[go: up one dir, main page]

GB324328A - Improvements in telephone systems - Google Patents

Improvements in telephone systems

Info

Publication number
GB324328A
GB324328A GB21064/28A GB2106428A GB324328A GB 324328 A GB324328 A GB 324328A GB 21064/28 A GB21064/28 A GB 21064/28A GB 2106428 A GB2106428 A GB 2106428A GB 324328 A GB324328 A GB 324328A
Authority
GB
United Kingdom
Prior art keywords
relays
current
frequencies
relay
telephone systems
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
GB21064/28A
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 BE362519D priority Critical patent/BE362519A/xx
Priority to US19741D priority patent/USRE19741E/en
Application filed by Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Priority to GB21064/28A priority patent/GB324328A/en
Priority to US375715A priority patent/US1763013A/en
Priority to FR680025D priority patent/FR680025A/en
Priority to DEI38724D priority patent/DE636403C/en
Publication of GB324328A publication Critical patent/GB324328A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/40—Applications of speech amplifiers

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Interface Circuits In Exchanges (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)

Abstract

324,328. Standard Telephones & Cables, Ltd., and Skillman, T. S. July 20, 1928. Selective distant-control systems.-A series of alternating-current, relays 102 - - 105, Fig. 1, tuned respectively to frequencies W - - Z, control normally-short-circuited direct-current relays 106 - - 109 which in turn control normally operated four-winding relays 110 - - 113, the arrangement being such that any predetermined combination of the frequencies W - -Z effects the release of one only of the relays 110 - - 113. For example, a combination XZ operates relays 103, 105, 107, 109, whereby all windings of relay 110 are deprived of current and this relay releases.
GB21064/28A 1928-07-20 1928-07-20 Improvements in telephone systems Expired GB324328A (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
BE362519D BE362519A (en) 1928-07-20
US19741D USRE19741E (en) 1928-07-20 Telephone system
GB21064/28A GB324328A (en) 1928-07-20 1928-07-20 Improvements in telephone systems
US375715A US1763013A (en) 1928-07-20 1929-07-03 Telephone system
FR680025D FR680025A (en) 1928-07-20 1929-07-18 Improvements to telephone systems
DEI38724D DE636403C (en) 1928-07-20 1929-07-19 Circuit arrangement for telephone systems for the production of reinforced or unreinforced connections between lines

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB21064/28A GB324328A (en) 1928-07-20 1928-07-20 Improvements in telephone systems

Publications (1)

Publication Number Publication Date
GB324328A true GB324328A (en) 1930-01-20

Family

ID=10156588

Family Applications (1)

Application Number Title Priority Date Filing Date
GB21064/28A Expired GB324328A (en) 1928-07-20 1928-07-20 Improvements in telephone systems

Country Status (5)

Country Link
US (2) US1763013A (en)
BE (1) BE362519A (en)
DE (1) DE636403C (en)
FR (1) FR680025A (en)
GB (1) GB324328A (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2601302A (en) * 1941-05-02 1952-06-24 Int Standard Electric Corp Two-way wire telephone repeater circuit
US2564084A (en) * 1946-11-02 1951-08-14 Automatic Elect Lab Telephone system having repeater insertion on long distance lines
US2550755A (en) * 1947-09-24 1951-05-01 Automatic Elect Lab Toll switching telephone system

Also Published As

Publication number Publication date
USRE19741E (en) 1935-10-22
BE362519A (en)
US1763013A (en) 1930-06-10
DE636403C (en) 1936-10-13
FR680025A (en) 1930-04-24

Similar Documents

Publication Publication Date Title
GB788992A (en) Improvements in or relating to telegraph exchange systems
GB324328A (en) Improvements in telephone systems
GB280957A (en)
US2018494A (en) Transmission control circuit
GB1126869A (en) Electromechanical relays
GB225932A (en) Improvements in electric switching apparatus suitable for use in telephony
US1851185A (en) Telephone system
GB197797A (en) Improvements in or relating to telephone systems
US1592903A (en) Interlocking control of a plurality of testing units
US1479430A (en) Telegraph repeater system
GB300586A (en)
GB246544A (en) Improvements in two-way transmission systems with repeaters, particularly for telephone lines
GB358564A (en) Transmission system for telephony or the like
GB237126A (en) Improvements in signalling over telephone and like transmission lines
GB314411A (en) Improvements in relay arrangements particularly for use in automatic or semi-automatic telephone systems
GB207483A (en) Automatic telephone system and switching apparatus therefor
GB493668A (en) Improvements in amplifying devices for use at telephone subscribers' stations
GB304702A (en) Improvements in or relating to telephone systems
GB329637A (en) Improvements in synchronising means for electrical picture receivers and the like
GB302716A (en) Improvements in or relating to automatic or semi-automatic telephone systems
GB396709A (en) Improvements in or relating to terminating circuits for two-way electrical signalling systems
GB296424A (en) Circuit arrangement for double duty selectors in telephone installations
GB208313A (en) Improvements in signalling systems
GB734911A (en) Improvements in or relating to telephone systems
GB295447A (en) Improvements in telephone systems