GB890454A - Improvements relating to voice-frequency signal detectors - Google Patents
Improvements relating to voice-frequency signal detectorsInfo
- Publication number
- GB890454A GB890454A GB4023659A GB4023659A GB890454A GB 890454 A GB890454 A GB 890454A GB 4023659 A GB4023659 A GB 4023659A GB 4023659 A GB4023659 A GB 4023659A GB 890454 A GB890454 A GB 890454A
- Authority
- GB
- United Kingdom
- Prior art keywords
- way
- voice
- frequency signal
- transformers
- nov
- 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)
- Interconnected Communication Systems, Intercoms, And Interphones (AREA)
Abstract
890,454. Two-way transmissions. ASSOCIATED ELECTRICAL INDUSTRIES Ltd. Nov. 10, 1960 [Nov. 26, 1959], No. 40236/59, Class 40 (4). In an arrangement wherein a two-way line L is coupled by way of transformers T1, T3 with an interposed matching attenuator P1 to a reversible amplifier A and a loud-speaker/ microphone LM and by way of a transformer T2 and a matching attenuator P2 to a V.F. receiver D which is required to respond to a release signal, the V.F. receiver is guarded against operation by speech from the instrument LM by a connection through a resistance R11 which supplies currents in antiphase with those induced through the transformer T2. The transformers T1, T2 are given suitable turn ratios and an adjustable resistance RV is provided to obtain a satisfactory balance at the signalling frequency.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB4023659A GB890454A (en) | 1959-11-26 | 1959-11-26 | Improvements relating to voice-frequency signal detectors |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB4023659A GB890454A (en) | 1959-11-26 | 1959-11-26 | Improvements relating to voice-frequency signal detectors |
Publications (1)
Publication Number | Publication Date |
---|---|
GB890454A true GB890454A (en) | 1962-02-28 |
Family
ID=10413892
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB4023659A Expired GB890454A (en) | 1959-11-26 | 1959-11-26 | Improvements relating to voice-frequency signal detectors |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB890454A (en) |
-
1959
- 1959-11-26 GB GB4023659A patent/GB890454A/en not_active Expired
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