| 摘要 |
PURPOSE:To improve a characteristic by enclosing a surface acoustic wave convolver in a metallic package and connecting a receiving case to the ground pattern of a printing wiring board in a prescribed position or providing an ground terminal in the prescribed position CONSTITUTION:A metallic package to enclose in an SAW convolver is connected to ground patterns 32 and 34 of a wiring board at plural points 37, output matching circuits 27 and 28 are arranged in the both sides of the package 26 and terminals 29 and 30 are connected. Further, the package 26 is connected to the ground pattern 32 of the wiring board 31 or to a case 33 directly in a nearest position 38 to the receiving case 33. Thus, the package 26 shields the electric coupling of the input output part of the SAW convolver, an ground current to conduct to the ground pattern around the input output terminal of the package 26 is conducted through the metallic package 33, the electric potential of the ground pattern is brought nearer to an ground electric potential and the level of an unnecessary wave due to the coupling between an input and an output can be reduced.
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