Granted Patent
Utility
US 4,259,649 · App. 06/061,100
Electroacoustic delay line apparatus
Inventor:
John Christopher De Klerk
Patented Case
View Patent ↗
Granted: Mar 31, 1981
Filed: Jul 26, 1979
Inventor
John Christopher De Klerk
Assignee (at issue)
Westinghouse Electric Company LLC
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.