Abstract: A Guanella type balun with a conductive enclosure (for example, a re-entrant box) between its coupled lines and the magnetic material enclosing its coupled lines. Some embodiments use coupled strip lines. Some embodiments have dielectric material, such as printed circuit board material inside the re-entrant box along with the coupled strip lines. Preferably, the magnetic material is ferrimagnetic. Some preferred magnetic materials are non-conductive.

Abstract: A surface mount balun includes a first stripline segment having a first and second end, a first balanced port connected to the first end, and a second balanced port connected to the second end, a second stripline segment overlapping and coupled to the first stripline segment, and having a third end adjacent to the first end of the first stripline segment and a fourth end disposed approximately adjacent to the center of the first stripline segment, a third stripline segment overlapping and coupled to the first stripline segment, and having a fifth end adjacent to the second end of the first stripline segment and a sixth end disposed approximately adjacent to the center of the first stripline segment, and a third, unbalanced port connected to the sixth end of the third stripline segment.

Abstract: The present invention is directed to a method for making a hybrid material stripline device. The method includes providing an inner layer of material, the inner layer including a dielectric material and at least one conductive sheet. At least one stripline device is formed in the inner layer by processing the at least one conductive sheet. The at least one stripline device is characterized by a surface area footprint. A first exterior layer and a second exterior layer are provided. At least one of the first exterior layer and/or the second exterior layer includes at least one ceramic portion. The at least one ceramic portion has a ceramic surface area greater than or substantially equal to the surface area footprint of the at least one stripline device. At least one of the first exterior layer and/or the second exterior layer further includes a softboard dielectric material. The inner layer of material is sandwiched between the first exterior layer and the second exterior layer.