Calibration at Disney World
NCSL International Workshop and Symposium, Orlando, FL, August 3–7, www.ncsli.org.
-- Test & Measurement World, 10/1/2008
The 2008 NCSLI symposium began with a keynote address by Dr. Richard S. Davis with the International Bureau of Weights and Measures. Davis explained why the kilogram, the last standard of the International System of Units, is still an artifact. “It’s only a matter of time until we redefine the kilogram,” he said.
In a technical session, Dean Jarrett of NIST (National Institute of Standards and Technology) discussed measurement methods and NIST traceability paths for high-resistance measurements. He showed a measurement system that lets a primary standards lab use a teraohmmeter to transfer resistance from NIST. George Jones of NIST discussed power loading of 1-Ω resistance standards. He found that reference resistors were producing different values depending on the excitation current.
Paul Roberts of Fluke explained how phase noise affects the calibration of RF spectrum analyzers. He discussed how the different components of a spectrum analyzer contribute to overall noise as you move away from a carrier.
Dr. Li Pi Su from the US Army Primary Standards Lab reported on a comparison of vector network analyzer measurements conducted at the three primary standards laboratories of the US Department of Defense and two industry labs. The method involved calibrating four attenuators at frequencies from 1 GHz to 26.5 GHz.
Steven Stahley of Cummins discussed the construction of a new metrology lab. He cited issues with location, lab planning, and unforeseen circumstances in his presentation.
On the Exhibit FloorFluke showed an RF calibration system for spectrum analyzers for frequencies above and below 4 GHz. The company’s Hart Scientific division exhibited blackbody sources for calibrating infrared thermometers. Keithley Instruments exhibited the 2636 SourceMeter, for low-current, high-resistance measurements, and its latest bench multimeter, the 6½-digit Model 2100. Yokogawa exhibited the DL9140L 1-GHz oscilloscope.
Agilent Technologies demonstrated its precision network analyzer, the E4448, used as a calibrator for RF devices such as attenuators. Ametek displayed a dry-well calibrator with a temperature range of –90° C to 650° C that works with an eight-channel probe scanner.
