Agilent/Keysight U8485A

The Keysight U8485A is a USB thermocouple power sensor that delivers precise average power measurements across a broad frequency spectrum. It connects directly to a PC or USB-enabled Keysight instruments without requiring external power meters or supplies, drawing power directly from the USB port. Built on the proven front-end architecture of Keysight's legacy 8480 and N8480 series sensors, the U8485A adds USB connectivity and enhanced performance metrics for field and bench applications.

Technical Specifications

• Frequency Range: 10 MHz to 33 GHz (standard); DC to 33 GHz with Option -200 (DC coupled)


• Power Range: −35 dBm to +20 dBm


• Linearity: Less than 0.8%


• Measurement Speed: Up to 900 readings/second in free run/fast buffer mode


• Measurement Uncertainty: Real-time MU calculation capability


• Calibration: NIST or NPL traceability; internal calibration function for reduced setup time


• Connector: 3.5 mm (f) to N-Type (m) adapter supplied

Key Features

• S-parameter and gamma correction support


• Integrated DC reference source for internal calibration


• Built-in trigger input via standard BNC to SMB connection


• Compact, portable form factor with flexible cable options: 5 ft (1.5 m) standard; 10 ft (3 m) and 16.3 ft (5 m) optional lengths


• DC measurement capability for signal source and network analyzer calibration

Typical Applications

• Power reference standards and source power calibration


• EMC testing and compliance measurement


• Continuous average power monitoring across DC to 33 GHz range

Compatibility & Integration The U8485A integrates with Keysight BenchVue software (BV0007B) for instrument control and automated test sequences without programming. Compatible with Keysight EPM power meters (N1913B/14B and N1913A/14A), PNA/PNA-L/PNA-X network analyzers, FieldFox RF analyzers, and MXG signal generators for source power calibration workflows.