Granted Patent
Utility
US 4,922,368 · App. 07/275,723
Method and apparatus for detecting and discriminating faults in transmission circuits
Inventor:
Allan T. Johns
Patented Case
View Patent ↗
Granted: May 1, 1990
Filed: Nov 23, 1988
Inventor
Allan T. Johns
Assignee (at issue)
NATIONAL RESEARCH DEVELOPMENT 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.