Title :
Frequency dependence of some 100 /spl Omega/ resistors measured with a CCC-based AC resistance bridge
Author :
Seppa, H. ; Satrapinski, A. ; Varpula, T. ; Saari, J.-M.
Author_Institution :
VTT Autom., Tech. Res. Centre of Finland, Finland
fDate :
June 27 1994-July 1 1994
Abstract :
The paper describes frequency dependence of some 100 /spl Omega/ standard resistors in the frequency range from 0.1 Hz to 1 Hz. The measurements are carried out with an automated ac bridge based on the cryogenic current comparator (CCC) and a dc SQUID null detector. A GaAs quantum-Hall resistance cooled down to 1.4 K-1.8 K was used as a reference. The plateau i=2 was obtained at 7.5 T. Some resistors such as a N.B.S. type 100 /spl Omega/ (L&N) reveal a strong frequency dependence below 1 Hz while the frequency dependence of the Wilkins type 100 /spl Omega/ (Tinsley) is barely visible.<>
Keywords :
bridge circuits; bridge instruments; comparators (circuits); electric resistance measurement; low-temperature techniques; measurement standards; resistors; 0.1 to 1 Hz; 1.4 to 1.8 K; 100 /spl Omega/ standard resistors; 100 ohm; 7.5 T; DC SQUID null detector; GaAs; GaAs quantum-Hall resistance; NBS type; Tinsley; Wilkins type; automated AC resistance bridge; cryogenic current comparator; frequency dependence; reference; Bridges; Cryogenics; Current measurement; Detectors; Electrical resistance measurement; Frequency dependence; Frequency measurement; Measurement standards; Resistors; SQUIDs;
Conference_Titel :
Precision Electromagnetic Measurements, 1994. Digest., 1994 Conference on
Conference_Location :
Boulder, CO, USA
Print_ISBN :
0-7803-1984-2
DOI :
10.1109/CPEM.1994.333259
