IT1078731B - Telephone switching system with contacts for standard lines - has press button switches for relay coils and display giving line number - Google Patents
Telephone switching system with contacts for standard lines - has press button switches for relay coils and display giving line numberInfo
- Publication number
- IT1078731B IT1078731B IT5281775A IT5281775A IT1078731B IT 1078731 B IT1078731 B IT 1078731B IT 5281775 A IT5281775 A IT 5281775A IT 5281775 A IT5281775 A IT 5281775A IT 1078731 B IT1078731 B IT 1078731B
- Authority
- IT
- Italy
- Prior art keywords
- contacts
- switching system
- line number
- press button
- button switches
- Prior art date
Links
Landscapes
- Sub-Exchange Stations And Push- Button Telephones (AREA)
Abstract
A telephone extension is connected to a telephone line which is selected from a number of lines in order to establish communication with a second extension. This is performed by a switching system comprising a number of press buttons with contacts which operate relays to close a pair of contacts in the telephone lines. Each switch displays a number to indicate which telephone line is directly connected by generating a coded signal which is routed to the display. The push buttons have automatic return actions.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| IT5281775A IT1078731B (en) | 1975-12-22 | 1975-12-22 | Telephone switching system with contacts for standard lines - has press button switches for relay coils and display giving line number |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| IT5281775A IT1078731B (en) | 1975-12-22 | 1975-12-22 | Telephone switching system with contacts for standard lines - has press button switches for relay coils and display giving line number |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| IT1078731B true IT1078731B (en) | 1985-05-08 |
Family
ID=11277698
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| IT5281775A IT1078731B (en) | 1975-12-22 | 1975-12-22 | Telephone switching system with contacts for standard lines - has press button switches for relay coils and display giving line number |
Country Status (1)
| Country | Link |
|---|---|
| IT (1) | IT1078731B (en) |
-
1975
- 1975-12-22 IT IT5281775A patent/IT1078731B/en active
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