GB638911A - Improvements in or relating to privacy equipment for telephone and other communication systems - Google Patents

Improvements in or relating to privacy equipment for telephone and other communication systems

Info

Publication number
GB638911A
GB638911A GB629447A GB629447A GB638911A GB 638911 A GB638911 A GB 638911A GB 629447 A GB629447 A GB 629447A GB 629447 A GB629447 A GB 629447A GB 638911 A GB638911 A GB 638911A
Authority
GB
United Kingdom
Prior art keywords
band
bands
class
signal band
width
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
GB629447A
Other languages
English (en)
Inventor
Harold Jefferson
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.)
Marconis Wireless Telegraph Co Ltd
BAE Systems Electronics Ltd
Original Assignee
Marconis Wireless Telegraph Co Ltd
Marconi Co Ltd
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 FR962063D priority Critical patent/FR962063A/fr
Application filed by Marconis Wireless Telegraph Co Ltd, Marconi Co Ltd filed Critical Marconis Wireless Telegraph Co Ltd
Priority to GB629447A priority patent/GB638911A/en
Publication of GB638911A publication Critical patent/GB638911A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04K—SECRET COMMUNICATION; JAMMING OF COMMUNICATION
    • H04K1/00—Secret communication
    • H04K1/04—Secret communication by frequency scrambling, i.e. by transposing or inverting parts of the frequency band or by inverting the whole band

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)
GB629447A 1947-03-05 1947-03-05 Improvements in or relating to privacy equipment for telephone and other communication systems Expired GB638911A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
FR962063D FR962063A (https=) 1947-03-05
GB629447A GB638911A (en) 1947-03-05 1947-03-05 Improvements in or relating to privacy equipment for telephone and other communication systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB629447A GB638911A (en) 1947-03-05 1947-03-05 Improvements in or relating to privacy equipment for telephone and other communication systems

Publications (1)

Publication Number Publication Date
GB638911A true GB638911A (en) 1950-06-21

Family

ID=9811872

Family Applications (1)

Application Number Title Priority Date Filing Date
GB629447A Expired GB638911A (en) 1947-03-05 1947-03-05 Improvements in or relating to privacy equipment for telephone and other communication systems

Country Status (2)

Country Link
FR (1) FR962063A (https=)
GB (1) GB638911A (https=)

Also Published As

Publication number Publication date
FR962063A (https=) 1950-05-31

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