Granted Patent
Utility
US 4,644,103 · App. 06/740,972
Tone-responsive circuit for activating an instrumentality interfacing system
Inventor:
Yechiel Rosenfeld
Patented Case
View Patent ↗
Granted: Feb 17, 1987
Filed: Jun 4, 1985
Inventor
Yechiel Rosenfeld
Assignee (at issue)
Base Ten Systems, 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.