FR514765A - Improvements to calling devices - Google Patents

Improvements to calling devices

Info

Publication number
FR514765A
FR514765A FR514765A FR514765DA FR514765A FR 514765 A FR514765 A FR 514765A FR 514765 A FR514765 A FR 514765A FR 514765D A FR514765D A FR 514765DA FR 514765 A FR514765 A FR 514765A
Authority
FR
France
Prior art keywords
calling devices
calling
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
FR514765A
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.)
Compagnie Francaise Thomson Houston SA
Original Assignee
Compagnie Francaise Thomson Houston SA
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 Compagnie Francaise Thomson Houston SA filed Critical Compagnie Francaise Thomson Houston SA
Application granted granted Critical
Publication of FR514765A publication Critical patent/FR514765A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/26—Devices for calling a subscriber
    • H04M1/30—Devices which can set up and transmit only one digit at a time
    • H04M1/31—Devices which can set up and transmit only one digit at a time by interrupting current to generate trains of pulses; by periodically opening and closing contacts to generate trains of pulses

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Meter Arrangements (AREA)
FR514765A 1919-05-26 1920-04-30 Improvements to calling devices Expired FR514765A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US299960A US1435253A (en) 1919-05-26 1919-05-26 Calling device for an automatic telephone system

Publications (1)

Publication Number Publication Date
FR514765A true FR514765A (en) 1921-03-18

Family

ID=23157063

Family Applications (1)

Application Number Title Priority Date Filing Date
FR514765A Expired FR514765A (en) 1919-05-26 1920-04-30 Improvements to calling devices

Country Status (2)

Country Link
US (1) US1435253A (en)
FR (1) FR514765A (en)

Also Published As

Publication number Publication date
US1435253A (en) 1922-11-14

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