GB548473A - Improvements in 4-wire terminating arrangements in electrical communication systems - Google Patents
Improvements in 4-wire terminating arrangements in electrical communication systemsInfo
- Publication number
- GB548473A GB548473A GB952041A GB952041A GB548473A GB 548473 A GB548473 A GB 548473A GB 952041 A GB952041 A GB 952041A GB 952041 A GB952041 A GB 952041A GB 548473 A GB548473 A GB 548473A
- Authority
- GB
- United Kingdom
- Prior art keywords
- range
- mod
- way
- modulators
- wire
- 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
- H04B—TRANSMISSION
- H04B3/00—Line transmission systems
- H04B3/02—Details
- H04B3/36—Repeater circuits
- H04B3/38—Repeater circuits for signals in two different frequency ranges transmitted in opposite directions over the same transmission path
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
Abstract
548,473. Repeating and multiplex translating systems. STANDARD TELEPHONES & CABLES, Ltd. (International Standard Electric Corporation). July 26, 1941, No. 9520. [Class 40 (iv)] Hybrid coils are avoided at the junction between a two-way two-wire path and two one-way paths by the provision of a reversiblemodulator in the two-way path and filters appropriate to the respective side-bands in the one-way paths. The principle is applied to the termination of a four-wire repeating system, Fig. 1 (not shown), to the two sides of a two-wire repeater, Fig. 3 (not shown), to a system with one voice frequency and one carrier channel, Fig. 4 (not shown), for coupling the low frequency and high-frequency lines to the frequency changing arrangements, and to multiplex carrier systems, Figs. 5 and 2. In the arrangement shown in Fig. 5, speech currents from a number of telephone lines are spread in a first modulator stage over a range from 60 to 108 KC. and this range is passed through a reversible modulator MOD-G, the lower side-band being used for the outgoing line. The incoming currents cover the same range but are brought by a modulator MOD-R to the range corresponding to the upper sideband and then by MOD-G to the range 60- 108KC. In the arrangement shown in Fig. 2, identical reversible first modulators, individual reversible second modulators such as MOD 1-2 and individual receiving modulators such as MODR-1 are provided.
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
BE439378D BE439378A (en) | 1941-07-26 | 1940-09-26 | |
GB952041A GB548473A (en) | 1941-07-26 | 1941-07-26 | Improvements in 4-wire terminating arrangements in electrical communication systems |
FR887180D FR887180A (en) | 1941-07-26 | 1941-12-11 | Electrical communications systems |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB952041A GB548473A (en) | 1941-07-26 | 1941-07-26 | Improvements in 4-wire terminating arrangements in electrical communication systems |
Publications (1)
Publication Number | Publication Date |
---|---|
GB548473A true GB548473A (en) | 1942-10-12 |
Family
ID=9873551
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB952041A Expired GB548473A (en) | 1941-07-26 | 1941-07-26 | Improvements in 4-wire terminating arrangements in electrical communication systems |
Country Status (3)
Country | Link |
---|---|
BE (1) | BE439378A (en) |
FR (1) | FR887180A (en) |
GB (1) | GB548473A (en) |
-
1940
- 1940-09-26 BE BE439378D patent/BE439378A/xx unknown
-
1941
- 1941-07-26 GB GB952041A patent/GB548473A/en not_active Expired
- 1941-12-11 FR FR887180D patent/FR887180A/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
FR887180A (en) | 1943-11-05 |
BE439378A (en) | 1940-10-31 |
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