Automatic RF voltage calibration with a primary voltage standard up to 1 GHz

An automatic system for the calibration of RF voltage transfer standards in the frequency range between 1 MHz and 1 GHz is described. It incorporates a coaxial dual dry-load calorimeter as a primary voltage standard, with an automated computer-controlled DC voltage balance. By means of comparison measurements with a thermal voltage converter, the estimated relative uncertainties (2 sigma ) for frequencies between 1 MHz and 100 MHz have been reduced by a factor of two to values between 0.01% and 0.1%. >