BE437345A - - Google Patents
Info
- Publication number
- BE437345A BE437345A BE437345DA BE437345A BE 437345 A BE437345 A BE 437345A BE 437345D A BE437345D A BE 437345DA BE 437345 A BE437345 A BE 437345A
- Authority
- BE
- Belgium
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M1/00—Substation equipment, e.g. for use by subscribers
- H04M1/66—Substation equipment, e.g. for use by subscribers with means for preventing unauthorised or fraudulent calling
- H04M1/667—Preventing unauthorised calls from a telephone set
- H04M1/67—Preventing unauthorised calls from a telephone set by electronic means
Landscapes
- Engineering & Computer Science (AREA)
- Computer Security & Cryptography (AREA)
- Signal Processing (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| BE881670X | 1939-12-12 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| BE437345A true BE437345A (en:Method) |
Family
ID=3883816
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| BE437345D BE437345A (en:Method) | 1939-12-12 |
Country Status (2)
| Country | Link |
|---|---|
| BE (1) | BE437345A (en:Method) |
| FR (1) | FR881670A (en:Method) |
-
0
- BE BE437345D patent/BE437345A/xx unknown
-
1940
- 1940-12-12 FR FR881670D patent/FR881670A/fr not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| FR881670A (fr) | 1943-05-05 |