Invention Grant
- Patent Title: Telephone-exchange system
-
Application No.: US18013217Application Date: 1917-07-12
-
Publication No.: US1350536APublication Date: 1920-08-24
- Inventor: WRIGHT JOSEPH L
- Applicant: JAMES R GARFIELD
- Assignee: James R Garfield
- Current Assignee: James R Garfield
- Priority: US18013217 1917-07-12; US1912680015 1912-02-26; US18013117 1917-07-12
- Main IPC: H04M1/65
- IPC: H04M1/65 ; H04Q3/00
Public/Granted literature
- US20230253000A1 SIGNAL PROCESSING DEVICE, SIGNAL PROCESSING METHOD, AND PROGRAM Public/Granted day:2023-08-10
Information query
