A Standard for Checking High-Frequency Voltmeters

The design and the working parameters are described for a precision apparatus for measuring high-frequency voltages, together with an improved procedure for voltmeter checking.     

一种新型DC100A电流源标准的设计

介绍了一种利用最新研发的电子元件和电流检测技术设计的DC 100A直流电流标准装置.该标准采用"ZERO-FLUK"技术解决了电流采样单元的零温漂、零功耗问题;采用高分辨力数模转换控制电路解决了系统控制精度和稳定性的问题.     

The Compensated Current Comparator; A New Reference Standard for Current-Transformer Calibrations in Industry

The compensated current comparator combines in one device the high ratio accuracy of the three winding ratio transformer or current comparator with the energy-transfer properties of a normal current transformer. Its ratio error is very small and so independent of the energy-transfer function that it can be operated at very high burden. Even negative burdens may be imposed, and, when operated in this mode, the device fulfils the functions of a high-current primary supply transformer. As such, it is highly suited to in situ calibrations in industry. Construction details of a multiratio compensated current comparator, covering all normally encountered ratios from 5/5 to 1200/5, are given. Its ratio accuracy, for burdens up to 750 va, is better than five parts per million. A test set, for use in calibrating current transformers up to errors of one per cent and 100 minutes, is also described. The set employs three conductance and three capacitance decades, with a three-position range switch, and is direct reading.     

A New Device for Measurements of Pulses or High-Frequency Currents

Resistors are frequently used for measuring waveforms and magnitudes of pulse currents, assuming that the effect of residual inductance of the resistors is very small. However, when the very high-frequency components of the current must be taken into account, the effect of the residual inductance cannot be neglected. In this paper, a new current measuring device with a resistor of a special type is described. It is so constructed that the effect of residual inductance does not appear in the observing circuit of the device. Consequently, the voltage observed becomes exactly the product of the resistance of the device and the current to be measured, flowing through the device. As the effect of the residual inductance of the device does not appear in the observing circuit, the resistance of the device can be made very low, consequently, the circuit condition will be practically undisturbed by the connection of the device.     

新建立的衰减计量国家标准装置

为了满足大衰减量值的溯源，研制成功了新的PAS-1型衰减测量接收机和新的国家标准装置。文中论述了该标准装置的原理及特点，详细分析了它的不确定度。试验表明：该标准装置频带可扩展到18GHz，量程达100dB，在100dB量程的测量不确定度优于0．1dB，置信概率为95％。     

新型精密光电高温计

根据温标传递的特点和需要,设计了新的精密光电高温计。该高温计测量黑体的光谱辐射亮度,结合有效波长原地测量技术,直接依据Planck辐射定律计算被测温度,具备单一参考点分度确定温标的技术能力。该高温计测温范围为800℃～2200℃,在小目标和窄谱带的测量条件下,具有分辨率高、辐射源尺寸影响小、自动化测量等特点。在900℃时温度分辨率为0 01℃。在800℃～2200℃温度范围内,置信水平为0 99时,扩展不确定度为1 0℃～2 4℃。结构参数和性能测试表明,精密光电高温计不仅适用于温度精密测量,而且可作为温标的传递标准。     

DC100A直流电流标准的研制

本文介绍的100A直流电流标准源具有0~100A直流标准电流输出能力。该标准利用“零磁通”原理构成的直流电流传感器做反馈元件,结合D/A转换技术,实现了0~100A直流标准电流的输出功能。经过一年多的应用与考核,该标准提供的0~100A电流信号扩展不确定度为1×10-4。     

Direct Current Effects on High-Frequency Properties of Patterned Permalloy Thin Films

We have investigated experimentally direct current (dc) effects on high-frequency properties of two different permalloy (Py) submicrometer patterns of 0.24 $mu$m and 0.55 $mu$m width, 10 $mu$m length, and 100 nm thickness. The natural ferromagnetic resonance (FMR) frequencies for the two samples are about 8.5 and 11.5 GHz. A 50 mA dc produces a FMR frequency reduction of about 1 GHz in both samples. We extracted susceptibility spectra for the samples from the measurement data. We studied inductance variations of Py embedded transmission lines for different dc levels. With 50 mA dc, the operational frequencies of the inductances decreased by 9% and 12.5%. We also tested effects of magnetic fields generated by external magnets on the submicrometer patterns for comparison. To obtain the same magnetization rotation angle, the external magnetic field needs to be about five times larger than the Ampere field created by the direct current. This behavior is unique and may be associated with the increased thermal energy from the Joule heating effects.      

新标准新观念

本文从实验室质量管理体系建立和实施的角度,谈ISO/IEC 17025《检测和校准实验室能力的通用要求》中以顾客为中心,以人为本、预防为主、持续改进.     

一种用于电压标准源的电流扩展电路

介绍了用于对电压标准源进行电流扩展的外接功率放大电路的设计原理 ,该电路通过对称式的设计方法 ,具有附加误差小、跟踪准确度高等优点 ,解决了一般电压源负载能力不足的问题     

Standard Cell Calibration via Current Transfer

The EMF's of standard cells are now being transferred between laboratories over a 1?-km cable with a precision of 4 parts in 108 to provide an instantaneous comparison of the 2e/h and ?p? experiments being carried out at the two facilities. This is accomplished by transferring a constant current that produces a 1-V drop across standard resistors located at both ends of the cable.     

现行SEMI气体标准目录

1．“SEMIC3．18-1102瓶装二氯二氢硅规范，等级97％”和“SEMIC3．31-1102瓶装二氯二氢硅规范，等级99％（暂定）”为“SEMIC56-0305二氯二氢硅（SiH2Cl2）规范和准则”所代替；     

一种新型的交流阻抗计量标准装置

为解决任意阻抗模与阻抗角的交流阻抗的溯源问题,研制了一套新型交流阻抗标准装置,由交流阻抗标准源及交流阻抗标准表组成,在100Hz~1MHz、0.1Ω~1kΩ范围,可对RLC数字电桥、交流阻抗和实物阻抗进行校准,技术指标可以达到0.01%。采用直接测量法、替代测量法和等电位测量法,将交流阻抗标准溯源到实物阻抗标准、电压比例标准和相位标准上,形成了一条完整的交流阻抗溯源链。     

New Thin-Film Multijunction Thermal Converter Design for Improved High-Frequency Performance

New thin-film planar multifunction thermal converters (PMJTC) were developed to improve the high-frequency ac-dc transfer differences. The heater resistor and thermocouples of these PMJTCs were produced on different substrates: an AIN chip for the heaters and polyimide film for the thermocouples, using simple fabrication processes. The thermocouples were moved from the conventional high-potential heater position, and placed close to the ground electrode of the input circuit. This new configuration upgrades the performance of ac-dc transfer differences above 10 kHz by improving both the electromagnetic coupling between the heater and thermocouples and the output resistance of thermocouples. Using a high thermal conductivity AIN substrate, through which heat is conducted from the heater to the hot junctions of the thermocouples, almost the same sensitivity as that of PMJTCs on silicon is obtained.     

Theoretical Principles of a High-Frequency Magnetic Field Standard Based on a Frame Antenna. Part I

An exact solution has been obtained to the integral equation for the current in a frame antenna built with an infinitely narrow gap. The total current at the input is infinite because of the infinite capacity of the gap and the finite thickness of the antenna.     

IEC 61000-3-2新版谐波电流发射测试标准及未来技术发展变化展望

针对IEC 61000-3-2的不同版本的发展演化,分析了最新的IEC谐波电流发射标准4.0版本中若干条款的技术细则,对标准中谐波电流发射限值要求,待测物测量试验配置条款的变化,以及谐波电流测试技术标准化发展趋势进行了详细分析。     

Theoretical Principles for a High-Frequency Magnetic Field Reference Standard Based on a Loop Antenna. Part II

We have derived an integral equation for the current in a loop antenna with a finite gap. We consider the cases of excitation of the loop antenna by an a.c. voltage applied to the gap and by the electromagnetic field of a plane wave. We have obtained the solution of the integral equation for excitation of a loop antenna by an a.c. voltage. We present a formula for the input admittance of a loop antenna that is valid at high frequencies.