An apparatus and method in which a free layer of a spin valve sensor may be stabilized without using permanent magnets are provided. A memory can store a plurality of images and can store account information for a plurality of users. The data from the sensors is processed to extract spatial and temporal parameters as desired. In addition, the diagnosing program searches the first file to determine if any groups of power test pads have a total number of power test pads which is less than a safety value, to indicate if any additional power test pads are required for any particular group. The matrix array of recesses is arranged to strengthen the rigid of the housing under the mating port so as to prevent the deformation of the mating port, which is influenced from the insert force under a condition when the electrical connector mates with a complementary connector.