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:
Jul. 09, 1991
Filed:
Jul. 05, 1989
Applicant:
Inventor:
Robert G Kinsman, Naperville, IL (US);
Assignee:
Motorola, Inc., Schaumburg, IL (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03H / ;
U.S. Cl.
CPC ...
333188 ; 333189 ;
Abstract
An improved crystal notch filter is disclosed with a large passband-to-stopband ratio. The filter has individual sections with discrete crystal devices. In one embodiment as a 55 MHz trap, the filter has a passband from about 50 MHz to about 212 MHz with a 1 KHz stop band about a center frequency that may be tuned by means of a laser-trimmed bridging resistor.