BE439775A - - Google Patents
Info
- Publication number
- BE439775A BE439775A BE439775DA BE439775A BE 439775 A BE439775 A BE 439775A BE 439775D A BE439775D A BE 439775DA BE 439775 A BE439775 A BE 439775A
- Authority
- BE
- Belgium
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M1/00—Substation equipment, e.g. for use by subscribers
- H04M1/78—Circuit arrangements in which low-frequency speech signals proceed in one direction on the line, while speech signals proceeding in the other direction on the line are modulated on a high-frequency carrier signal
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Mobile Radio Communication Systems (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE216070X | 1939-12-08 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| BE439775A true BE439775A (zh) |
Family
ID=5827288
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| BE439775D BE439775A (zh) | 1939-12-08 |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US2280538A (zh) |
| BE (1) | BE439775A (zh) |
| CH (1) | CH216070A (zh) |
| FR (1) | FR868642A (zh) |
-
0
- BE BE439775D patent/BE439775A/xx unknown
-
1940
- 1940-11-04 CH CH216070D patent/CH216070A/de unknown
- 1940-11-27 US US367416A patent/US2280538A/en not_active Expired - Lifetime
- 1940-12-30 FR FR868642D patent/FR868642A/fr not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| US2280538A (en) | 1942-04-21 |
| FR868642A (fr) | 1942-01-09 |
| CH216070A (de) | 1941-07-31 |