The Keysight N8487S is a balance thermocouple power sensor engineered for precision RF power measurements from DC to 50 GHz. Built on dual thermopile power detectors integrated on a single chip, this sensor employs RF to DC thermoelectric substitution measurement for high accuracy and metrological traceability. It serves as a measurement standard in microcalorimeter-based primary systems and as a secondary or reference standard across demanding applications.
Technical Specifications
• Frequency Range: DC to 50 GHz
• Power Measurement Range: −35 dBm to +20 dBm
• Measurement Method: RF to DC thermoelectric substitution
• Sensitivity (RF Connector at 25 °C): 1080 mV/W
• Reflection Coefficient Magnitude: <0.2 across operating frequency range (50 Ω reference)
• Load Resistance (Coaxial Connector): 50.9 Ω typical
• DC Heater Resistance: 50.1 Ω
• Thermocouple Resistance (Dual, RF and DC): 17.1 Ω
• SWR (Typical): 1.05 DC–2 GHz | 1.09 above 2–12.4 GHz | 1.11 above 12.4–18 GHz
• Maximum Input RF Power (CW): 316 mW (+25 dBm at 50 Ω)
• Power Linearity: <0.55% (−1 to +15 dBm) | <0.80% (+15 to +30 dBm)
• Zero Set: <25 nW
• Zero Drift: <10 nW
• Measurement Noise: <80 nW
• Calibration Factor Uncertainty: ±1.10% at 14.0 GHz (25 ± 3 °C) | ±2.60% at 30.0 GHz (0–+55 °C)
– Key Features
• Dual thermopile architecture for stability across temperature and time
• EEPROM stores calibration factors, eliminating manual entry
• 2.4 mm male connector interface
• Wide impedance compatibility from 50 Ω to 2 kΩ DC resistance range
– Typical Applications
• Primary measurement standards in microcalorimeter-based systems
• Secondary and reference standards in RF power characterization
• Broadband power measurement from DC through millimeter-wave frequencies
– Compatibility & Integration
Backward compatible with Agilent P-Series, EPM-P Series, and EPM Series power meters. Supports SCPI codes compatible with 8480 Series (Option CFT) and E-Series sensors.
