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Construction of a Large Transverse Electromagnetic Cell

Description: Report issued by the U.S. National Bureau of Standards discussing the construction of large electromagnetic cells. As stated in the introduction, "this instruction provides information and procedures necessary to fabricate a large transverse electromagnetic (TEM) cell to be used for experimental "electromagnetic interference" (EMI) evaluation studies" (p. 1). This report includes illustrations, and photographs.
Date: February 1979
Creator: Decker, W. F. & Wilson, W. A.
Partner: UNT Libraries Government Documents Department
open access

Electromagnetic Compatibility and Interference Metrology

Description: From abstract: The material included in this report is intended for a short course on electromagnetic compatibility/interference (EMC/EMI) metrology to be offered jointly by the staff of the Fields Characterization Group (723.03) and the Interference Characterization Group (723.04) of the Electromagnetic Fields Division (723). The purpose of this short course is to present a review of some of the radiated EMC/EMI measurement methods, to which the National Bureau of Standards (NBS) at Boulder, C… more
Date: July 1986
Creator: Ma, Mark T. & Kanda, M.
Partner: UNT Libraries Government Documents Department
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Linear Gain: Standard Antennas Below 1000 MHz

Description: Abstract: Gain and antenna parameters related to input impedance are calculated using a computer program called HVD6. This program uses well documented equations to compute these parameters for gain-standard antennas used in relative-gain or gain-transfer measurements at frequencies below 1000 MHz. The utility of this program is that it calculates gain patterns and input impedances for linear dipoles above perfect or imperfectly conducting plane ground and in free space, and for monopoles on pe… more
Date: May 1986
Creator: FitzGerrell, R. G.
Partner: UNT Libraries Government Documents Department
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Interactive FORTRAN Programs for Micro Computers to Calculate the Thermophysical Properties of Twelve Fluids (MIPROPS)

Description: From abstract: The thermophysical and transport properties of selected fluids have been programmed in FORTRAN 77 which is available for micro computers. The input variables are any two of P, p, T (pressure, density, and temperature) in the single phase regions, and either P or T for the saturated liquid or vapor states. The output is pressure, density, temperature, internal energy, enthalpy, entropy, specific heat capacities (Cp and Cv), speed of sound and, in most cases, viscosity, thermal con… more
Date: May 1986
Creator: McCarty, Robert D.
Partner: UNT Libraries Government Documents Department
open access

Design of the National Bureau of Standards Isotropic Magnetic Field Meter (MFM-10) 300 kHz to 100 MHz

Description: From introduction: In this report the following will he discussed: (1) design consideration of the broadband magnetic field sensor, (2) overall design of the magnetic field meter, (3) performance of the meter, (4) calibration and operating procedures, (5) alignment and adjustment procedures, and (6) summary and conclusions.
Date: October 1985
Creator: Cruz, J. E.; Driver, L. D. & Kanda, Motohisa
Partner: UNT Libraries Government Documents Department
open access

Fitness-for-Service Criteria for Assessing the Significance of Fatigue Cracks in Offshore Structure

Description: Abstract: Results of a research program to develop fitness-for-service criteria for assessing the significance of fatigue cracks in offshore structures are presented in five papers. Each paper describes the goals and approaches to a specific task and details the results of the study.
Date: August 1985
Creator: Cheng, Yi-Wen
Partner: UNT Libraries Government Documents Department
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An Electric and Magnetic Field Sensor for Simultaneous Electromagnetic Near-Field Measurements -- Theory

Description: Abstract: This paper describes the theory of a single sensor to perform simultaneous electric and magnetic near-field measurements. The theory indicates that it is possible to obtain the magnetic-loop and electric-dipole currents using a loop terminated with identical loads at diametrically opposite points. The theory also indicates that it is possible to obtain an ideal load impedance for achieving equal electric and magnetic field responses of the loop. Preliminary experiments have been perfo… more
Date: April 1983
Creator: Kanda, Motohisa
Partner: UNT Libraries Government Documents Department
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A Coaxial Noise Standard for the 1 GHz to 12.4 GHz Frequency Range

Description: From introduction: This note describes the design and construction of a coaxial thermal noise standard. The standard is designed to operate at the boiling point of liquid nitrogen with a noise temperature accurate to t 1 K in the frequency range from 1 GHz to 12.4 GHz.
Date: 1984
Creator: Daywitt, William C.
Partner: UNT Libraries Government Documents Department
open access

Site Attenuation

Description: Abstract: Site attenuation is a measure of performance of an open test site used at frequencies below about 1 GHz for antenna calibration and equipment emission and susceptibility testing. These sites typically consist of a large, obstruction-free ground plane and the hemisphere above it. Site attenuation of an ideal site is calculated and compared to data measured using the 30 m by 60 m NBS ground screen.
Date: November 1985
Creator: FitzGerrell, R. G.
Partner: UNT Libraries Government Documents Department
open access

Small Aperture Analysis of the Dual TEM Cell and an Investigation of Test Object Scattering in a Single TEM Cell

Description: Introduction: Small aperture theory is used to investigate the dual TEM cell. Analyzing coupling through an empty versus a loaded aperture leads to a model of dual TEM cell shielding effectiveness measurements. Small obstacle scattering yields results for both the field perturbation and the change in a cell's transmission line characteristics due to the presence of a test object in a TEM cell. In each case, theoretical values are compared to experimental data.
Date: 1984
Creator: Wilson, Perry F. & Ma, Mark T.
Partner: UNT Libraries Government Documents Department
open access

Reference Flat Pulse Generator

Description: Introduction: A reference step-like pulse generator is described which has been developed at NBS. This generator can be used for accurately characterizing the step response of various kinds of trap ient recording equipment (oscilloscopes, waveform recorders, transient digitizers, etc.). Basic design principles are given as well as complete circuit diagrams and descriptions. An analysis of the output stage of the generator is presented together with the circuit models for developing a time-domai… more
Date: October 1983
Creator: Andrews, J. R.; Bell, B. A. & Baldwin, E. E.
Partner: UNT Libraries Government Documents Department
open access

Theory of Near-Field Phased Arrays for Electromagnetic Susceptibility Testing

Description: From introduction: The feasibility of using a near-field array for electromagnetic susceptibility testing is studied. The basic objective is to control the element weightings such that a plane wave is generated within the test volume. The basic theory is developed for arbitrary array geometries, and numerical results are obtained for finite planar arrays. A general near-field array synthesis technique is developed, and the technique minimizes the mean square error in the test volume while const… more
Date: February 1984
Creator: Hill, D. A.
Partner: UNT Libraries Government Documents Department
open access

VOR Calibration Services

Description: from Introduction: The National Bureau of Standards has designed, constructed, and evaluated a standard for the support of very-high-frequency omnidirectional range (VOR) air navigation aids. The standard consists of two instruments: (1) a digital waveform signal generator for the composite VOR audio waveform, and (2) a standard phasemeter based on time series analysis of this waveform. Experimental results, a statistical analysis of them, and the principal software listings are included.
Date: April 1985
Creator: Larsen, Neil T.; Vecchia, Dominic F. & Sugar, George R.
Partner: UNT Libraries Government Documents Department
open access

Picosecond Time Difference Measurements Utilizing CAMAC-Based ANSI/IEEE-488 Data Acquisition Hardware : Operating Manual IE3, Version 1.0

Description: Abstract: Automated time-difference measurements at the picosecond level have been achieved. The system described combines the best properties of three common methods: the single heterodyne measurement technique, the frequency divider, and the dual-mixer time-difference measurement system. This particular system combines two instrumentation standards, ANSI/IFEE-583 and ANSI/IEEE-488 with new, modular dual-mixer time-difference measurement hardware. The modular, standardized hardware together wi… more
Date: August 1983
Creator: Glaze, D. J. & Stein, S. R.
Partner: UNT Libraries Government Documents Department
open access

Shielded Balanced and Coaxial Transmission Lines: Parametric Measurements and Instrumentation Relevant to Signal Waveform Transmission in Digital Service

Description: Abstract: A method is presented for determining the impulse and step responses of a shielded cable using time domain terminal measurements and a physically based mathematical model for the transmission line properties of the cable. The method requires a computer controlled time domain measurement system and was implemented using the NBS Automatic Pulse Measurement System (APMS). Data are also developed for the frequency domain complex propagation function (attenuation and its related minimum-ph… more
Date: June 1981
Creator: Gans, William L. & Nahman, N. S.
Partner: UNT Libraries Government Documents Department
open access

Basic Tables for Chemical Analysis

Description: Abstract: Tables of important data for use in the analytical chemistry laboratory are provided. These tables contain information for use in gas chromatography, liquid chromatography, infrared and ultraviolet spectrophotometry, mass spectrometry, and wet chemical techniques. Tables relating to safe practice in the analytical laboratory are also included.
Date: April 1986
Creator: Bruno, Thomas J. & Svoronos, Paris D. N.
Partner: UNT Libraries Government Documents Department
open access

The Characterization of Optical Fiber Waveguides: A Bibliography with Abstracts, 1970-1980

Description: Abstract: This bibliography contains approximately 450 citations of papers concerning the characterization of optical fiber waveguides. Papers from scientific journals, trade journals and conferences are included along with book chapters. The citations of organized by parameter measured and measurement method. Where published abstracts are available they are included.
Date: June 1981
Creator: Day, G. W.
Partner: UNT Libraries Government Documents Department
open access

A Review of Supercritical Fluid Extraction

Description: Forward: The purpose of this report is to summarize the results obtained from a brief investigation of supercritical fluid extraction principles and applications. This study was one portion of a project funded by the U.S. Department of Energy, Office of Fossil Energy, contract nuriber DE-AI01076PR06010, in response to a preliminary proposal submitted by the authors. This report sometimes uses company trade naries to identify processes and patent holders. This usage implies no endorsement by HBS… more
Date: December 1983
Creator: Ely, James F. & Baker, Jolene K.
Partner: UNT Libraries Government Documents Department
open access

The Characteristics of Iris-Fed Millimeterwave Rectangular Microstrip Patch Antennas

Description: From introduction: The fabrication of various iris-fed millimeterwave rectangular microstrip patch antennas is described. A model is proposed to describe the iris-fed antenna. Irises ranging in size from 15 percent of the area of the patch to the fully open waveguide are used to couple energy into the antenna. Resonance of the antenna is observed to be insensitive to the size of the iris for irises up to 115 percent of the size of the patch. A study is also made of th? relationship of coupling … more
Date: October 1983
Creator: Greenlee, D. H.; Kanda, Motohisa & Chang, David C.
Partner: UNT Libraries Government Documents Department
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A Near-Field Array of Yagi-Uda Antennas for Electromagnetic Susceptibility Testing

Description: Abstract: In electromagnetic susceptibility testing of electronic equipment, the ideal incident field is a plane wave. To approximate this condition, a seven-element array of Yagi-Uda antennas has been constructed and tested at a frequency of 500 MHz. The element weightings are determined by a near-field synthesis technique which optimizes the uniformity of the field throughout a rectangular test volume in the near field of the array. The amplitude and phase of the electric field have been meas… more
Date: June 1985
Creator: Hill, David A. & Koepke, Galen H.
Partner: UNT Libraries Government Documents Department
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Tests of Commercial Densimeters for LNG Service

Description: Abstract: Densimeters for liquefied natural gas (LNG) from four manufacturers were tested in liquid methane and an LNG-like mixture of methane, propane, and nitrogen in the density reference system (DRS). The calibration and performance of one type tested for the first time are reported. The stability of the calibrations and performances of three densimeters of a type previously tested have been examined and are also reported here.
Date: June 1982
Creator: Siegwarth, J. D. & LaBrecque, J. F.
Partner: UNT Libraries Government Documents Department
open access

Tables of Industrial Gas Container Contents and Density for Oxygen, Argon, Nitrogen, Helium, and Hydrogen

Description: Abstract: Custody transfer tables are presented for oxygen, argon, nitrogen, helium, and hydrogen. The tables are based on standard reference data previously compiled by the National Bureau of Standards. Two sets of tables are provided for each fluid. Tables in engineering units cover the range -40 to 130*F with pressures from 100 to 10,000 prig. Tables in SI units (density versus pressure and temperature) cover the range 200 to 370 K with pressures from 0.5 to 70 MPa. The tables in engineering… more
Date: June 1985
Creator: Younglove, Ben A. & Olien, Neil A.
Partner: UNT Libraries Government Documents Department
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