Direct Comparison Of Dc Josephson Voltage Standard And Programmable Josephson Voltage Standard Of Tubitak Ume

10 V programmable Josephson voltage standard (PJVS) has been setup at TUBITAK Ulusal Metroloji Enstitusu (UME), national metrology institute of Turkey. The PJVS has compared to 10 V DC Josephson Array Voltage Standard (JVS) of TUBITAK UME which is regularly used for the calibration of DC Voltage Standards and DC voltage meters since 1997. A direct comparison between two Josephson voltage standards was carried out at the level of 10 V in order to verify the accuracy of the PJVS. The difference between the two systems (JVS - PJVS) was +0.96 nV with an uncertainty of 2.4 parts in 10(-10) (k = 1).