Granted Patent
Utility
US 4,289,939 · App. 06/108,179
Longitudinal balance arrangements for two-to-four wire telecommunication line circuits
Inventor:
John S. Arnold
Patented Case
View Patent ↗
Granted: Sep 15, 1981
Filed: Dec 28, 1979
Inventor
John S. Arnold
Assignee (at issue)
The Plessey Company 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.