GB516802A - Improvements in or relating to electrical communication secrecy systems - Google Patents
Improvements in or relating to electrical communication secrecy systemsInfo
- Publication number
- GB516802A GB516802A GB2028938A GB2028938A GB516802A GB 516802 A GB516802 A GB 516802A GB 2028938 A GB2028938 A GB 2028938A GB 2028938 A GB2028938 A GB 2028938A GB 516802 A GB516802 A GB 516802A
- Authority
- GB
- United Kingdom
- Prior art keywords
- input
- rectifier
- condenser
- valve
- frequencies
- 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
- H04K—SECRET COMMUNICATION; JAMMING OF COMMUNICATION
- H04K1/00—Secret communication
- H04K1/02—Secret communication by adding a second signal to make the desired signal unintelligible
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Emergency Protection Circuit Devices (AREA)
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
BE435305D BE435305A (es) | 1938-07-08 | ||
GB2028938A GB516802A (en) | 1938-07-08 | 1938-07-08 | Improvements in or relating to electrical communication secrecy systems |
FR858757D FR858757A (fr) | 1938-07-08 | 1939-07-05 | Systèmes de transmission électriques avec secret |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB2028938A GB516802A (en) | 1938-07-08 | 1938-07-08 | Improvements in or relating to electrical communication secrecy systems |
Publications (1)
Publication Number | Publication Date |
---|---|
GB516802A true GB516802A (en) | 1940-01-11 |
Family
ID=10143512
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB2028938A Expired GB516802A (en) | 1938-07-08 | 1938-07-08 | Improvements in or relating to electrical communication secrecy systems |
Country Status (3)
Country | Link |
---|---|
BE (1) | BE435305A (es) |
FR (1) | FR858757A (es) |
GB (1) | GB516802A (es) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4102521A (en) * | 1961-10-20 | 1978-07-25 | Boelkow Entwicklungen Kg | System for signal coding |
-
0
- BE BE435305D patent/BE435305A/xx unknown
-
1938
- 1938-07-08 GB GB2028938A patent/GB516802A/en not_active Expired
-
1939
- 1939-07-05 FR FR858757D patent/FR858757A/fr not_active Expired
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4102521A (en) * | 1961-10-20 | 1978-07-25 | Boelkow Entwicklungen Kg | System for signal coding |
Also Published As
Publication number | Publication date |
---|---|
BE435305A (es) | |
FR858757A (fr) | 1940-12-03 |
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