Granted Patent
Utility
US 4,291,354 · App. 06/045,558
Extended life multichannel magnetic transducer
Inventor:
James Chase
Patented Case
View Patent ↗
Granted: Sep 22, 1981
Filed: Jun 4, 1979
Inventor
James Chase
Assignee (at issue)
Ampex 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.