APMP International Comparison of AC–DC Transfer Standards at the Lowest Attainable Level of Uncertainty

Direct comparison of a 1 V Josephson arbitrary waveform synthesizer and an ac quantum voltmeter

“…This result is an improvement from previous comparisons by one order of magnitude [21] and also better as in a previous on-chip comparison at a lower voltage level [17]. We have further demonstrated that the quantum accuracy of the 1 V RMS JAWS is about one order of magnitude better than conventional ac-dc transfer standards [13,14]. In addition, the comparison establishes the potential of the ac-QVM for measuring ac voltages with an uncertainty of 10 −8 (k = 1) for frequencies up to 500 Hz.…”

“…for ac-dc transfer measurements [5][6][7][8][9] and for calibrating ac voltage standards and instruments [10][11][12]. The increase to the 1 V level is important for many metrological applications, as instruments and measurement methods are consequently more accurate in that range [13][14][15][16].…”

Technique for the calibration of thermal voltage converters using a Josephson waveform synthesizer and a transconductance amplifier

“…The best TCs have finite but stable ac-dc differences that have been evaluated, using various techniques, with uncertainties better than 1 μV V −1 (k = 2) (Klonz et al 1995b, Budovsky andInglis 2001). Uncertainties as low as 0.4 μV V −1 at frequencies from 40 Hz to 10 kHz have been confirmed by several international comparisons, as reported for example in Klonz (2002) and Budovsky et al (2005). Various low-and high-frequency effects increase the uncertainties at frequencies outside of this range, which has also been confirmed by the aforementioned comparisons.…”

“…Therefore, means must be provided to unload the array. Measurements have been performed when driving the TC with additional current sources (Behr et al 2005), another Josephson array (Djordjevic et al 2010) and a precision buffer amplifier (Budovsky andHagen 2010, Séron et al 2012). In this paper, we present an alternative set-up that uses a transconductance amplifier (TCA); see Budovsky et al (2012).…”

Calibration Process Quantity Reduction of the Thermal Voltage Converter Standard using a Three-stage Build-up and Build-down Method

“…Following Budovsky's (2002) method, the measurements were conducted sequentially five times (n = 5), where each sequence consisted of three measurement variables, namely AC, DC+, and DC-. A type A measurement uncertainty due to random error emerged (Table 5) Based on Equation 4, the AC-DC differences for the six formations at certain operating frequencies are presented in Table 3.…”