GB1400630A - Telecommunications exchange systems - Google Patents
Telecommunications exchange systemsInfo
- Publication number
- GB1400630A GB1400630A GB4935572A GB4935572A GB1400630A GB 1400630 A GB1400630 A GB 1400630A GB 4935572 A GB4935572 A GB 4935572A GB 4935572 A GB4935572 A GB 4935572A GB 1400630 A GB1400630 A GB 1400630A
- Authority
- GB
- United Kingdom
- Prior art keywords
- contact
- relay
- digit
- frequency
- exchange
- 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
- 230000005540 biological transmission Effects 0.000 abstract 1
- 238000001514 detection method Methods 0.000 abstract 1
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
- H04Q1/46—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies comprising means for distinguishing between a signalling current of predetermined frequency and a complex current containing that frequency, e.g. speech current
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Telephone Function (AREA)
- Telephonic Communication Services (AREA)
- Mobile Radio Communication Systems (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19712154078 DE2154078C3 (de) | 1971-10-29 | 1971-10-29 | Schaltungsanordnung für sprachgeschützte frequenzselektive Wählkennzeichenempfänger in Fernmelde-, insbesondere Fernsprechanlagen |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB1400630A true GB1400630A (en) | 1975-07-16 |
Family
ID=5823799
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB4935572A Expired GB1400630A (en) | 1971-10-29 | 1972-10-26 | Telecommunications exchange systems |
Country Status (10)
-
1971
- 1971-10-29 DE DE19712154078 patent/DE2154078C3/de not_active Expired
-
1972
- 1972-09-27 AT AT830572A patent/AT323242B/de not_active IP Right Cessation
- 1972-10-03 CH CH545568D patent/CH545568A/xx not_active IP Right Cessation
- 1972-10-26 IT IT3095672A patent/IT969934B/it active
- 1972-10-26 GB GB4935572A patent/GB1400630A/en not_active Expired
- 1972-10-27 SE SE1395772A patent/SE377417B/xx unknown
- 1972-10-27 BE BE790656A patent/BE790656A/xx unknown
- 1972-10-27 LU LU66383D patent/LU66383A1/xx unknown
- 1972-10-27 FR FR7238205A patent/FR2159024A5/fr not_active Expired
- 1972-10-27 NL NL7214616A patent/NL7214616A/xx not_active Application Discontinuation
Also Published As
| Publication number | Publication date |
|---|---|
| SE377417B (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) | 1975-06-30 |
| DE2154078A1 (de) | 1973-05-03 |
| DE2154078B2 (de) | 1978-11-16 |
| CH545568A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) | 1974-01-31 |
| LU66383A1 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) | 1973-01-23 |
| NL7214616A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) | 1973-05-02 |
| AT323242B (de) | 1975-06-25 |
| FR2159024A5 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) | 1973-06-15 |
| DE2154078C3 (de) | 1979-07-19 |
| IT969934B (it) | 1974-04-10 |
| BE790656A (fr) | 1973-04-27 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PS | Patent sealed | ||
| PCNP | Patent ceased through non-payment of renewal fee |