Granted Patent
Utility
US 5,483,593 · App. 08/146,772
Call progress decoder for multiple cadenced tones on telephone lines
Inventors:
Sanjay Gupta, Timothy Lis
Patented Case
View Patent ↗
Granted: Jan 9, 1996
Filed: Nov 1, 1993
Inventors
Sanjay Gupta
Timothy Lis
Assignee (at issue)
Motorola, Inc.
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.