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
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 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/fr
Priority to DEI38724D priority patent/DE636403C/de
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)
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 (enrdf_load_stackoverflow) 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 (fr) 1928-07-20 1929-07-18 Perfectionnements aux systèmes téléphoniques
DEI38724D DE636403C (de) 1928-07-20 1929-07-19 Schaltungsanordnung fuer Fernsprechanlagen zur Herstellung von verstaerkten oder unverstaerkten Verbindungen zwischen Leitungen

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 (enrdf_load_stackoverflow)
BE (1) BE362519A (enrdf_load_stackoverflow)
DE (1) DE636403C (enrdf_load_stackoverflow)
FR (1) FR680025A (enrdf_load_stackoverflow)
GB (1) GB324328A (enrdf_load_stackoverflow)

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
US1763013A (en) 1930-06-10
USRE19741E (en) 1935-10-22
DE636403C (de) 1936-10-13
FR680025A (fr) 1930-04-24
BE362519A (enrdf_load_stackoverflow)

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