Direct comparison of the NRC hysteretic and the NRC watt balance Programmable Josephson Voltage Systems

At the National Research Council in Ottawa, the conventional Hysteretic Josephson Array Voltage System (HJVS) and the Programmable Josephson Array Voltage System (PJVS) associated with the watt balance experiment have been directly compared. This direct comparison of Josephson array systems uses an improved automated biasing technique for the hysteretic array. The comparison is being performed with different nanovoltmeters including the unique detector associated with the watt balance experiment. Noise, stability and linearity of the detectors are examined. Preliminary results indicate that the two Josephson systems, under optimized conditions, agree within (0.09 Ñ 0.54) nV at the nominal level of 1 V.