GB525462A - Improvements in or relating to two-way telephone and telegraph circuits - Google Patents
Improvements in or relating to two-way telephone and telegraph circuitsInfo
- Publication number
- GB525462A GB525462A GB5816/39A GB581639A GB525462A GB 525462 A GB525462 A GB 525462A GB 5816/39 A GB5816/39 A GB 5816/39A GB 581639 A GB581639 A GB 581639A GB 525462 A GB525462 A GB 525462A
- Authority
- GB
- United Kingdom
- Prior art keywords
- way
- network
- arrangement
- circuit
- feb
- 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
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/38—Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
- H04B1/40—Circuits
- H04B1/54—Circuits using the same frequency for two directions of communication
- H04B1/58—Hybrid arrangements, i.e. arrangements for transition from single-path two-direction transmission to single-direction transmission on each of two paths or vice versa
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
- Measurement Of Resistance Or Impedance (AREA)
Abstract
525,462. Two-way transmission. TELEFUNKEN GES. FUR DRAHTLOSE TELEGRAPHIE. Feb. 21, 1939, No. 5816. Convention date, Feb. 22, 1938. [Class 40 (iv)] In a circuit involving a balancing network at the junction between a two-way and two one way lines, means are provided for measur ing the want of balance and for adjusting the network automatically or otherwise while the circuit is in use. The test currents which are applied to the receiving branch are picked up in the sending branch and measured or used to control the impedance of a valve acting as an element of the network or to control a regulating resistance by means of a motor or step-by-step switch. In the arrangement using a valve impedance the test current is applied continuously and is outside the range of the communication frequencies. The Figure shows an arrangement in which test currents from Up are prevented by the use of tapped transformers T1, T2, T3, T4 from reaching the two-way line. The degree of unbalance is represented by the difference between the test current voltages developed across resistances R1, R2. These may be filtered out, rectified separately and applied jointly to an indicating or controlling circuit. The regulators or rectifiers are preferably slow-acting. A known arrangement is referred to in which the balancing network is automatically adjusted on the occurrence of a disturbance of long duration.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE525462X | 1938-02-22 |
Publications (1)
Publication Number | Publication Date |
---|---|
GB525462A true GB525462A (en) | 1940-08-28 |
Family
ID=6552620
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB5816/39A Expired GB525462A (en) | 1938-02-22 | 1939-02-21 | Improvements in or relating to two-way telephone and telegraph circuits |
Country Status (2)
Country | Link |
---|---|
FR (1) | FR850637A (en) |
GB (1) | GB525462A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3059060A (en) * | 1956-12-14 | 1962-10-16 | Int Standard Electric Corp | Electric signalling circuits |
GB2139055A (en) * | 1983-04-28 | 1984-10-31 | Darome Inc | Automatic nulling teleconferencing circuit |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3781684A (en) * | 1970-03-24 | 1973-12-25 | Us Army | Single-antenna repeater system utilizing hybrid transformers |
-
1939
- 1939-02-21 GB GB5816/39A patent/GB525462A/en not_active Expired
- 1939-02-21 FR FR850637D patent/FR850637A/en not_active Expired
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3059060A (en) * | 1956-12-14 | 1962-10-16 | Int Standard Electric Corp | Electric signalling circuits |
GB2139055A (en) * | 1983-04-28 | 1984-10-31 | Darome Inc | Automatic nulling teleconferencing circuit |
Also Published As
Publication number | Publication date |
---|---|
FR850637A (en) | 1939-12-21 |
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