The Weinschel / Tegam 1806 is designed for use with bolometer elements to measure high frequency or microwave power from 10W to 30 mW. Model 1806 also functions as a standard for the calibration of bolometers mounts, detectors, RF voltmeters, and for precision insertion loss measurements when used with the System IIA, automatic power meter calibration system. The 1806 features: 0.03% +2ToneW typical power measurement accuracy, .003% substitution bridge accuracy, includes two type IV power meters & two built in temperature controllers for use with bolometer mounts (including HP Temperature Compensated Thermistor Mounts with cable P/N 138-652), rack mountable. Applications: RF Calibration Labs, used with System IIA to calibrate a wide variety of Tegam, Gigatronics, HP, and other brands of RF power sensors and thermistor mounts. Precision low level power measurement.