Granted Patent
Utility
US 4,270,218 · App. 06/119,348
Continuous tune all-channel selector
Inventor:
Richard Smirl
Patented Case
View Patent ↗
Granted: May 26, 1981
Filed: Feb 7, 1980
Inventor
Richard Smirl
Assignee (at issue)
Zenith Radio 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.