Granted Patent
Utility
US 4,267,537 · App. 06/034,697
Right circular cylindrical sector cavity filter
Inventor:
Paul R. Karmel
Patented Case
View Patent ↗
Granted: May 12, 1981
Filed: Apr 30, 1979
Inventor
Paul R. Karmel
Assignee (at issue)
Communications Satellite Corporation
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.