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FR679643A - Improvements to telephone systems - Google Patents

Improvements to telephone systems

Info

Publication number
FR679643A
FR679643A FR679643DA FR679643A FR 679643 A FR679643 A FR 679643A FR 679643D A FR679643D A FR 679643DA FR 679643 A FR679643 A FR 679643A
Authority
FR
France
Prior art keywords
telephone systems
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
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.)
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
Application filed by Associated Telephone and Telegraph Co filed Critical Associated Telephone and Telegraph Co
Application granted granted Critical
Publication of FR679643A publication Critical patent/FR679643A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements
    • H04Q3/0016—Arrangements providing connection between exchanges

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Interface Circuits In Exchanges (AREA)
FR679643D 1928-08-06 1929-07-24 Improvements to telephone systems Expired FR679643A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US297611A US1778204A (en) 1928-08-06 1928-08-06 Telephone system

Publications (1)

Publication Number Publication Date
FR679643A true FR679643A (en) 1930-04-15

Family

ID=23147031

Family Applications (2)

Application Number Title Priority Date Filing Date
FR679643D Expired FR679643A (en) 1928-08-06 1929-07-24 Improvements to telephone systems
FR37249D Expired FR37249E (en) 1928-08-06 1929-07-27 Improvements to telephone systems

Family Applications After (1)

Application Number Title Priority Date Filing Date
FR37249D Expired FR37249E (en) 1928-08-06 1929-07-27 Improvements to telephone systems

Country Status (3)

Country Link
US (1) US1778204A (en)
FR (2) FR679643A (en)
GB (1) GB316931A (en)

Also Published As

Publication number Publication date
US1778204A (en) 1930-10-14
FR37249E (en) 1930-10-25
GB316931A (en) 1930-08-22

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