Granted Patent
Utility
US 4,470,070 · App. 06/412,898
Frequency translation phase-locked loop television sound detection system
Inventor:
Patrick D. Griffis
Patented Case
View Patent ↗
Granted: Sep 4, 1984
Filed: Aug 30, 1982
Inventor
Patrick D. Griffis
Assignee (at issue)
RCA 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.