Tuned filters with enhanced high frequency response

A tuned filter comprising:

• a single circuit board having first and second opposed major surfaces and first and second opposing sides, the opposed major surfaces being substantially parallel to a single plane and being bisected by a longitudinal axis, the first and second opposing sides being substantially parallel to the longitudinal axis;
• an input terminal connected to the single circuit board, the input terminal having an axis extending substantially parallel to the longitudinal axis;
• an output terminal connected to the single circuit board, the output terminal having an axis extending substantially parallel to the longitudinal axis;
• a filter section associated with the first major surface, the filter section comprising at least two filter circuits with one filter circuit associated with one side of the longitudinal axis and another filter circuit associated with an opposing side of the longitudinal axis, each circuit having a plurality of capacitors, at least one air wound inductor, and at least one wirewound chip inductor, the air wound inductor and the wirewound chip inductor being connected in series with one another;
• at least two ground paths associated with the second major surface, one of the ground paths extending along a portion of the first opposing side and another one of the ground paths extending along a portion of the second opposing side;
• an isolation region separating the at least two ground paths, and extending along the longitudinal axis;
• and
• at least one inductive contact connecting the at least two ground paths, the inductive contact being one of a metallic wire and a metallic trace on the circuit board,
• wherein the inductive contact spans the isolation region and extends along the second major surface.

A tuned filter comprising:

• a single circuit board having first and second opposed major surfaces, the opposed major surfaces being substantially parallel to a single plane and being bisected by a longitudinal axis;
• an input terminal connected to the single circuit board, the input terminal having an axis extending substantially parallel to the longitudinal axis;
• an output terminal connected to the single circuit board, the output terminal having an axis extending substantially parallel to the longitudinal axis;
• a filter section associated with the first major surface, the filter section comprising at least two filter circuits, the filter circuits being separated from one another along the longitudinal axis by at least one first physical shield associated with the first major surface and at least one second physical shield associated with the second major surface, the first and second shields extending substantially perpendicular to the single plane and the longitudinal axis;
• a first circuit run extending along the first major surface, the first circuit run having a first end located adjacent one of the filter circuits and having a second end located adjacent another one of the filter circuits;
• and
• a second circuit run substantially mirroring the first circuit run and extending along second major surface.