GB291510A - Improvements in or relating to telephone systems - Google Patents

Improvements in or relating to telephone systems

Info

Publication number
GB291510A
GB291510A GB572727A GB572727A GB291510A GB 291510 A GB291510 A GB 291510A GB 572727 A GB572727 A GB 572727A GB 572727 A GB572727 A GB 572727A GB 291510 A GB291510 A GB 291510A
Authority
GB
United Kingdom
Prior art keywords
relay
test
armature
key
line
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
GB572727A
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.)
Associated Telephone and Telegraph Co
Original Assignee
Associated Telephone and Telegraph Co
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 FR636698D priority Critical patent/FR636698A/fr
Priority to NL24569D priority patent/NL24569C/xx
Priority to BE340841D priority patent/BE340841A/xx
Application filed by Associated Telephone and Telegraph Co filed Critical Associated Telephone and Telegraph Co
Priority to GB572727A priority patent/GB291510A/en
Publication of GB291510A publication Critical patent/GB291510A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/22—Arrangements for supervision, monitoring or testing
    • H04M3/26—Arrangements for supervision, monitoring or testing with means for applying test signals or for measuring
    • H04M3/28—Automatic routine testing ; Fault testing; Installation testing; Test methods, test equipment or test arrangements therefor
    • H04M3/30—Automatic routine testing ; Fault testing; Installation testing; Test methods, test equipment or test arrangements therefor for subscriber's lines, for the local loop

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Monitoring And Testing Of Exchanges (AREA)
GB572727A 1927-03-01 1927-03-01 Improvements in or relating to telephone systems Expired GB291510A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
FR636698D FR636698A (forum.php) 1927-03-01
NL24569D NL24569C (forum.php) 1927-03-01
BE340841D BE340841A (forum.php) 1927-03-01
GB572727A GB291510A (en) 1927-03-01 1927-03-01 Improvements in or relating to telephone systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB572727A GB291510A (en) 1927-03-01 1927-03-01 Improvements in or relating to telephone systems

Publications (1)

Publication Number Publication Date
GB291510A true GB291510A (en) 1928-06-01

Family

ID=9801486

Family Applications (1)

Application Number Title Priority Date Filing Date
GB572727A Expired GB291510A (en) 1927-03-01 1927-03-01 Improvements in or relating to telephone systems

Country Status (4)

Country Link
BE (1) BE340841A (forum.php)
FR (1) FR636698A (forum.php)
GB (1) GB291510A (forum.php)
NL (1) NL24569C (forum.php)

Also Published As

Publication number Publication date
NL24569C (forum.php)
FR636698A (forum.php) 1928-04-14
BE340841A (forum.php)

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