Accurate RF Voltage Measurements Using a Sampling Voltage Tracker

The rf voltage measurement capability of an equivalent time sampling system is described. The frequency range investigated is 1 to 100 NHz. Over this range, the measured errors, determined by ac/dc thermal transfer, are within the stated uncertainties presently provided by NBS for thermal converter calibrations. The system offers several advantages over conventional thermal transfer techniques: ac/dc transfers are not required, loading and transmission line problems are reduced, and direct measurement of voltages from 2 V to as low as 10 mV are possible.