IP Library › Granted Patent US 4,611,325
Granted Patent Utility
US 4,611,325 · App. 06/685,198

DTMF receiver sense and control arrangement

Inventors: Leo V. Jones, Jr., A. Lee Walsh
Patented Case View Patent ↗
Granted: Sep 9, 1986 Filed: Dec 21, 1984
Inventors
Leo V. Jones, Jr.
A. Lee Walsh
Assignee (at issue)
GTE Communication Systems Corporation

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Quick Facts
Patent No.
US 4,611,325
App. No.
06/685,198
Filed
1984-12-21
Granted
1986-09-09
Kind
A