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A Voltage Calibrator based on a 10-V programmable Josephson Array that is simple to use, provides DC and AC calibration up to kHz range for industry-common equipment, and ensures direct traceability to a quantum-based standard, is under development. This device has proven to excel conventional DC standard systems and will extend into low frequency AC range, thereby making itself a practical and robust...
This paper presents the results of using two different types of a null detector, a lock-in amplifier and a digital sampling voltmeter, to measure the difference between a sinusoidal and a stepwise approximated AC voltage generated by means of a programmable Josephson voltage standard. Preliminary results of ac-dc difference measurement made on a thermal converter using the two null detectors agree...
This paper describes a new experimental set-up, based on a double Josephson waveform synthesizer for high precision ac-dc transfer measurements. A detailed description of the experimental set-up and the first results are presented.
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 μV/V. Also discussed is a method of finding the operating parameters of the programmable Josephson array that correspond to minimal uncertainty.
This work presents an improved and much more flexible setup of the dual Josephson voltage standard potentiometer. It can be used for high precision arbitrary resistance ratio measurements. For this purpose a 18 channel DAC based current source was developed to control all segments of binary divided 1-V Josephson voltage standard arrays. Additionally different types of current sources to generate the...
This article proposes a way for increasing the accuracy of calculable AC voltages from an AC-Programmable Josephson Voltage Standard (AC-PJVS). Combining meander-like waveforms reduces difficulties concerning transients, source instabilities and non-sinusoidal waveforms. Thus uncertainties of an AC-PJVS can be reduced.
We are implementing a new standard for 60 Hz power measurements based on precision sinusoidal reference voltages from two independent programmable Josephson voltage standards (PJVS): one for voltage and one for current. The National Institute of Standards and Technology PJVS systems use series arrays of Josephson junctions to produce accurate quantum-based DC voltages. Using stepwise-approximation...
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