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A reevaluation of the NIST low-frequency standards for AC-DC difference in the voltage range 0.6-100 V

T.E. Lipe
1996 IEEE Transactions on Instrumentation and Measurement  
A reevaluation of the NIST standards of ac-dc difference was undertaken in an effort to reduce the calibration uncertainty offered by NIST for thermal voltage converters (TVC's) at frequencies bellow 100  ...  This reevaluation of the NIST low-frequency standards will permit a significant reduction in uncertainty for ac-dc difference calibrations at 10 Hz in the voltage range from 0.6-100 V.  ...  Zhang, Statistical Engineering Division, NIST, for advice on the statistical aspects of this work.  ... 
doi:10.1109/19.543985 fatcat:rkkimgwc5jcabmvjfmp5y4stzy

CCE intercomparison of AC-DC transfer standards

J.P.M. de Vreede
1993 IEEE Transactions on Instrumentation and Measurement  
A worldwide intercomparison is described covering both ac voltage and ac current measurements in the frequency range from 40 Hz to 1 MHz.  ...  Results are consistent within 10-20 ppm at low voltage and frequency, but differ by up to 100 ppm at high voltage and frequency.  ...  From the data obtained in this intercomparison it seems that ac-dc transfer measurements for voltage are in agreement to within some 10 ppm for the lower ranges (up to 100 V) and within the audio range  ... 
doi:10.1109/19.278530 fatcat:bai3oe6qx5bfdgqdxw4biqyxf4

Uncertainty analysis for ac-dc difference measurements with the AC Josephson Voltage Standard

Jason M Underwood
2018 Metrologia  
For audio frequencies and for voltages less than 200 mV, ac-dc transfers with the ACJVS may reduce the combined uncertainty by factors of 2 to 10, compared with conventional methods based on thermal converters  ...  In agreement with earlier work, the transmission line is the primary contributor to Type B errors for frequencies above 10 kHz.  ...  Acknowledgments The author would like to thank T. Lipe, N. Shattuck, and S. Cular for valuable discussions related to ac-dc difference, B. Waltrip and N.  ... 
pmid:32863435 pmcid:PMC7450763 fatcat:fcq2tge7lja7lp3hb5af6if24y

News briefs

1990 Journal of Research of the National Institute of Standards and Technology  
The NIST instrument also can be used to evaluate thermal voltage converter-based measurement systems and for on-line ac voltage calibration of automatic test equipment.  ...  AC VOLTAGE LABORATORY INTERCOM-PARISON TESTS CONDUCTED USING NIST-DEVELOPED DSS NIST scientists recently conducted an ac voltage intercomparison to determine the consistency of ac voltage measurements  ...  NIST TEST SYSTEM PROVIDES NEW CAPABILITIES FOR NONDESTRUCTIVE EVALUATION OF POWER TRANSISTORS A new NIST nondestructive test system for power transistors that can accommodate up to 100 A and switch up  ... 
doi:10.6028/jres.095.0010 fatcat:q4xtye4zi5crtfzof2rltww3ba

2019 Index IEEE Transactions on Instrumentation and Measurement Vol. 68

2019 IEEE Transactions on Instrumentation and Measurement  
., +, TIM June 2019 2041-2046 Toward a Calculable Standard Shunt for Current Measurements at 10 A and Up To 1 MHz.  ...  ., +, The ACE1 Electrical Impedance Tomography System for Thoracic Imaging. Realization of Absolute Phase and AC Resistance of Current Shunts by Ratio Measurements.  ...  Image scanners Nonlinear Reconstruction of Multilayer Media in Scanning Microwave Microscopy. Wei, Z., +, TIM Jan. 2019 197-205  ... 
doi:10.1109/tim.2019.2956662 fatcat:kotlu7gwcngrdkelerc5va2hqe

Bolometric voltage and current (bolovac) standard for high and microwave frequencies

M.C. Selby
1968 Journal of Research of the National Bureau of Standards Section C Engineering and Instrumentation  
A sta ndard of voltages a nd c urre nts for lumped-co nstant, coaxial, a nd other circ uits operating in the TEM mode ha s bee n developed.  ...  Schematic diagram showing the applications of the Bolovae for (a) voltage standardization, and (b) current standardization.  ...  Bo lovac set up to calibrate ATVM. FI GU RE 9j.  ... 
doi:10.6028/jres.072c.006 fatcat:4u4l55jjhjgjzewglus7x6ja2u

Bolovac application for HF and microwave power measurement and standardization

M.C. Selby
1970 Journal of Research of the National Bureau of Standards Section C Engineering and Instrumentation  
Th e bolom e tric voltage a nd c urre nt (BOLOYAC) sta ndard fo r frequ e nc ies to 18 GHz and higher, recen tl y deve loped a t th e Nationa l Burea u of Sta ndard s (N BS), ca n a lso be used to meas  ...  ure power, offe rin g th e fo ll ow ing a dvantages ove r a n umbe r of other me th od s in use toda y: Key W ord s : Bo lometric power standards; Bolovac power measure me nts; ca lib rati on of power  ...  Similar calibration te rms are measured for feedthrough type meters with the same uncertainties for frequencies to 4 GHz and ± 2 to 3 percent for higher frequencies.  ... 
doi:10.6028/jres.074c.015 fatcat:gff22tgb6bdxrokfxnrh7omtla

News Briefs

1999 Journal of Research of the National Institute of Standards and Technology  
Presently, the NIST calibration service for determining the ac-dc difference of current shunts is limited to current levels up to 20 A at frequencies up to 100 kHz.  ...  The new shunt will act as a NIST standard for calibrating shunts and current transformers at current levels up to 100 A and frequencies up to at least 10 kHz as a NIST special test.  ...  Purpose: To provide advice and assistance on measurement and calibration problems, tracing to NIST the accuracies of measurement standards needed for research work, factory production, or field evaluation  ... 
doi:10.6028/jres.104.008 fatcat:3hpmprvyufgt5hlid6i6dcbk4a

News Briefs

1998 Journal of Research of the National Institute of Standards and Technology  
Poids et IEEE STANDARD DEFINITIONS FOR TIME AND FREQUENCY NIST staff in Boulder, CO have played a key role in the revision of IEEE Standard 1139-1988, Standard Definitions of Physical Quantities for Fundamental  ...  overlapped measurements. 117 provides the basis for specifications and acceptance testing for clocks, oscillators, and a range of other equipment used in timing applications and low-phase-noise systems  ...  FIRST AC-DC TRANSFERS ACHIEVED AT CRYOGENIC TEMPERATURES To investigate the feasibility of making ac-dc difference calibration-level measurements at cryogenic temperatures, a team of NIST researchers has  ... 
doi:10.6028/jres.103.007 fatcat:eimjgj64vrgqroqwehnknsccaa

2020 Index IEEE Transactions on Instrumentation and Measurement Vol. 69

2020 IEEE Transactions on Instrumentation and Measurement  
Meenalochani, M., and Sudha, S., Influence of Received Signal Strength on Prediction of Cluster Head and Number of Rounds; TIM June 2020 3739-3749 Hendeby, G., see Kasebzadeh, P., TIM Aug. 2020 5862  ...  Converter Using All-Digital Nested Delay-Locked Loops With 50-ps Resolution and High Throughput for LiDAR TIM Nov. 2020 9262-9271 Helsen, J., see Huchel, L., TIM July 2020 4145-4153 Hemavathi, N.,  ...  ., +, TIM July 2020 4476-4486 Reference Load for Power Analyzer Phase Adjustment and Calibration up to 150 kHz.  ... 
doi:10.1109/tim.2020.3042348 fatcat:a5f4fsqs45fbbetre6zwsg3dly

News Briefs

1997 Journal of Research of the National Institute of Standards and Technology  
The system offers continuous frequency coverage of the complete band, that includes satellite communications among other applications, and provides the basis for a new measurement service responding to  ...  System design is similar to that of existing NIST waveguide systems covering the WR-62 (12.4 GHz to 18 GHz) and WR-42 (18 GHz to 26.5 GHz) bands. It is 596  ...  Live audio and video provided feedback for real-time confirmation of remote command execution.  ... 
doi:10.6028/jres.102.042 fatcat:xm36nbly5rcxtbky3h56kwg2x4

Transverse single-particle instability in the NAL 500 GeV accelerator

R. Stiening, E.J.N. Wilson
1974 Nuclear Instruments and Methods  
The present RF system will be replaced with one of seven times the frequency and capable of providing accelerating voltages up to 7 MeV/turn.  ...  A s one expects, the beam is a strong source of radio frequency signals up to at least the 100th harmonic of its revolution frequency.  ...  T h e r e ' s also a time-out so that if you fail to get a reply at all, it won't hang up; it will give you an e r r o r bit in the system and f o r that type of problem, it's worked out very well.  ... 
doi:10.1016/0029-554x(74)90076-7 fatcat:n5rwx4ginngghj4ebwkpsqu754

The Expedition of the Research Vessel "Polarstern" to the Antarctic in 2008 (ANT-XXIV/3) Edited by

Eberhard Fahrbach, Hein De Baar
2010 unpublished
Acknowledgements The authors would like to show their deep thanks and appreciation to the officers and crew of Polarstern, for all their efforts in helping us throughout the duration of ANT-XXIV/3.  ...  Acknowledgments The authors would like to show their deep thanks and appreciation to the crew of the Polarstern, for all their efforts in helping us throughout ANT-XXIV/3.  ...  This was the strategy of choice for intercomparison of CO 2 system measurements, which had already been calibrated routinely on both ships by the shipboard use of certified reference material (CRM, supplied  ... 
fatcat:wasgbf4pbvfsbootnqycilk7g4