ES475995A1 - Circuit arrangements for a calling, door speaking and door opening installation - Google Patents

Circuit arrangements for a calling, door speaking and door opening installation

Info

Publication number
ES475995A1
ES475995A1 ES475995A ES475995A ES475995A1 ES 475995 A1 ES475995 A1 ES 475995A1 ES 475995 A ES475995 A ES 475995A ES 475995 A ES475995 A ES 475995A ES 475995 A1 ES475995 A1 ES 475995A1
Authority
ES
Spain
Prior art keywords
speaking
door
microphone
button
loudspeaker
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
ES475995A
Other languages
Spanish (es)
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.)
S Siedle and Sohne
Original Assignee
S Siedle and Sohne
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 S Siedle and Sohne filed Critical S Siedle and Sohne
Publication of ES475995A1 publication Critical patent/ES475995A1/en
Expired 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)
  • Interconnected Communication Systems, Intercoms, And Interphones (AREA)
  • Fittings On The Vehicle Exterior For Carrying Loads, And Devices For Holding Or Mounting Articles (AREA)

Abstract

Instead of a telephone handset, a free-speaking facility equipped with a microphone loudspeaker is installed at each in-house terminal without the overall wiring of the installation having to be changed. The free- speaking facility is provided with a door opening button (35), a speak button (30), a listen button (31), a microphone amplifier (32) and a loudspeaker amplifier (33). The listen button (31) connects the loudspeaker amplifier (33) into the speaking circuit between the microphone (10) of the door terminal (3) and the microphone loudspeaker (29) of the free-speaking facility so that a direct current flows in the speaking circuit and audio frequency signals modulated upon the direct current on acoustic energisation of the microphone (10) are amplified. The speak button (30) similarly connects the microphone amplifier (32) into the speaking circuit between the in-house terminal and the loudspeaker (9) of the door terminal. A call signal generator (34) in the free- speaking facility is activated by an associated call button (5) at the door terminal.
ES475995A 1977-12-16 1978-12-14 Circuit arrangements for a calling, door speaking and door opening installation Expired ES475995A1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE2756276A DE2756276C3 (en) 1977-12-16 1977-12-16 Circuit arrangement for a call, door intercom and door opener system

Publications (1)

Publication Number Publication Date
ES475995A1 true ES475995A1 (en) 1979-04-16

Family

ID=6026379

Family Applications (1)

Application Number Title Priority Date Filing Date
ES475995A Expired ES475995A1 (en) 1977-12-16 1978-12-14 Circuit arrangements for a calling, door speaking and door opening installation

Country Status (14)

Country Link
BE (1) BE872780A (en)
DE (1) DE2756276C3 (en)
DK (1) DK535478A (en)
ES (1) ES475995A1 (en)
FI (1) FI783834A (en)
FR (1) FR2412126B3 (en)
GB (1) GB2010642B (en)
IS (1) IS2466A7 (en)
IT (1) IT1101562B (en)
LU (1) LU80652A1 (en)
NL (1) NL7812007A (en)
NO (1) NO784143L (en)
PT (1) PT68875A (en)
SE (1) SE7812671L (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
IT1110111B (en) * 1979-01-12 1985-12-23 Acet Srl TWO-WIRE ELECTRIC DOOR ENTRY SYSTEM, SUSCEPTABLE TO USE A PRESSISTING DOOR BELL SYSTEM, WITHOUT THE NEED FOR ADDITIONAL POWER LINES
DE4130101C1 (en) * 1991-09-11 1993-02-04 Ritto-Werk Loh Gmbh & Co Kg, 6342 Haiger, De Door intercom with door-opening button - centrally generates call signal and feeds to individual internal intercoms using circuit including two series-connected Zener diodes and parallel decoupling diode

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE775090A (en) * 1970-11-10 1972-03-01 Citovox Ditta PARLOPHONE INSTALLATION WITH ELECTRIC DOORPHONE AND CONNECTIONS OBTAINED BY TWO CABLES ONLY

Also Published As

Publication number Publication date
DE2756276B2 (en) 1979-10-11
DK535478A (en) 1979-06-17
IS2466A7 (en) 1978-11-24
NL7812007A (en) 1979-06-19
IT7830842A0 (en) 1978-12-14
FR2412126B3 (en) 1981-10-16
IT1101562B (en) 1985-10-07
BE872780A (en) 1979-03-30
FR2412126A1 (en) 1979-07-13
DE2756276C3 (en) 1982-08-12
PT68875A (en) 1979-01-01
GB2010642A (en) 1979-06-27
FI783834A (en) 1979-06-17
GB2010642B (en) 1982-01-20
DE2756276A1 (en) 1979-06-21
SE7812671L (en) 1979-06-17
NO784143L (en) 1979-06-19
LU80652A1 (en) 1979-04-13

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