Abstract: A tuned filter having enhanced high frequency response includes a circuit board having first and second opposed major surfaces and first and second opposing sides. The opposed major surfaces are substantially parallel to a single plane and are bisected by a longitudinal axis. The first and second opposing sides are substantially parallel to the longitudinal axis. An input terminal and an output terminal are connected to the single circuit board. A filter section is associated with the first major surface. At least two ground paths are associated with the second major surface. One of the ground paths extends along a portion of the first side, and another one of the ground paths extends along a portion of the second opposing side. An isolation region separates the at least two ground paths, and extends along the longitudinal axis.