Invention Grant
- Patent Title: Telephone system
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Application No.: US23370638Application Date: 1938-10-07
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Publication No.: US2204759APublication Date: 1940-06-18
- Inventor: HUBBARD FRANCIS A
- Applicant: BELL TELEPHONE LABOR INC
- Assignee: Nokia Bell Labs
- Current Assignee: Nokia Bell Labs
- Priority: US23370638 1938-10-07
- Main IPC: H04M1/272
- IPC: H04M1/272 ; H04M1/50 ; H04Q3/42
Information query
