The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 06, 1989
Filed:
Jan. 29, 1988
Mark I Van Horn, Bedford, TX (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
Coupled transmission line resonators, such as those in a solid-dielectric ceramic block filter, are fabricated with tuning regions formed by notches in the outer conductor extending longitudinally parallel with the inner conductors from both the low-impedance ends and the high-impedance ends of the resonators. Removing conductive material from the notches in the vicinity of the low-impedance ends of the resonators decreases their resonant frequencies; removing conductive material from the notches in the vicinity of their high-impedance ends increases their resonant frequencies. Sensitivity of tuning depends on the depth of the notches. By situating all tuning regions along a common side of a filter, tuning both higher and lower in frequency may be accomplished without a need to re-orient the filter in a production-line fixture.