A thin metallic ferromagnetic alloy ribbon is annealed by continuously transporting it through an oven in order to induce specific magnetic characteristics and in order to remove a production-inherent longitudinal curvature of the ribbon. A plurality of primary inductors are coupled between differential output nodes of the respective low noise amplifiers. A light beam from the first intermediate image passes through a polarizing beam splitter and is reflected by a concave reflecting mirror to form a second intermediate image in the polarizing beam splitter. The touch panel is located on the front side of the switch liquid crystal panel. A temperature control system is operably coupled to the air heating device and the air cooling device, the control system being configured to maintain a predetermined air temperature within the compartment in response to a sensed compartment temperature. It comprises elastic elements acting on the card when the latter is in reading position in three substantially perpendicular active directions.