FR737991A - - Google Patents
Info
- Publication number
- FR737991A FR737991A FR737991DA FR737991A FR 737991 A FR737991 A FR 737991A FR 737991D A FR737991D A FR 737991DA FR 737991 A FR737991 A FR 737991A
- Authority
- FR
- France
- 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
- H04Q3/00—Selecting arrangements
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Interface Circuits In Exchanges (AREA)
- Monitoring And Testing Of Exchanges (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US543759A US1903837A (en) | 1931-06-08 | 1931-06-08 | Telephone system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| FR737991A true FR737991A (fr) | 1932-12-17 |
Family
ID=24165170
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| FR737991D Expired FR737991A (fr) | 1931-06-08 |
Country Status (3)
| Country | Link |
|---|---|
| US (1) | US1903837A (fr) |
| DE (1) | DE649103C (fr) |
| FR (1) | FR737991A (fr) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2419540A (en) * | 1943-08-28 | 1947-04-29 | Int Standard Electric Corp | Telecommunication switching system |
| US2428024A (en) * | 1945-07-07 | 1947-09-30 | Int Standard Electric Corp | Matched potential electrical control system |
| US2492135A (en) * | 1945-07-07 | 1949-12-27 | Int Standard Electric Corp | Potential matching electrical control system |
| DE945569C (de) * | 1953-08-25 | 1956-07-12 | Telefonbau & Normalzeit Gmbh | Schaltungsanordnung zur vieradrigen Durchschaltung von Vierdrahtleitungen ueber Waehlerstufen |
| US2866004A (en) * | 1954-03-04 | 1958-12-23 | Gen Telephone Lab Inc | Electronic busy test circuit |
| US3193621A (en) * | 1961-11-01 | 1965-07-06 | Gen Dynamics Corp | Telephone line finder |
| US3210477A (en) * | 1962-01-26 | 1965-10-05 | Gen Dynmics Corp | Two-way trunk for interconnecting switchboards |
-
0
- FR FR737991D patent/FR737991A/fr not_active Expired
-
1931
- 1931-06-08 US US543759A patent/US1903837A/en not_active Expired - Lifetime
- 1931-12-29 DE DER83678D patent/DE649103C/de not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| DE649103C (de) | 1937-08-14 |
| US1903837A (en) | 1933-04-18 |