Keysight (Agilent) 8485D 50 MHz – 26.5 GHz,RF Power Sensor

The Keysight 8485D is a diode power sensor engineered for precise average power measurements spanning 50 MHz to 26.5 GHz. Operating across a -70 dBm to -20 dBm dynamic range (50 dB), this 50 Ohm sensor delivers the measurement accuracy and traceability demanded in RF and microwave characterization. Its diode sensing element and excellent SWR minimize mismatch uncertainty, critical in broadband power assessment applications.

Technical Specifications

• Frequency Range: 50 MHz to 26.5 GHz (50 MHz to 33 GHz with Option 8485D-033)


• Power Measurement Range: -70 dBm to -20 dBm (100 pW to 10 µW)


• Dynamic Range: 50 dB


• Impedance: 50 Ohm


• Connector: 3.5 mm male


• Measurement Type: Average power


• Calibration: NIST traceable; includes Keysight 11708A 30 dB attenuator calibrated to 0 dBm at 50 MHz

Key Features

• Diode power sensing element for fast, reliable response


• Excellent SWR reduces mismatch-induced measurement error


• 50 dB dynamic range accommodates weak and moderate signal levels


• NIST calibration and traceability ensure metrological confidence


• Supplied with precision 30 dB attenuator for reference calibration


• Extended-frequency option reaches 33 GHz

Typical Applications

• RF and microwave power characterization


• Average power measurement in broadband systems


• Signal chain validation and component testing


• Calibration and verification of power measurement setups

Compatibility & Integration The 8485D connects to Keysight EPM Series (N1913A/14A, E4418B/19B), EPM-P Series (E4416A/17A), P-Series (N1911A/12A), and E1416A VXI power meters. Legacy support includes 70100A and 43X series instruments. The 3.5 mm connector ensures standard RF connectivity.