Evaluation of frequency performance of resistance standards

A set of reference resistors with calculable frequency performance has been realized and is available for precision measurements of frequency dependences of resistance standards, as well as for characterization tests of quantum Hall devices. Thanks to their multifilar designs, these resistors are of reasonable dimensions even for resistance values higher than 10,000 /spl Omega/. A transformer bridge has been developed for precision comparisons of the reference resistors with conventional four terminal-pair resistance standards or quantum Hall devices in a frequency range up to 5 kHz. Correctness of the mathematical models used in calculating the frequency dependences of the reference resistors has been proved by international comparisons in the framework of an EUROMET project.