ES8302937A1 - In-house telephone system with picture transmission - Google Patents

In-house telephone system with picture transmission

Info

Publication number
ES8302937A1
ES8302937A1 ES507959A ES507959A ES8302937A1 ES 8302937 A1 ES8302937 A1 ES 8302937A1 ES 507959 A ES507959 A ES 507959A ES 507959 A ES507959 A ES 507959A ES 8302937 A1 ES8302937 A1 ES 8302937A1
Authority
ES
Spain
Prior art keywords
transmitting
signal
devices
picture
telephone system
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
ES507959A
Other languages
Spanish (es)
Other versions
ES507959A0 (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.)
URMET SpA
Original Assignee
URMET SpA
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 URMET SpA filed Critical URMET SpA
Publication of ES8302937A1 publication Critical patent/ES8302937A1/en
Publication of ES507959A0 publication Critical patent/ES507959A0/en
Granted legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N7/00—Television systems
    • H04N7/18—Closed-circuit television [CCTV] systems, i.e. systems in which the video signal is not broadcast
    • H04N7/183—Closed-circuit television [CCTV] systems, i.e. systems in which the video signal is not broadcast for receiving images from a single remote source
    • H04N7/186—Video door telephones
    • 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)
  • Multimedia (AREA)
  • Interconnected Communication Systems, Intercoms, And Interphones (AREA)
  • Closed-Circuit Television Systems (AREA)

Abstract

An in-house telephone system with picture transmission comprises an external station (PE) with devices for transmitting the voice signal and for generating and transmitting the picture signal, a plurality of internal stations (PI1...PIn), which are equipped in each case with devices for transmitting and receiving the voice signal and with a monitor for reproducing the picture signal, devices for selective calling of the internal stations, devices for controlling an electrically operable lock (SE), a first common conductor pair (Ref1, Ref) connecting the external station (PE) to the internal stations (PI1...PIn) for transmitting the voice signal, a reference signal characterising the value of the feed voltage of the respective monitor (M) and the signal for activation of the electrically operable lock (SE), a second common conductor pair (C+, Rit) for transmitting the picture signal and for feeding the individual monitors (M1...Mn) and a plurality of dial-up lines (N1...Nn) for the selective transmission of a ringing current to the individual internal stations.
ES507959A 1980-12-15 1981-12-14 CITOPHONE INSTALLATION WITH IMAGE TRANSMISSION, WHICH USES FOUR COMMON CONDUCTORS AND ONE SELECT CONDUCTOR FOR EACH INTERIOR LOCATION. Granted ES507959A0 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
IT68903/80A IT1165528B (en) 1980-12-15 1980-12-15 DOOR PHONE SYSTEM WITH IMAGE TRANSMISSION USING FOUR COMMON CONDUCTORS AND A SELECTION CONDUCTOR FOR EACH INTERNAL STATION

Publications (2)

Publication Number Publication Date
ES8302937A1 true ES8302937A1 (en) 1983-01-16
ES507959A0 ES507959A0 (en) 1983-01-16

Family

ID=11310869

Family Applications (1)

Application Number Title Priority Date Filing Date
ES507959A Granted ES507959A0 (en) 1980-12-15 1981-12-14 CITOPHONE INSTALLATION WITH IMAGE TRANSMISSION, WHICH USES FOUR COMMON CONDUCTORS AND ONE SELECT CONDUCTOR FOR EACH INTERIOR LOCATION.

Country Status (4)

Country Link
DE (1) DE3139594A1 (en)
ES (1) ES507959A0 (en)
FR (1) FR2496377A1 (en)
IT (1) IT1165528B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
IT1160803B (en) * 1983-03-11 1987-03-11 Comelit Cie Elettronica Italia PROCEDURE FOR TREATING USEFUL SIGNALS IN A FOUR CONDUCTOR VIDEO DOOR PHONE AND RELATED CIRCUITRY

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1926314A1 (en) * 1969-03-07 1970-11-26 Heider Gmbh Circuit arrangement for combined door intercom and opener systems in multi-apartment buildings
DE2126180A1 (en) * 1970-09-09 1972-03-16 Barbuti O Intercom
DE2165904B1 (en) * 1971-12-31 1973-06-28 Kathrein-Werke Kg, 8200 Rosenheim System for multiple use of signal lines in buildings
DE2306109A1 (en) * 1972-03-23 1973-10-04 Ottorino Barbuti INTERCOM
DE2239053B2 (en) * 1972-08-08 1974-07-25 Kathrein-Werke Kg, 8200 Rosenheim System for the multiple use of signal lines in buildings, with a communal television antenna
FR2214213A1 (en) * 1973-01-11 1974-08-09 Diela Ste Expl Ets
DE2741160C2 (en) * 1977-09-13 1985-05-09 S. Siedle & Söhne Telefon- und Telegrafenwerke GmbH, 7743 Furtwangen Circuit arrangement for a call, intercom and door opener system
IT1117616B (en) * 1979-02-07 1986-02-17 Bpt Spa REFINEMENTS IN VIDEO DOOR PHONES

Also Published As

Publication number Publication date
ES507959A0 (en) 1983-01-16
DE3139594A1 (en) 1982-09-16
FR2496377B1 (en) 1985-03-29
IT8068903A0 (en) 1980-12-15
IT1165528B (en) 1987-04-22
FR2496377A1 (en) 1982-06-18

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