FR725229A - Improvements to telephone systems - Google Patents

Improvements to telephone systems

Info

Publication number
FR725229A
FR725229A FR725229DA FR725229A FR 725229 A FR725229 A FR 725229A FR 725229D A FR725229D A FR 725229DA FR 725229 A FR725229 A FR 725229A
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 FR725229A publication Critical patent/FR725229A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements
    • H04Q3/58—Arrangements providing connection between main exchange and sub-exchange or satellite

Landscapes

  • Physics & Mathematics (AREA)
  • Astronomy & Astrophysics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Telephonic Communication Services (AREA)
  • Devices For Supply Of Signal Current (AREA)
FR725229D 1930-10-24 1931-10-14 Improvements to telephone systems Expired FR725229A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US390868XA 1930-10-24 1930-10-24

Publications (1)

Publication Number Publication Date
FR725229A true FR725229A (en) 1932-05-10

Family

ID=21903593

Family Applications (1)

Application Number Title Priority Date Filing Date
FR725229D Expired FR725229A (en) 1930-10-24 1931-10-14 Improvements to telephone systems

Country Status (2)

Country Link
FR (1) FR725229A (en)
GB (1) GB390868A (en)

Also Published As

Publication number Publication date
GB390868A (en) 1933-04-20

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