Surface mountable transmission line device

Abstract

A transmission line device includes at least two rectangular plates of an insulating material having opposed planar surfaces and edges. A transmission line of a conductive material is on a surface of at least one of the plates and extends between two opposed edges of the plates. The plate having a transmission line thereon has holes therethrough adjacent its opposed edges, which holes extend to the ends of the transmission line. The holes are filled with a conductive material which makes electrical contact to the ends of the holes. Ground planes of a conductive material are on a surface of the plates. The plates are stacked together with the surface having the transmission lines facing a surface of another plate, and the ground planes facing outwardly. The plates are mechanically secured together either by metal clips or by a suitable cement between the opposed surfaces of the plates. Terminals are at the edges of the plates and are connected to the ends of the transmission line and to the ground planes. The terminals may be the clips which secure the plates together, or may be conductive strips along the edges of the plates. The terminals are such that the device can be surface mounted on a printed circuit board with the terminals being seated on and electrically connected to conductors on the printed circuit board.