Granted Patent
Utility
US 5,442,695 · App. 08/364,415
Ringer circuit
Inventors:
Artur Bardl, Emil Navratil
Patented Case
View Patent ↗
Granted: Aug 15, 1995
Filed: Dec 27, 1994
Inventors
Artur Bardl
Emil Navratil
Assignee (at issue)
Siemens Aktiengesellschaft
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.