Granted Patent
Utility
US 4,658,161 · App. 06/765,731
Split phase loop
Inventor:
John R. Spencer
Patented Case
View Patent ↗
Granted: Apr 14, 1987
Filed: Aug 13, 1985
Inventor
John R. Spencer
Assignee (at issue)
Hewlett-Packard Company, L.P.
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.