GB309063A - Improvements in secret electric signalling systems - Google Patents

Improvements in secret electric signalling systems

Info

Publication number
GB309063A
GB309063A GB230/28A GB23028A GB309063A GB 309063 A GB309063 A GB 309063A GB 230/28 A GB230/28 A GB 230/28A GB 23028 A GB23028 A GB 23028A GB 309063 A GB309063 A GB 309063A
Authority
GB
United Kingdom
Prior art keywords
filters
band
bands
frequencies
pass
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
GB230/28A
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.)
AT&T Corp
Original Assignee
Bell Telephone Laboratories Inc
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 NL27077D priority Critical patent/NL27077C/xx
Priority to US240116A priority patent/US1725566A/en
Application filed by Bell Telephone Laboratories Inc filed Critical Bell Telephone Laboratories Inc
Priority to GB230/28A priority patent/GB309063A/en
Priority to DEI36222D priority patent/DE542428C/de
Publication of GB309063A publication Critical patent/GB309063A/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)
  • Reduction Or Emphasis Of Bandwidth Of Signals (AREA)
  • Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
  • Networks Using Active Elements (AREA)
GB230/28A 1927-12-15 1928-01-03 Improvements in secret electric signalling systems Expired GB309063A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
NL27077D NL27077C (enrdf_load_stackoverflow) 1927-12-15
US240116A US1725566A (en) 1927-12-15 1927-12-15 Secret communication system
GB230/28A GB309063A (en) 1927-12-15 1928-01-03 Improvements in secret electric signalling systems
DEI36222D DE542428C (de) 1927-12-15 1928-11-27 Verfahren zur geheimen hochfrequenten UEbermittlung von Nachrichten

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US240116A US1725566A (en) 1927-12-15 1927-12-15 Secret communication system
GB230/28A GB309063A (en) 1927-12-15 1928-01-03 Improvements in secret electric signalling systems

Publications (1)

Publication Number Publication Date
GB309063A true GB309063A (en) 1929-04-03

Family

ID=26235775

Family Applications (1)

Application Number Title Priority Date Filing Date
GB230/28A Expired GB309063A (en) 1927-12-15 1928-01-03 Improvements in secret electric signalling systems

Country Status (4)

Country Link
US (1) US1725566A (enrdf_load_stackoverflow)
DE (1) DE542428C (enrdf_load_stackoverflow)
GB (1) GB309063A (enrdf_load_stackoverflow)
NL (1) NL27077C (enrdf_load_stackoverflow)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2495727A (en) * 1943-01-07 1950-01-31 Hutchinson Henry Parks Speech privacy apparatus
CH246844A (de) * 1945-09-15 1947-01-31 Patelhold Patentverwertung Verfahren und Einrichtung zur Verschleierung von elektrisch übermittelten Sprachnachrichten.
CH248975A (de) * 1946-02-04 1947-05-31 Patelhold Patentverwertung Verfahren und Einrichtung zur Verschleierung der einzelnen Gespräche einer Mehrkanalanlage.
US2574326A (en) * 1947-12-02 1951-11-06 Rca Corp Generating groups of currents
US3183304A (en) * 1962-03-07 1965-05-11 Bell Telephone Labor Inc Sound amplification system
DE1273002B (de) * 1963-09-11 1968-07-18 Siemens Ag Einrichtung zur verschluesselten UEbertragung von Sprachsignalen durch Vertauschung von Teilbaendern
US6047543A (en) * 1996-12-18 2000-04-11 Litex, Inc. Method and apparatus for enhancing the rate and efficiency of gas phase reactions

Also Published As

Publication number Publication date
NL27077C (enrdf_load_stackoverflow)
DE542428C (de) 1932-01-27
US1725566A (en) 1929-08-20

Similar Documents

Publication Publication Date Title
GB532619A (en) Wave transmission networks
GB309063A (en) Improvements in secret electric signalling systems
US1907109A (en) Radio signaling system
GB635707A (en) Method of and arrangement for scrambling signals in multichannel systems
US2766325A (en) Narrow band communication system
US2407260A (en) Privacy system
US1227114A (en) Electrical receiving, translating, or repeating circuit.
US1762984A (en) Secret-communicating system
US2038202A (en) Carrier wave system
US2794854A (en) Multichannel communication system
US2417069A (en) Wave transmission system
US1666651A (en) Plural channel secrecy system
US1662876A (en) Assigitoe
US2276132A (en) Carrier frequency system
GB1170787A (en) Broad-band Signal Transmission Circuits
US1721567A (en) Multiplex radio transmitting system
US1542565A (en) Secret signaling
US1750688A (en) Signaling system
US1565091A (en) Wave-transmission system
US2223084A (en) High frequency system
US1658337A (en) Carrier-wave signaling system
US1762754A (en) Phantom carrier circuit
GB226488A (en) Improvements in secret signalling systems
GB613877A (en) Improvements in or relating to arrangements for the transmission of electric signalsoccupying a wide frequency band
US1858307A (en) Means for compensating for nonlinear distortion in transmission circuits