The Inside and the Outside are not the Same -- Experimental Investigations of Ground and Shield Topology

Abstract

This paper presents the results of a series of experimental illustrations of common "shield integrity" and "grounded penetration" design problems which arise whenever various elements of a multi-element system are wired together. The results show that simple topological control techniques can be used to ensure that grounding re­ quirements are satisfied without compromising the shield integrity of a system and that the careful use of properly separated "internal" and "external" ground points can be used to reduce penetrant interference coupling on "grounded" conductors by 40 to 75 dB or more.