Abstract: A clip for surface-mounting a coupled-dual resonator crystal to a circuit board includes an elongated housing shaped complementary to the housing of the crystal and having an opening along a side for receiving the crystal. A tab spaces first and second shielding portions which overlie the end of the crystal housing. A first shield portion engages the middle ground terminal of the crystal shielding the input and output terminals, while the second shield extends from the first shield to overlie the output terminal, likewise shielding it from the input terminal. Distal portions of the input, output and common terminals, together with pads at the opposite end of the clip, mount the clip mechanically to the surface of a circuit board.

Abstract: A multi-resonator crystal body is physically supported by electrical lead wires extending from a support substrate having individual shaped electrical conductors thereon which are thus connected to each resonator on the crystal body such that the individual resonator electrodes can be selectively short-circuited, or open-circuited, or displayed to an external electrical network to facilitate final finishing of the resonator electrodes. Predetermined electrical circuits (e.g. a short-circuit effected by conductive cement or paint) are thereafter connected across some of the resonator electrodes via the shaped conductive areas on the support substrate before the entire assembly is encapsulated in a standard pin connector housing arrangement. Besides greatly facilitating the tuning of individual crystal resonators to desired frequencies during the finishing operation, this mounting arrangement is also believed to provide improved temperature characteristics and/or shock mounting of the crystal body.

Abstract: A crystal filter structure and fabrication method therefor. The crystal filter is constructed as a thick film circuit on a ceramic substrate. The coupling capacitors are painted on the ceramic substrate as part of the thick film circuit. The capacitors are laser trimmed to precise tolerance in order to provide a crystal filter having precise characteristics.