Magnetic field strength H is often measured with so-called H-coils. These are typically wound with a wire on flat thin paramagnetic formers, which allows them to be placed as close as possible to the surface of the magnetic sample under test. However, such wire-wound H-coils are not completely immune to off-axis H components. This paper presents a novel concept of an H-coil design which significantly improves the immunity to off-axis components. Such H-coils can be made by utilising the precision of printed-circuit boards (PCB) and experimental results are shown for a prototype. PCB technology opens the possibility of making precisely aligned large H-coils, easy extrapolation of values towards the surface of the sample and accommodating wires for B-coils.
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