The vibrating head magnetometer--Instrument for the measurement of magnetic transitions in high coercive force films

The magnetization pattern recorded in high coercive force media, such as magnetic tapes or discs, is measured with the vibrating head magnetometer (VHM) by vibrating a recording head parallel to the surface of the medium and along the track length. The VHM can be used with small, irregular-shaped samples. It can be used to measure precisely the shape of recorded magnetic transitions. Application of the VHM to the precise location of dropouts on prerecorded samples and to the alignment of a recording head with respect to a prerecorded track is described. Measurements have been made with the VHM of the half peak width and relative peak signal of isolated transitions in Co alloy films. The half peak width was found to be proportional to .