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FR2368187A1 - Systeme pa - Google Patents

Systeme pa

Info

Publication number
FR2368187A1
FR2368187A1 FR7730024A FR7730024A FR2368187A1 FR 2368187 A1 FR2368187 A1 FR 2368187A1 FR 7730024 A FR7730024 A FR 7730024A FR 7730024 A FR7730024 A FR 7730024A FR 2368187 A1 FR2368187 A1 FR 2368187A1
Authority
FR
France
Prior art keywords
remote
call
point
power source
remote point
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.)
Withdrawn
Application number
FR7730024A
Other languages
English (en)
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.)
ACET Srl
Original Assignee
ACET Srl
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 ACET Srl filed Critical ACET Srl
Publication of FR2368187A1 publication Critical patent/FR2368187A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M11/00—Telephonic communication systems specially adapted for combination with other electrical systems
    • H04M11/02—Telephonic communication systems specially adapted for combination with other electrical systems with bell or annunciator systems
    • H04M11/025—Door telephones

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Devices For Supply Of Signal Current (AREA)
  • Portable Nailing Machines And Staplers (AREA)
  • Lining Or Joining Of Plastics Or The Like (AREA)
  • Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)

Abstract

Système parlophone, à deux seuls fils communs, caractérisé en ce que l'appel des dérivés s'effectue par une tension à courant continu calibré, relatif aux usagers individuels et cette tension est telle que le courant d'appel actionnant la sonnette ou sonnerie du dérivé est envoyé par une source d'énergie située chez le dérivé, tandis que le circuit de transmission, pour les différentes valeurs de tension, selon le poussoir d'usager actionné, comprend un amplificateur différentiel des transistors, des diodes, deux diodes Zener, un condensateur, des résistances, ainsi qu'une série de résistances ultérieures, connectées avec les poussoirs d'appeL Application pour réaliser des systèmes parlophones à portier électronique, systèmes vidéoparlophones, et semblables.
FR7730024A 1976-10-14 1977-10-06 Systeme pa Withdrawn FR2368187A1 (fr)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
IT2830076A IT1075034B (it) 1976-10-14 1976-10-14 Impianto citofonico,funzionante con due soli fili comuni,fra un posto principale e le varie derivazioni

Publications (1)

Publication Number Publication Date
FR2368187A1 true FR2368187A1 (fr) 1978-05-12

Family

ID=11223316

Family Applications (1)

Application Number Title Priority Date Filing Date
FR7730024A Withdrawn FR2368187A1 (fr) 1976-10-14 1977-10-06 Systeme pa

Country Status (3)

Country Link
ES (1) ES231156Y (fr)
FR (1) FR2368187A1 (fr)
IT (1) IT1075034B (fr)

Also Published As

Publication number Publication date
IT1075034B (it) 1985-04-22
ES231156U (es) 1977-11-16
ES231156Y (es) 1978-04-01

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Legal Events

Date Code Title Description
ST Notification of lapse