HP 8484A / Agilent 8484A Power Sensor, -70 dBm to -20 dBm (0.1 nW to 10 uW) at 10 MHz to 18 GHz

The 8484A diode power sensor is designed for use with the EPM series, EPM-P series, 70100A, E1416A and the 435A/B, 436A, 437A/B, and 438A power meters. It is a high sensitivity sensor operating from 10 MHz to 18 GHz at power levels from -70 to -20 dBm. It provides exceptional accuracy and stability even if your test signal is subjected to multi-tone environments, modulated carriers, or carriers with high harmonics. You also get extremely low SWR and its traceable to the U.S. National Institute of Standards and Technology (NIST).