SE7402969L - - Google Patents
Info
- Publication number
- SE7402969L SE7402969L SE7402969A SE7402969A SE7402969L SE 7402969 L SE7402969 L SE 7402969L SE 7402969 A SE7402969 A SE 7402969A SE 7402969 A SE7402969 A SE 7402969A SE 7402969 L SE7402969 L SE 7402969L
- Authority
- SE
- Sweden
- Prior art keywords
- output
- earthing
- key
- exchange
- currents
- Prior art date
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M3/00—Automatic or semi-automatic exchanges
- H04M3/42—Systems providing special services or facilities to subscribers
- H04M3/58—Arrangements for transferring received calls from one subscriber to another; Arrangements affording interim conversations between either the calling or the called party and a third party
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE7402969A SE7402969L (de) | 1974-03-06 | 1974-03-06 | |
GB811175A GB1494136A (en) | 1974-03-06 | 1975-02-26 | Telephone exchanges |
DE19752508547 DE2508547A1 (de) | 1974-03-06 | 1975-02-27 | Erfassungsschaltung fuer telefonnebenstellen |
IT2093075A IT1033426B (it) | 1974-03-06 | 1975-03-05 | Rivelatore di chiamate di richiesta in centrali telefoniche |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE7402969A SE7402969L (de) | 1974-03-06 | 1974-03-06 |
Publications (1)
Publication Number | Publication Date |
---|---|
SE7402969L true SE7402969L (de) | 1975-09-08 |
Family
ID=20320429
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
SE7402969A SE7402969L (de) | 1974-03-06 | 1974-03-06 |
Country Status (4)
Country | Link |
---|---|
DE (1) | DE2508547A1 (de) |
GB (1) | GB1494136A (de) |
IT (1) | IT1033426B (de) |
SE (1) | SE7402969L (de) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NL7904429A (nl) * | 1979-06-06 | 1980-12-09 | Philips Nv | Stroomdetectie-inrichting voor een automatische telefooncentrale. |
DE3108264C2 (de) * | 1981-03-05 | 1984-05-30 | Deutsche Fernsprecher Gesellschaft Mbh Marburg, 3550 Marburg | Schaltungsanordnung zur Erkennung des Schaltzustandes einer Erdtaste eines Fernsprechapparates |
-
1974
- 1974-03-06 SE SE7402969A patent/SE7402969L/ not_active Application Discontinuation
-
1975
- 1975-02-26 GB GB811175A patent/GB1494136A/en not_active Expired
- 1975-02-27 DE DE19752508547 patent/DE2508547A1/de active Pending
- 1975-03-05 IT IT2093075A patent/IT1033426B/it active
Also Published As
Publication number | Publication date |
---|---|
GB1494136A (en) | 1977-12-07 |
DE2508547A1 (de) | 1975-09-11 |
IT1033426B (it) | 1979-07-10 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
NAV | Patent application has lapsed |
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