The Agilent Q8486A thermocouple power sensor is designed for use with the EPM series, EPM-P series, 70100A, E1416A and the discontinued 43x power meters, and provides excellent accuracy and stability. A 50 MHz calibration port is included with the power sensor for calibration which is traceable to the U.S. National Institute of Standards and Technology (NIST). This calibration eliminates the uncertainties due to temperature changes and the variance in making measurements with different meter/sensor combinations.