Keysight (Agilent) N4000A SNS Series Noise Source 10 MHz to 18 GHz

The Keysight N4000A SNS Series Noise Source generates stable, repeatable noise signals across 10 MHz to 18 GHz for precision noise figure measurements. Engineered to maintain consistent impedance whether powered on or off, it eliminates gain fluctuations in the device under test that could be misattributed to noise - critical for characterizing low-noise devices and gain-sensitive components like GaAs FETs. The instrument delivers a nominal excess noise ratio of 6 dB with calibration data electronically stored and automatically downloaded to compatible analyzers, reducing user error and ensuring traceability.

Technical Specifications

• Frequency Range: 10 MHz to 18 GHz


• Excess Noise Ratio (ENR): 6 dB nominal; 4.5 to 6.5 dB range


• Noise Figure Measurement Capability: DUTs up to 20 dB


• Impedance Consistency: Reflection coefficient change between ON and OFF states < 0.01; reflection coefficient magnitude < 0.01 maintains uncertainty below 0.1 dB


• Standard Connector: APC-3.5 (male); Type-N (male) optional


• Weight: 1.5 kg


• Operating Temperature: 23°C ± 5°C (reference 23°C / 296 K)


• Warm-up Time Required: 60 minutes (analyzer specification)

Key Features

• Electronic storage of ENR calibration data with full traceability


• Automatic temperature measurement via internal thermometer


• Temperature compensation applied to calibration data for improved accuracy


• Automatic data download to compatible noise figure analyzers


• Electronically stored ENR uncertainty and reflection coefficient data at each frequency point


• Impedance stability minimizes gain variations in low-noise and impedance-sensitive DUTs

Typical Applications

• Noise figure measurement of low-noise amplifiers


• Characterization of GaAs FET devices and other gain-sensitive components


• System-level noise performance validation


• Automated noise figure measurements with integrated analyzer systems

Compatibility & Integration The N4000A integrates with Keysight NFA Series noise figure analyzers and Keysight ESA E-Series and X-Series signal analyzers for automated measurement and data transfer.