GB660686A - Improvements relating to telephone circuit signalling apparatus - Google Patents
Improvements relating to telephone circuit signalling apparatusInfo
- Publication number
- GB660686A GB660686A GB2494/49A GB249449A GB660686A GB 660686 A GB660686 A GB 660686A GB 2494/49 A GB2494/49 A GB 2494/49A GB 249449 A GB249449 A GB 249449A GB 660686 A GB660686 A GB 660686A
- Authority
- GB
- United Kingdom
- Prior art keywords
- relay
- signal
- rectified
- frequency
- signalling
- 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
- H04Q—SELECTING
- H04Q1/00—Details of selecting apparatus or arrangements
- H04Q1/18—Electrical details
- H04Q1/30—Signalling arrangements; Manipulation of signalling currents
- H04Q1/44—Signalling arrangements; Manipulation of signalling currents using alternate current
- H04Q1/444—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies
- H04Q1/446—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using one signalling frequency
- H04Q1/4465—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using one signalling frequency the same frequency being used for all signalling information, e.g. A.C. nr.9 system
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Interface Circuits In Exchanges (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR660686X | 1948-02-06 |
Publications (1)
Publication Number | Publication Date |
---|---|
GB660686A true GB660686A (en) | 1951-11-14 |
Family
ID=9010404
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB2494/49A Expired GB660686A (en) | 1948-02-06 | 1949-01-28 | Improvements relating to telephone circuit signalling apparatus |
Country Status (2)
Country | Link |
---|---|
FR (1) | FR962322A (ja) |
GB (1) | GB660686A (ja) |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE973493C (de) * | 1950-09-28 | 1960-03-10 | Philips Nv | Einseitenbandtraegerfrequenzfernsprechsystem |
DE939820C (de) * | 1952-05-06 | 1956-03-01 | Siemens Ag | Schaltungsanordnung zum Empfang von Spannungen einer oder mehrerer Signalfrequenzen |
DE958570C (de) * | 1952-11-03 | 1957-02-21 | Standard Elek K Ag | Empfangskanalverstaerker und Signalempfaenger mit gemeinsamer Verstaerkung der Signalfrequenz und des Sprachbandes |
-
0
- FR FR962322D patent/FR962322A/fr not_active Expired
-
1949
- 1949-01-28 GB GB2494/49A patent/GB660686A/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
FR962322A (ja) | 1950-06-07 |
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