FR662634A - Improvements to transmission line checking devices, especially telegraph and telephone lines - Google Patents

Improvements to transmission line checking devices, especially telegraph and telephone lines

Info

Publication number
FR662634A
FR662634A FR662634DA FR662634A FR 662634 A FR662634 A FR 662634A FR 662634D A FR662634D A FR 662634DA FR 662634 A FR662634 A FR 662634A
Authority
FR
France
Prior art keywords
telegraph
transmission line
telephone lines
line checking
checking devices
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
Other languages
French (fr)
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.)
American Electric Power Co Inc
Original Assignee
American Electric Power Co 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
Application filed by American Electric Power Co Inc filed Critical American Electric Power Co Inc
Application granted granted Critical
Publication of FR662634A publication Critical patent/FR662634A/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

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
FR662634D 1927-07-05 1928-07-05 Improvements to transmission line checking devices, especially telegraph and telephone lines Expired FR662634A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US203654A US1778207A (en) 1927-07-05 1927-07-05 Test set

Publications (1)

Publication Number Publication Date
FR662634A true FR662634A (en) 1929-08-09

Family

ID=22754796

Family Applications (1)

Application Number Title Priority Date Filing Date
FR662634D Expired FR662634A (en) 1927-07-05 1928-07-05 Improvements to transmission line checking devices, especially telegraph and telephone lines

Country Status (3)

Country Link
US (1) US1778207A (en)
BE (1) BE352632A (en)
FR (1) FR662634A (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2689885A (en) * 1950-04-11 1954-09-21 Webster Electric Co Inc Transducer
US3173998A (en) * 1960-12-19 1965-03-16 Howard R Deuser Testing equipment for telephone lines

Also Published As

Publication number Publication date
US1778207A (en) 1930-10-14
BE352632A (en)

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