GB516802A - Improvements in or relating to electrical communication secrecy systems - Google Patents

Improvements in or relating to electrical communication secrecy systems

Info

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
Application number
GB2028938A
Other languages
English (en)
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
STC PLC
Original Assignee
Standard Telephone and Cables PLC
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority to BE435305D priority Critical patent/BE435305A/xx
Application filed by Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Priority to GB2028938A priority patent/GB516802A/en
Priority to FR858757D priority patent/FR858757A/fr
Publication of GB516802A publication Critical patent/GB516802A/en
Expired legal-status Critical Current

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)
GB2028938A 1938-07-08 1938-07-08 Improvements in or relating to electrical communication secrecy systems Expired GB516802A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
BE435305D BE435305A (pm) 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 (pm)
FR (1) FR858757A (pm)
GB (1) GB516802A (pm)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4102521A (en) * 1961-10-20 1978-07-25 Boelkow Entwicklungen Kg System for signal coding

Cited By (1)

* Cited by examiner, † Cited by third party
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 (pm)
FR858757A (fr) 1940-12-03

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