Transmission line and return loss analysis
• In-situ system integration testing
– Compatibility & Integration
The N9925A accepts both 50 Ω and 75 Ω system impedances with appropriate calibration kits. Its measurement engine aligns with Keysight benchtop network analyzer platforms, ensuring data consistency across lab and field workflows.
