Granted Patent
Utility
US 5,336,989 · App. 07/762,917
AC mains test apparatus and method
Inventor:
Bruce E. Hofer
Patented Case
View Patent ↗
Granted: Aug 9, 1994
Filed: Sep 19, 1991
Inventor
Bruce E. Hofer
Assignee (at issue)
Audio Presicion
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.