| 摘要 |
<p>The device comprises a planar substrate of dielectric material, a tuned circuit being provided on the substrate in circuit configuration and resonant at a particular frequency. The tuned circuit has a pair of conductive areas on respective opposite surfaces of the substrate to define a capacitor of the tuned circuit. An arrangement within the conductive areas defines a path between the conductive areas and through the substrate at which an arc discharge will preferentially occur in response to an electromagnetic field at that frequency of sufficient energy, and operative to destroy the resonant properties of the tuned circuit. - The latter arrangement includes an indented portion n near at least one of the conductive areas providing a spacing between the conductive areas at the indented portion. The spacing is less than the spacing between the conductive areas outside of the indented portion. (12pp Dwg.No.1/16)</p> |
