GB795699A - Improvements in or relating to telephone systems - Google Patents
Improvements in or relating to telephone systemsInfo
- Publication number
- GB795699A GB795699A GB3409655A GB3409655A GB795699A GB 795699 A GB795699 A GB 795699A GB 3409655 A GB3409655 A GB 3409655A GB 3409655 A GB3409655 A GB 3409655A GB 795699 A GB795699 A GB 795699A
- Authority
- GB
- United Kingdom
- Prior art keywords
- circuit
- arrangement
- wire
- transformers
- transformer
- 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
- H04M—TELEPHONIC COMMUNICATION
- H04M3/00—Automatic or semi-automatic exchanges
- H04M3/40—Applications of speech amplifiers
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Interface Circuits In Exchanges (AREA)
Abstract
795,699. Automatic exchange systems. AUTOMATIC TELEPHONE & ELECTRIC CO., Ltd. Nov. 7, 1956 [Nov. 29, 1955], No. 34096/55. Class 40 (4). A pair of transformers in conjunction with a two-position switching device is arranged, in one position of the device to use the transformers individually to couple the two four-wire circuits together, and in the other position to operate as a hybrid transformer for coupling a fourwire circuit to a two-wire circuit. In the arrangement shown, with relay HCA unoperated, circuit AB from the switching equipment SE is coupled to circuit AB to the transmission equipment (e.g. carrier equipment) CE by windings 1, 2 and 5, 6 of transformer 1TRA, whilst coils 1, 2 and 3, 4 of transformer 2TRA couple the CD circuits. With HCA operated the two transformers are connected as a hybrid circuit for connecting a two-wire circuit AB(SE) to a four-wire circuit AB, CD(CE) the CD circuit on the SE side being connected by the switching equipment to a balance network. The arrangement is thus suitable for a " tail-eating " connection with another similar circuit as may be required for a connection completed through an operator's position (the respective CD circuits being interconnected with a cross-over). In either case the CD wires from SE are connected to relays RC, RD which may be used for controlling V.F. signalling. An arrangement with a slightly different arrangement of relay contacts and a built-in balance for the hybrid is also described, Fig. 1 (not shown).
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB3409655A GB795699A (en) | 1955-11-29 | 1955-11-29 | Improvements in or relating to telephone systems |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB3409655A GB795699A (en) | 1955-11-29 | 1955-11-29 | Improvements in or relating to telephone systems |
Publications (1)
Publication Number | Publication Date |
---|---|
GB795699A true GB795699A (en) | 1958-05-28 |
Family
ID=10361330
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB3409655A Expired GB795699A (en) | 1955-11-29 | 1955-11-29 | Improvements in or relating to telephone systems |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB795699A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3156775A (en) * | 1959-12-02 | 1964-11-10 | Itt | Telephone converter |
-
1955
- 1955-11-29 GB GB3409655A patent/GB795699A/en not_active Expired
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3156775A (en) * | 1959-12-02 | 1964-11-10 | Itt | Telephone converter |
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