FR760420A - Improvements to calling devices - Google Patents

Improvements to calling devices

Info

Publication number
FR760420A
FR760420A FR760420DA FR760420A FR 760420 A FR760420 A FR 760420A FR 760420D A FR760420D A FR 760420DA FR 760420 A FR760420 A FR 760420A
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
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 des Telephones Thomson Houston
Original Assignee
Compagnie des Telephones Thomson Houston
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 des Telephones Thomson Houston filed Critical Compagnie des Telephones Thomson Houston
Application granted granted Critical
Publication of FR760420A publication Critical patent/FR760420A/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
    • H04M1/515—Devices for calling a subscriber by generating or selecting signals other than trains of pulses of similar shape, or signals other than currents of one or more different frequencies, e.g. generation of dc signals of alternating polarity, coded pulses or impedance dialling

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
FR760420D 1932-11-24 1932-11-24 Improvements to calling devices Expired FR760420A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR760420T 1932-11-24

Publications (1)

Publication Number Publication Date
FR760420A true FR760420A (en) 1934-02-22

Family

ID=9169165

Family Applications (1)

Application Number Title Priority Date Filing Date
FR760420D Expired FR760420A (en) 1932-11-24 1932-11-24 Improvements to calling devices

Country Status (1)

Country Link
FR (1) FR760420A (en)

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