| 摘要 |
PROBLEM TO BE SOLVED: To suppress the radiation noise generated by a high-frequency current made to flow by the actions of digital signals on a printed wiring board and radiated from the whole body of a shield box due to cavity resonance. SOLUTION: Electromagnetic waves having a specific frequency and radiated from the printed wiring board covered with the shield box are suppressed by disposing a metallic antenna member in the shield box, in a state where the antenna member is not connected electrically to the printed wiring board. When the length of the antenna member is adjusted, a frequency to be suppressed can be suppressed surely. COPYRIGHT: (C)2004,JPO&NCIPI
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