NL70732C - - Google Patents
Info
- Publication number
- NL70732C NL70732C NL70732DA NL70732C NL 70732 C NL70732 C NL 70732C NL 70732D A NL70732D A NL 70732DA NL 70732 C NL70732 C NL 70732C
- Authority
- NL
- Netherlands
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
- H04Q1/38—Signalling arrangements; Manipulation of signalling currents using combinations of direct currents of different amplitudes or polarities over line conductors or combination of line conductors
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M1/00—Substation equipment, e.g. for use by subscribers
- H04M1/26—Devices for calling a subscriber
- H04M1/515—Devices for calling a subscriber by generating or selecting signals other than trains of pulses of similar shape, or signals other than currents of one or more different frequencies, e.g. generation of dc signals of alternating polarity, coded pulses or impedance dialling
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q1/00—Details of selecting apparatus or arrangements
- H04Q1/18—Electrical details
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Sub-Exchange Stations And Push- Button Telephones (AREA)
- Exchange Systems With Centralized Control (AREA)
- Interface Circuits In Exchanges (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US53346644A | 1944-05-01 | 1944-05-01 |
Publications (1)
Publication Number | Publication Date |
---|---|
NL70732C true NL70732C (da) |
Family
ID=32682661
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
NL70732D NL70732C (da) | 1944-05-01 |
Country Status (3)
Country | Link |
---|---|
FR (1) | FR939058A (da) |
GB (2) | GB598225A (da) |
NL (1) | NL70732C (da) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE967287C (de) * | 1954-04-05 | 1957-10-31 | Siemens Ag | Schaltungsanordnung zur Tastaturwahl bei Fernmeldeanlagen, insbesondere Fernsprechanlagen |
-
0
- NL NL70732D patent/NL70732C/xx active
-
1945
- 1945-03-30 GB GB1974346A patent/GB598225A/en not_active Expired
- 1945-03-30 GB GB812945A patent/GB598188A/en not_active Expired
-
1946
- 1946-03-29 FR FR939058D patent/FR939058A/fr not_active Expired
Also Published As
Publication number | Publication date |
---|---|
GB598225A (en) | 1948-02-12 |
FR939058A (fr) | 1948-11-03 |
GB598188A (en) | 1948-02-12 |