An electronic apparatus has a housing which is formed with a suction port and an exhaust port. A GNSS receiver 100 includes a receiver 1, a navigation message acquiring unit 3, a navigation message processor 5, and a calculator 6. CPU 21 gives an instruction to an electronic musical instrument 19 to generate a musical tone of a tone color at a timing when a position of the performance apparatus obtained by the geomagnetic sensor and acceleration sensor passes through a sound generation area defined in space, wherein the tone color of the musical tone corresponds to the sound generation area. The switched-on times of the first and second switches are shortened in comparison to switched-on times which are predetermined by the frequency signal, upon detection of a critical operating state. The bag material is a laminate comprising aluminum foil sandwiched between layers of polyester with an inner layer of polyethylene.