GB1253498A - Electronic supervision circuit for telecommunication systems - Google Patents
Electronic supervision circuit for telecommunication systemsInfo
- Publication number
- GB1253498A GB1253498A GB1062870A GB1062870A GB1253498A GB 1253498 A GB1253498 A GB 1253498A GB 1062870 A GB1062870 A GB 1062870A GB 1062870 A GB1062870 A GB 1062870A GB 1253498 A GB1253498 A GB 1253498A
- Authority
- GB
- United Kingdom
- Prior art keywords
- terminals
- transistor
- choke
- march
- hook
- 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
- H04Q3/00—Selecting arrangements
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Interface Circuits In Exchanges (AREA)
- Monitoring And Testing Of Exchanges (AREA)
Abstract
1,253,498. Automatic exchange systems. INTERNATIONAL STANDARD ELECTRIC CORP. 5 March, 1970 [7 March, 1969], No. 10628/70. Heading H4K. A circuit for supervising the state of a line circuit uses four transistors with two 1, 5 connected to the "a" ling through choke 11 and two 3, 6 connected to the "b" line through choke 14. A battery is connected to resistor 15 and to Zener diode 20. The output of the two circuits are connected to detector scanner terminals 7, 8 respectively. The transistor 3 is biased to become conductive or non-conductive dependent on the resistance of the subscriber loop. The transistor 1 is connected to conduct and remain conducting whenever the subscriber loop is closed. Thus signals (0, 0) and (1, 1) at terminals 7, 8 represent on hook and off hook conditions respectively. - An additional recall facility is obtained by operating switch 18 which inserts high resistance 18 in the loop thus turning off transistor 3 and provides signals (1, 0) at terminals 7, 8 of detector scanner. Spurious calling conditions caused by earth faults and short circuits are indicated as (0, 1) at terminals 7, 8.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR6906404A FR2036239A5 (en) | 1969-03-07 | 1969-03-07 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB1253498A true GB1253498A (en) | 1971-11-17 |
Family
ID=9030281
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB1062870A Expired GB1253498A (en) | 1969-03-07 | 1970-03-05 | Electronic supervision circuit for telecommunication systems |
Country Status (4)
| Country | Link |
|---|---|
| DE (1) | DE2009686A1 (en) |
| ES (1) | ES377207A1 (en) |
| FR (1) | FR2036239A5 (en) |
| GB (1) | GB1253498A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2939009A1 (en) * | 1979-09-26 | 1981-04-09 | Siemens AG, 1000 Berlin und 8000 München | CIRCUIT ARRANGEMENT FOR DETERMINING THE SWITCHING STATE OF A SUBSCRIBER CONNECTION LINE IN TELEPHONE SWITCHING SYSTEMS |
-
1969
- 1969-03-07 FR FR6906404A patent/FR2036239A5/fr not_active Expired
-
1970
- 1970-03-02 DE DE19702009686 patent/DE2009686A1/en active Pending
- 1970-03-05 GB GB1062870A patent/GB1253498A/en not_active Expired
- 1970-03-06 ES ES377207A patent/ES377207A1/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| DE2009686A1 (en) | 1970-09-24 |
| ES377207A1 (en) | 1972-06-01 |
| FR2036239A5 (en) | 1970-12-24 |
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