PORTABLE RADIO EQUIPMENT

PURPOSE: To make an antenna small by laminating a sheet insulation member with a conductor coated thereto to spirally form the conductor in succession thereby using the winding for an inductor element without deviation of the resonance frequency due to a surrounding material. CONSTITUTION: A resin case 1 covers a metallic case 2 and the metallic case 2 incorporates a radio circuit section 3 to apply electromagnetic shielding to the radio circuit section 3. A connection terminal 5 to feed an antenna is connected to an output terminal of the radio circuit section 3, the connection terminal 5 is led to the outside of the metallic case 2 in a state that no electromagnetic shielding is interfered and connects electrically to an inductor element 7 whose electric length is nearly λ/4. The inductor element 7 is formed by forming a ferrite material into a green sheet with low dielectric constant and low loss, making a via-hole to the sheet, printing a conductor whose resistance is low to the sheet and laminating and integrating the sheet to allow the conductor to be a continuous winding and baking the sheet. The small sized inductor element is mass-produced and the performance is kept stable.