Never Sacrifice Capability or Portability

Keysight's FieldFox portable analyzers are equipped to handle your toughest working environments during routine maintenance, in-depth troubleshooting, and anything in between. Choose the software-enabled FieldFox configuration that best meets your needs.

  • Base model includes a signal analyzer
  • Add software-defined measurement functions according to your needs.
  • Capture elusive signals with 120 MHz of gap-free, real-time bandwidth.
  • Characterize radar pulse profiles with a portable solution.
  • Make accurate spectrum analyzer measurements (± 0.2 dB) without warmup.
  • Perform over-the-air measurements for 5G NR and LTE.
  • Use GPS/GNSS for geolocation and timestamping.
  • Analyze I/Q data for RF signal monitoring and analysis.
  • Carry one lightweight unit at 3.4 kg (7.4 lb).

Key Specifications

Number of Built-In Ports
2 ports
Maximum Frequency
44 GHz
Number of Built-In Ports
Maximum Frequency
2 ports
44 GHz
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Additional SA Based Features:
Real-Time Spectrum Analysis
Noise Figure Measurements
Over-The-Air Measurements
Built-In Power Meter
Extended Range Transmission Analysis (ERTA)
AM/FM Tune and Listen
Cable and Antenna Analysis
Field Strength Measurement
SCPI Code Compatibility
Stimulus Response
89600 VSA Software
Over-The-Air LTE FDD and 5GTF
110 MHz
Bandwidth Options:
10 MHz
40 MHz
120 MHz
Cable and Antenna Analyzer:
DANL @1 GHz:
-163 dBm
Form Factor:
Frequency Range:
DC to 44 GHz
Instrument Type:
Signal Analyzer
Maximum Analysis Bandwidth:
120 MHz
Maximum Frequency:
44 GHz
Maximum Real-Time Bandwidth:
120 MHz
Number of Built-In Ports:
2 ports
Output Power:
Up to 6 dBm
Overall Amplitude Accuracy:
+/- 0.2 dB
Overall Amplitude Accuracy:
+/- 0.2 dB
Phase Noise @1 GHz (1 MHz offset):
-125 dBc/Hz
Phase Noise @1 GHz (10 kHz offset):
-114 dBc/Hz
Phase Noise @1 GHz (30 kHz offset):
-114 dBc/Hz
Phase Noise at 1 GHz, 1 MHz offset:
-125 dBc/Hz
Phase Noise at 1 GHz 10 kHz offset:
-114 dBc/Hz
Power Measurement Using USB Sensor:
CW or Swept-Frequency
RF Pulse Test with Peak Sensor
SA Start Frequency:
5 kHz
Spectrum Analyzer:
Yes - Standard
Spur Free Dynamic Range:
> 104 dB
Standard Attenuator Range:
40 dB
Standard Attenuator Step:
5 dB
Standard Attenuator Step:
5 dB
System Features:
GPS Receiver - Internal Only
Remote Control Capability
Built-In DC Source
TOI @1 GHz (3rd Order Intercept):
+ 5.1 dBm
Vector Network Analyzer:

N9961B FieldFox Handheld Software

Configure your FieldFox handheld analyzer to meet your specific measurement needs with powerful software options engineered to deliver precise measurements in the field.

  • Carry one portable instrument that supports over 20 different measurement functions.
  • Configure as a spectrum analyzer, built-in power meter, tracking generator, and more.
  • Order software pre-installed or upgrade an existing instrument.
PathWave Vector Signal Analysis Software

PathWave Vector Signal Analysis (89600 VSA) Software

  • Record signals in the field and evaluate them later using 89600 VSA.
  • Demodulate and perform comprehensive vector signal analysis to optimize your deployment.
  • Decode and verify MAC, RLC, and RRC-layer messages across multiple radio frames.
  • Analyze and troubleshoot signals in cellular, wireless-connectivity, aerospace, defense, and general-purpose applications.

Interested in the N9961B?

What's Included With Your Purchase

Rechargeable battery, carrying case, and charging ford for FieldFox
  • AC/DC adapter
  • Localized power cord
  • Quick Reference Guide
  • Rechargeable Li-ion battery
  • Soft carrying case with backpack and shoulder straps

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