A three-way, on-site comparison of the 10 V-Josephson voltage standards of the PTB, the SP and the BIPM

Comparisons of the 10 V Josephson array voltage standard (JAVS) of the Bureau International des Poids et Mesures (BIPM) were made at the Physikalisch-Technische Bundesansalt (PTB), Braunschweig, Germany with those of the PTB and of the Swedish National Testing and Research Institute (SP), Boras, Sweden, in January 1998. Although the results agree within an overall uncertainty of less than 1 part in 10/sup 9/, a small, but interesting, dependence on microwave power was observed in the DC output of one array.