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We have evaluated a Josephson arbitrary waveform synthesizer (JAWS) in the voltage range from $1~\mu \text{V}$ to 1 mV at frequencies from 60 to 1000 Hz for the use in the calibration of lock-in amplifiers. The uncertainty contribution from the JAWS system is 45 nV for 1 mV at 1000 Hz and $k=2.0$. We anticipate that the JAWS will help extend the lower voltage and frequency range of ac voltage metrology and improve the uncertainties by one order of magnitude compared to conventional techniques. [ABSTRACT FROM AUTHOR]

We have developed a system to extend, by a factor of up to 1000, the voltage range over which Josephson arbitrary waveform synthesizers (JAWS) can be used in ac voltage metrology. The system is based on a precision inductive voltage divider, with a lock-in amplifier as the detector. Using a JAWS with a maximum output voltage of 250 mV (root mean square), we have made accurate voltage measurements up to 120 V at 60 Hz with expanded uncertainties ($k = 2$) of no more than 1.5 $\mu \text{V}$ /V and demonstrate that the system can operate up to 1 kHz. We anticipate that our JAWS-based system will improve uncertainties in ac voltage metrology by one order of magnitude compared to techniques based on thermal voltage converters. [ABSTRACT FROM AUTHOR]

We have developed a programmable Josephson voltage standard that can generate voltages up to 20 V with a resolution of 10 nV. The standard has two superconductor–normal metal-superconductor junction arrays connected in series and driven by two radio frequency oscillators. The standard has been integrated into a digital voltmeter calibration system for voltages from 10 nV up to 1000 V. The expanded uncertainty (k = 2) of the system is approximately 10 nV for voltages up to 20 V and 0.9 \mu\V/V in the voltage range from 20 to 1000 V. [ABSTRACT FROM PUBLISHER]

Measurements of the ac–dc difference of a thermal converter have been performed using a Josephson waveform synthesizer and a precision buffer amplifier at frequencies from 10 Hz to 4 kHz, showing agreement with conventional standards of better than 1 \mu\V/V up to 1 kHz. In addition, a method of finding the operating parameters of the programmable Josephson array that corresponds to minimal uncertainty is discussed. [ABSTRACT FROM PUBLISHER]

A system designed for precision measurement of ac–dc difference of thermal voltage converters in terms of a programmable Josephson voltage standard is under development at the National Measurement Institute, Australia, in collaboration with the National Institute of Advanced Industrial Science and Technology, Japan. The agreement between the new system and calculable thermal converters is presently better than 0.5 \mu\V/V at frequencies up to 40 Hz and voltages up to 0.75 V. [ABSTRACT FROM AUTHOR]

This paper describes a standard for traceable measurements of electrical power of sinusoidal signals at voltages up to 1000 V, currents up to 20 A, and frequencies from 40 Hz to 200 kHz. The standard uses thermoelectric effects to relate the alternating power to that of known dc signals. It is comprised of a thermal power comparator, inductive and resistive voltage dividers, and a range of wideband current shunts. The performance of each of the components has been evaluated through traceable measurements in terms of fundamental standards. The paper presents the design of the system and its components, evaluation techniques, and measurement uncertainties. [ABSTRACT FROM AUTHOR]

This paper presents a new realization of standards for ac-dc difference at voltages ranging from 1 to 4 V and frequencies of up to 1 MHz. This work has mainly been focused on improving the determination of the components of ac-dc difference that most significantly contributed to the uncertainty of the previous realization. These components are the ac-dc difference due to skin effect, transmission line effect, and the interaction between parasitic inductances and capacitances, which is described here as the LIC effect. As a result, combined 1 - σ uncertainties as low as 4.3 μV/V at 1 MHz have been achieved. [ABSTRACT FROM AUTHOR]