The book describes measurements and application of sensitive electrical circuits, with examples of the ultimate in noisematching and interference elimination, in precise and accurate voltage, current and power measurements demonstrating the elegance, flexibility and utility of coaxial AC bridges. It also serves to update an earlier publication by one of the authors and includes more recent work on AC measurements of quantum Hall resistance to provide a primary quantum standard of impedance and the extension of coaxial networks to higher frequencies. Contents List of figures xiii Abstract xxiii Preface xxv Acknowledgements xxvii 1 Introduction 2 Sources, detectors, cables and connectors 3 The concept of a low-frequency coaxial network 4 Impedance measurement 5 General principles of accurate impedance measurement 6 Impedance standards 7 Transformers 8 General considerations about impedance comparison networks 9 Bridges to measure impedance ratios 10 Application of interference-free circuitry to other measurements References Appendix 1 Appendix 2 Appendix 3 Appendix 4 Index Contents xi