Granted Patent
Utility
US 4,242,631 · App. 05/911,367
Front-end circuit apparatus for impedance measurements and the like
Inventor:
Henry P. Hall
Patented Case
View Patent ↗
Granted: Dec 30, 1980
Filed: Jun 1, 1978
Inventor
Henry P. Hall
Assignee (at issue)
Genrad, Inc.
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.