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EM电子成立于1979年，其最初期项目之一便是对低功率直流放大器进行研究。EM电子开展了计算和实验室试验以考察在nV情况下开展探测的可能性，这是一项令人倍感鼓舞的项目。随后，这一工作有条不紊的展开。在经过一段研发期之后，推出了一个毫微电压计样品。
此后，在位于特定顿的国家物理实验室电子科学部对该样品进行了论证。很快，毫微电压计便获得第一份订单。
该型新仪器被命名为N1。若干技术期刊刊登文章对其进行宣传推广，包括《物理通报》也刊登了相关文章，展示了相关结果。EM低功率探测仪器的订单从世界各国纷至沓来，出现在许多国家的计量检测机构和研究机构内。
随后，为了更为精确的测定电流基本元件，国家物理实验室提出了功率更低的电压测量需求。
随后，为了满足放大器在高线性条件下对极低功率直流电压进行测量时需将交流电转换为直流电的需求，对于该仪器提出了新的要求。这一研发最终变成了A14的升级版：A7。这一技术被用于新N31的进一步应用和发展之中。
EM测量技术的研究领域之一被应用于精确阻抗测定的赫尔效应之中。
1990年，EM电子因其在研发极低功率直流测量仪器方面取得的卓越技术成就而获得了女王奖。
之前，在将EM nV电压计、微伏电压计和nV放大器以通过RS232串行链路或IEEE并行总线控制计算机等方面，人们提出了大量请求。这就提出了一个问题，那就是：极低功率电压测量，以及由计算机在IEEE并行总线上传输时所产生的极高电子噪声。
EM电子获得贸易与工业部的“SMART“奖，以促进将极低功率测量问题的隔离，并在密集研发项目之后，获得通过计算机对极低功率测量仪器进行控制的能力。这一隔离能力能被适用于N31中。
自从第一台N1问世以来，其他的研发项目在这些年内也取得了一些进展，大量仪器被相继推出，其中可对低至数微伏进行衡量，而线性则约为百万分之一，能够有效的衡量在氮温度下对电源进行测量的能力，以及在完全隔离的情况下开展测量的活动。
未来的研发领域是低功率直流放大模块。可以被安装在打印电路板上的小型放大器能够适用于小空间，或者很经济的被用于多渠道系统之中，也能对低至nV级别的电压进行测量，目前是EM产品中的重要组成部分。开展热耦合温度测量的过程中，这些模块十分理想，检测功率等级确保测量灵敏度要高于之前数倍。这些模块相对较低的成本表明，在多渠道系统中，每一条渠道都存在方法效应，因此这一计划在经济上是可行的。对于渠道的扫描可以在电压稍高的情况下完成。
EM电子为国家物理实验室计量、标准和科学研究单位提供极低功率的测量仪器。
EM电子目前专注于新的极低直流放大器的研发。A10、A20和A22的研发工作毫不停息，以便最大限度的使用新技术。A20的设计目的是用于极低功率的工作，包括对低温来源的测量。
研发是一种持续性的工作，尚在规划中的新产品令人感到激动。
About EM Electronics
EM Electronics was formed in 1979. One of the earliest projects undertaken was the study of very low level DC amplification. Calculations and laboratory experiments were carried out to investigate the feasibility of detection in the nanovolt region, which appeared to be quite encouraging. The work progressed and after a period of development a prototype nanovoltmeter was produced.
The original prototype instrument was demonstrated to the Division of Electrical Science at the National Physical Laboratory in Teddington, and shortly after this a first instrument was ordered.
Word of the new instrument, designated the N1, spread and a number of technical journals, including 'Physics Bulletin' published articles, with the result that interest was shown, orders were received from various countries and EM low level detection equipment appeared in calibration institutions and research establishments in many countries.
Subsequently the National Physical Laboratory had a requirement for even lower levels of voltage measurement in their quest for more accurate determination of the basic unit of electric current. A study was undertaken and, following development, the first EM DC Picovoltmeter was produced.
Later, there was a further requirement in the conversion of AC to DC measurements for an amplifier which would detect ultra low levels of DC voltage with very high linearity. This development became the A7 which was upgraded to the A14 and the technology is applied and developed further in the new N31.
An area of research to which EM measurement techniques have been applied is the quantized Hall effect for very accurate resistance determination.
In 1990 EM Electronics won the Queen's Award for Technological Achievement for the development of highly successful ultra low level DC measuring instruments.
Frequent requests were made to connect EM Nanovoltmeters, Picovoltmeters, and Nanovolt Amplifiers to controlling computers via RS232 serial link or an IEEE parallel bus. This presented a problem because of the very low measurement level and the high degree of electrical noise generated by computers and transmitted on an IEEE bus.
EM Electronics won a Department of Trade and Industry 'SMART' award to enable research into the problems of isolating low level measurements, and after a program of intensive research and development, produced the capability to control ultra low level measuring instruments by computers. This isolation capability has been applied in the N31.
Other research and development projects have been undertaken over the years since the first N1 was produced with the result that EM Electronics produced a range of instruments which includes detection down to a few picovolts, linearity to better than one part per million, a nanovoltmeter which, while remaining at room temperature, can efficiently measure a source at helium temperature and now the ability to make measurements with complete isolation.
A further field of development is low level DC amplifying modules. Small amplifiers, which can be mounted on a printed circuit board, fit into small spaces or be used economically in multi channel systems and which can measure down to nanovolt levels, are now an important part of the EM range. These modules are ideal for making thermocouple temperature measurements, and the detection level ensures that the measurement sensitivity is many times greater than was previously possible.
The comparatively low cost of these modules means that multi-channel systems, with amplification in each channel, are economically viable, and the scanning of the channels can now be accomplished at a higher level.
EM Electronics supply ultra low level measuring equipment to National Physical Laboratories, calibration, standards and scientific research Institutions, industry and medical centres in all parts of the world.
EM Electronics is now specialising on the development of a new range of ultra low level DC amplifiers. The A10, A20 and A22 are being developed continuously to make use of new techniques and components as they become available. The A20 in particular is designed for extremely low level work, including the measurement of cryogenic sources.
Development is continuing and an exciting range of new products is planned.
The website will be updated with the latest information as the new amplifiers become available.
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