Progress on the New NMIA Calculable Cross-Capacitor

A new calculable cross-capacitor and associated impedance measurement chain is being built at the National Measurement Institute Australia (NMIA). The new system is intended to reduce the uncertainty of the farad as realised by a calculable capacitor to a few parts in 10
⁹
, an order of magnitude improvement on existing calculable capacitor systems. We report here on recent progress on the assembly of the calculable capacitor, specifically the measurement of the frequency dependent correction, and the final alignment of the electrodes.