A QHE-based system for calibrating impedance standards

Coaxial transformer bridges applied to a newly formed system for calibrating impedance standards are described. In this system, an R-R bridge characterizes reference quantum Hall devices as well as directly links them to 12906.4 /spl Omega/ or 10000 /spl Omega/ standard resistors. These resistors, in turn, serve as reference standards in capacitance calibrations made by a multifrequency quadrature R-C bridge and a C-C bridge. Finally, by means of a multifrequency double-balance L bridge, 1- and 10-nF capacitors calibrated in this manner are linked to inductance standards whose values range from 1 to 100 mH.