Granted Patent
Utility
US 5,227,748 · App. 07/744,945
Filter with electrically adjustable attenuation characteristic
Inventor:
Peter Sroka
Patented Case
View Patent ↗
Granted: Jul 13, 1993
Filed: Aug 14, 1991
Inventor
Peter Sroka
Assignee (at issue)
Technophone Limited
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.