Granted Patent
Utility
US 4,463,431 · App. 06/383,877
Signal amplitude indicating apparatus
Inventor:
John W. Schumaker
Patented Case
View Patent ↗
Granted: Jul 31, 1984
Filed: Jun 1, 1982
Inventor
John W. Schumaker
Assignee (at issue)
AT&T Technologies Incorporated
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.