IP Library › Granted Patent US 4,239,941
Granted Patent Utility
US 4,239,941 · App. 06/016,672

Ringing signal generator

Inventors: John A. Gauthier, David M. Shaver, John R. Ramsay
Patented Case View Patent ↗
Granted: Dec 16, 1980 Filed: Mar 1, 1979
Inventors
John A. Gauthier
David M. Shaver
John R. Ramsay
Assignee (at issue)
GTE Automatic Electric Laboratories, Incorporated

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Quick Facts
Patent No.
US 4,239,941
App. No.
06/016,672
Filed
1979-03-01
Granted
1980-12-16
Kind
A