BS EN 61189-2-721. Measurement of Relative Permittivity & Loss Tangent for Copper Clad Laminate at Microwave Frequency Using Split Post Dielectric Resonator Printed circuits, Printed-circuit boards, Electronic equipment & components, Electrical insulating materials, Testing conditions, Chemical analysis & testing, Accuracy, Precision, Chemical-resistance tests, Sodium hydroxide, Test specimens, Impregnated materials, Gelation, Time, Plastics, Determination of content, Compressible flow, Flow measurement, Electrical testing, Electrical resistivity, Resistance measurement, Electric arcs, Test equipment, Volatile matter determination, Thermal testing, Thermal-shock tests, Blistering, Pull-out tests, Peeling tests, High-temperature testing, Cleaning, Position, Electrodes