Agilent/Keysight 8481B

The Agilent/Keysight 8481B is a coaxial thermocouple power sensor engineered for accurate average power measurements from 10 MHz to 18 GHz. This Type-N male connector sensor delivers power readings across 0 dBm to +44 dBm with less than 1% linearity error and extremely low SWR across its operating range, minimizing mismatch uncertainty in RF and microwave test systems.

Technical Specifications

• Frequency Range: 10 MHz to 18 GHz


• Power Measurement Range: 0 dBm to +44 dBm


• Power Linearity: Less than 1%


• Standing Wave Ratio (SWR): 1.40 (10–30 MHz), 1.18 (30–50 MHz), 1.10 (50 MHz–2 GHz), 1.18 (2–12.4 GHz), 1.28 (12.4–18 GHz)


• Temperature Coefficient: ±0.15%/°C (typical maximum, post-zeroing)


• Connector: Precision Type-N (male)


• Sensing Element: Thermocouple


• Calibration: NIST-traceable with on-board calibration port for temperature and meter variation compensation


• Signal Compatibility: CW and pulsed signals

Key Features

• EEPROM stores calibration factors, eliminating manual coefficient entry


• Embedded calibration port reduces uncertainties from thermal drift and sensor/meter variations


• Consistent performance across the 10 MHz to 18 GHz spectrum with controlled SWR behavior

Typical Applications

• Average power measurement in RF and microwave systems


• CW and pulsed signal characterization


• Power meter validation and system calibration

Compatibility & Integration The 8481B integrates with Agilent and Keysight power meters including the EPM series (E4418B, E4419B), EPM-P series (E4416A, E4417A), 70100A, E1416A VXI power meter, and legacy 43X series models (435B, 436A, 437B, 438A). The sensor's automated calibration data transfer via EEPROM simplifies multi-meter deployment.