The authors have between them more than 60 years of experience in making electrical measurements in National Measurement Laboratories. These laboratories are the source of measurement standards and techniques for science and engineering and are dedicated to maintaining the international system of units (SI) by establishing and disseminating the values of measurement standards with the lowest possible uncertainty. Careful attention to detail is required in designing measurement systems that eliminate electrical interference and are as simple and as close to first principles as possible. This book draws on their experience by offering guidance and best practice for designing sensitive electrical measurement circuits.

Lord Kelvin (William Thomson), arguably Britain's most eminent scientist after Newton, spent much of his life in work which led to the development of today's electrical units and standards. Despite his influence, there are few biographies of stature (largely due to the abstruse nature of much of his technical research). This treatment concentrates upon his work in three phases; discovery of the fundamental concepts and coding them into universal laws, leading the adoption of the metric system, and securing worldwide use of units and standards (now the IEC system).

The need to measure electrical power is common to many branches of science and engineering. This book presents a wide-ranging survey of the many types of radio-frequency and microwave power meter and the techniques which are used for calibrating and intercomparing them. The frequency range is 1 MHz to 200 GHz.