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Comparison of the NIST and NRC Josephson Voltage Standards (SIM.EM.BIPM-K10.b)



Yi-hua Tang, Barry Wood


A comparison between the National Institute of Standards and Technology (NIST) and the National Research Council (NRC) Josephson Voltage Standards (JVS) was carried out at NRC from August 13 to August 17, 2007.  The comparison was made at the 10 V level. It was a two-way direct JVS comparison, which means that the NIST JVS provided a voltage at 10 V and was measured against the NRC JVS with NRC's measuring system (hardware and software). The comparison was repeated by using the NIST JVS measuring system to measure a voltage at 10 V provided by the NRC JVS. The results from the two comparisons were consistent. The difference between the NIST CJVS and the NRC JVS is -0.28 nV with an expanded uncertainty (k = 2) 2.07 nV at 10 V or 2.07 parts in 10^10.
BIPM Key Comparison database (KCDB)


Tang, Y. and Wood, B. (2008), Comparison of the NIST and NRC Josephson Voltage Standards (SIM.EM.BIPM-K10.b), BIPM Key Comparison database (KCDB), [online],, (Accessed April 19, 2024)
Created July 1, 2008, Updated February 17, 2017