FR664485A - Improvements to automatic telephone systems - Google Patents

Improvements to automatic telephone systems

Info

Publication number
FR664485A
FR664485A FR664485DA FR664485A FR 664485 A FR664485 A FR 664485A FR 664485D A FR664485D A FR 664485DA FR 664485 A FR664485 A FR 664485A
Authority
FR
France
Prior art keywords
telephone systems
automatic telephone
automatic
systems
telephone
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.)
Thales SA
Original Assignee
Le Materiel Telephonique Thomson CSF
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 Le Materiel Telephonique Thomson CSF filed Critical Le Materiel Telephonique Thomson CSF
Application granted granted Critical
Publication of FR664485A publication Critical patent/FR664485A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q1/00—Details of selecting apparatus or arrangements
    • H04Q1/18—Electrical details
    • H04Q1/30—Signalling arrangements; Manipulation of signalling currents
    • H04Q1/32—Signalling arrangements; Manipulation of signalling currents using trains of dc pulses

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Monitoring And Testing Of Exchanges (AREA)
FR664485D 1928-06-23 1928-11-23 Improvements to automatic telephone systems Expired FR664485A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US287791A US1743708A (en) 1928-06-23 1928-06-23 Telephone system

Publications (1)

Publication Number Publication Date
FR664485A true FR664485A (en) 1929-09-03

Family

ID=23104367

Family Applications (1)

Application Number Title Priority Date Filing Date
FR664485D Expired FR664485A (en) 1928-06-23 1928-11-23 Improvements to automatic telephone systems

Country Status (2)

Country Link
US (1) US1743708A (en)
FR (1) FR664485A (en)

Also Published As

Publication number Publication date
US1743708A (en) 1930-01-14

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