GB494099A - Improvements in or relating to telegraph systems - Google Patents

Improvements in or relating to telegraph systems

Info

Publication number
GB494099A
GB494099A GB1112537A GB1112537A GB494099A GB 494099 A GB494099 A GB 494099A GB 1112537 A GB1112537 A GB 1112537A GB 1112537 A GB1112537 A GB 1112537A GB 494099 A GB494099 A GB 494099A
Authority
GB
United Kingdom
Prior art keywords
frequency
oscillator
phase
double
relating
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
GB1112537A
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 BE427593D priority Critical patent/BE427593A/xx
Application filed by Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Priority to GB1112537A priority patent/GB494099A/en
Priority to DEI61105D priority patent/DE737381C/en
Priority to FR836695D priority patent/FR836695A/en
Publication of GB494099A publication Critical patent/GB494099A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/18—Phase-modulated carrier systems, i.e. using phase-shift keying
    • H04L27/22—Demodulator circuits; Receiver circuits
    • H04L27/233—Demodulator circuits; Receiver circuits using non-coherent demodulation
    • H04L27/2332—Demodulator circuits; Receiver circuits using non-coherent demodulation using a non-coherent carrier
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/18—Phase-modulated carrier systems, i.e. using phase-shift keying
    • H04L27/22—Demodulator circuits; Receiver circuits
    • H04L27/227—Demodulator circuits; Receiver circuits using coherent demodulation
    • H04L27/2275—Demodulator circuits; Receiver circuits using coherent demodulation wherein the carrier recovery circuit uses the received modulated signals

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Interface Circuits In Exchanges (AREA)
  • Devices For Supply Of Signal Current (AREA)

Abstract

494,099. Automatic control systems. STANDARD TELEPHONES & CABLES, Ltd., and TERRY, V. J. April 19, 1937, Nos. 11125 and 18437. [Class 38 (iv)] [Also in Group XL] Oscillation - frequency.-A local oscillator V5, V6 is synchronized with incoming carrier signals applied to the bridge B both when the oscillator is in phase with the received signals and also when the phase of the latter has been reversed. To this end a synchronizing current of double frequency is used. Current derived from the received signals through the transformer B is supplied to a frequency-doubling rectifier bridge RB which feeds a circuit L1, C1 tuned to double the carrier frequency and coupled to both grids of the oscillator V5, V6 in parallel.
GB1112537A 1937-04-19 1937-04-19 Improvements in or relating to telegraph systems Expired GB494099A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
BE427593D BE427593A (en) 1937-04-19
GB1112537A GB494099A (en) 1937-04-19 1937-04-19 Improvements in or relating to telegraph systems
DEI61105D DE737381C (en) 1937-04-19 1938-04-15 Circuit arrangement for telegraph systems, in which the change between character and separation pulses and vice versa is transmitted by changing the phase of a carrier current
FR836695D FR836695A (en) 1937-04-19 1938-04-15 Telegraph systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB1112537A GB494099A (en) 1937-04-19 1937-04-19 Improvements in or relating to telegraph systems

Publications (1)

Publication Number Publication Date
GB494099A true GB494099A (en) 1938-10-19

Family

ID=9980494

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1112537A Expired GB494099A (en) 1937-04-19 1937-04-19 Improvements in or relating to telegraph systems

Country Status (4)

Country Link
BE (1) BE427593A (en)
DE (1) DE737381C (en)
FR (1) FR836695A (en)
GB (1) GB494099A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2471319A (en) * 1945-05-07 1949-05-24 Comp Generale Electricite Alternating-current signal transmitting system

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2471319A (en) * 1945-05-07 1949-05-24 Comp Generale Electricite Alternating-current signal transmitting system

Also Published As

Publication number Publication date
BE427593A (en)
FR836695A (en) 1939-01-24
DE737381C (en) 1943-07-12

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