Abstract: Provided is a air purge device that can effectively discharge air.

Abstract: In order to eliminate the unnecessary power consumption caused by the increase in frequency associated with wireless communication systems using electromagnetic induction techniques, the wireless communication system of the present invention modulates and transmits a magnetic field in accordance with information. A close-range receiver is provided with an amorphous magnetic impedance element having an impedance which varies in accordance with the modulated characteristic of the magnetic field. Use of an amorphous magnetic impedance element in the receiver results in a reduction in power and increase in sensitivity of the device.

Abstract: A miniature radio apparatus for use in transmission or reception of electic waves has a pair of antenna terminals insulated from each other. The pair of antenna terminals are so formed as to be brought into contact with, or to be capacitively-coupled to, different parts of the human body, respectively. One of the pair of antenna terminals is formed so as to be brought into contact with one of the arms, ears, or fingers of the user. The miniature radio apparatus also has a detection/control device for detecting whether the antenna terminals are in contact with, or capacitively-coupled to, different parts of the human body, respectively, and controlling the transmission or reception of electric waves. Consequently, it is possible to obtain a practical gain, and also to enlarge the range of communication so that the quality of communication is improved. It is, furthermore, possible to receive electric waves without an arm band antenna.