FR717671A - Telephone systems - Google Patents
Telephone systemsInfo
- Publication number
- FR717671A FR717671A FR717671DA FR717671A FR 717671 A FR717671 A FR 717671A FR 717671D A FR717671D A FR 717671DA FR 717671 A FR717671 A FR 717671A
- Authority
- FR
- France
- Prior art keywords
- telephone systems
- telephone
- systems
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q1/00—Details of selecting apparatus or arrangements
- H04Q1/18—Electrical details
- H04Q1/30—Signalling arrangements; Manipulation of signalling currents
- H04Q1/32—Signalling arrangements; Manipulation of signalling currents using trains of dc pulses
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Interface Circuits In Exchanges (AREA)
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US717671XA | 1930-06-27 | 1930-06-27 | |
US377973XA | 1930-06-27 | 1930-06-27 | |
US464156A US1898063A (en) | 1930-06-27 | 1930-06-27 | Telephone system |
Publications (1)
Publication Number | Publication Date |
---|---|
FR717671A true FR717671A (en) | 1932-01-12 |
Family
ID=27365285
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
FR717671D Expired FR717671A (en) | 1930-06-27 | 1931-05-27 | Telephone systems |
Country Status (2)
Country | Link |
---|---|
US (1) | US1898063A (en) |
FR (1) | FR717671A (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3432620A (en) * | 1965-12-13 | 1969-03-11 | Scantlin Electronics Inc | Dial long line circuit |
-
1930
- 1930-06-27 US US464156A patent/US1898063A/en not_active Expired - Lifetime
-
1931
- 1931-05-27 FR FR717671D patent/FR717671A/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
US1898063A (en) | 1933-02-21 |
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