CH634703A5 - Circuito telefonico elettronico di linea d'utente. - Google Patents

Circuito telefonico elettronico di linea d'utente. Download PDF

Info

Publication number
CH634703A5
CH634703A5 CH479779A CH479779A CH634703A5 CH 634703 A5 CH634703 A5 CH 634703A5 CH 479779 A CH479779 A CH 479779A CH 479779 A CH479779 A CH 479779A CH 634703 A5 CH634703 A5 CH 634703A5
Authority
CH
Switzerland
Prior art keywords
current
transistor
variations
transistors
diodes
Prior art date
Application number
CH479779A
Other languages
English (en)
Italian (it)
Inventor
Flavio Melindo
Original Assignee
Cselt Centro Studi Lab Telecom
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 Cselt Centro Studi Lab Telecom filed Critical Cselt Centro Studi Lab Telecom
Publication of CH634703A5 publication Critical patent/CH634703A5/it

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M19/00—Current supply arrangements for telephone systems
    • H04M19/001—Current supply source at the exchanger providing current to substations
    • H04M19/005—Feeding arrangements without the use of line transformers

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Signal Processing (AREA)
  • Interface Circuits In Exchanges (AREA)
  • Devices For Supply Of Signal Current (AREA)
CH479779A 1978-06-02 1979-05-22 Circuito telefonico elettronico di linea d'utente. CH634703A5 (it)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
IT68269/78A IT1159706B (it) 1978-06-02 1978-06-02 Circuito telefonico elettronico di linea d'utente

Publications (1)

Publication Number Publication Date
CH634703A5 true CH634703A5 (it) 1983-02-15

Family

ID=11308779

Family Applications (1)

Application Number Title Priority Date Filing Date
CH479779A CH634703A5 (it) 1978-06-02 1979-05-22 Circuito telefonico elettronico di linea d'utente.

Country Status (12)

Country Link
US (1) US4287392A ( )
JP (1) JPS5853542B2 ( )
BE (1) BE876692A ( )
BR (1) BR7903166A ( )
CA (1) CA1114084A ( )
CH (1) CH634703A5 ( )
DE (1) DE2922271C2 ( )
FR (1) FR2427751A1 ( )
GB (1) GB2022363B ( )
IT (1) IT1159706B ( )
NL (1) NL7904313A ( )
SE (1) SE7904735L ( )

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2502434A1 (fr) * 1981-03-20 1982-09-24 Trt Telecom Radio Electr Circuit pour reduire la consommation dans un equipement de ligne d'abonne en cas de faux appel
US4473719A (en) * 1982-05-17 1984-09-25 At&T Bell Laboratories Switchhook status detector
DE3237681C2 (de) * 1982-10-12 1986-03-27 Standard Elektrik Lorenz Ag, 7000 Stuttgart Speiseschaltung für einen veränderlichen Verbraucherwiderstand und mit unterschiedlich wirkendem Ausgangswiderstand
JPS59122053U (ja) * 1983-02-03 1984-08-17 エンネツ株式会社 植物栽培用加温機
US4558183A (en) * 1983-10-03 1985-12-10 Cellutron Corporation Opto-coupler interfacing circuit
GB2287155B (en) * 1994-02-23 1998-08-12 Motorola Inc Telecommunications device
CA2146596C (en) * 1994-04-29 1999-09-21 Harry W. Moore, Iii Loop current detector

Family Cites Families (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1199827B (de) * 1964-05-21 1965-09-02 Telefunken Patent Schaltungsanordnung fuer die Speisung der Teilnehmerstellen in Fernmelde-, insbesondere Fernsprechanlagen
US3410961A (en) * 1965-10-12 1968-11-12 Bell Telephone Labor Inc Line circuit for a telephone system having optical solid state means
US3649769A (en) * 1970-10-28 1972-03-14 Gen Electric Circuit for supplying direct current to a telephone line
JPS4950860A ( ) * 1972-09-18 1974-05-17
CH586984A5 ( ) * 1974-12-23 1977-04-15 Ibm
US3783194A (en) * 1972-11-20 1974-01-01 Milgo Electronic Corp Data modem having a fast turn-around time over direct distance dialed networks
US3848094A (en) * 1972-12-29 1974-11-12 Stromberg Carlson Corp Telephone battery feed circuit
FR2216733B1 ( ) * 1973-01-31 1978-05-12 Labo Cent Telecommunicat
FR2254167B2 ( ) * 1973-12-10 1978-08-18 Labo Cent Telecommunicat
FR2254168A1 (en) * 1973-12-11 1975-07-04 Ass Ouvriers Instr Precision Telephone line supply device - is an active electronic device acting as resistance for direct current and high impedance for A.C.
US3914556A (en) * 1974-06-12 1975-10-21 Itt On-hook and off-hook detector for telephone switching systems
US3955052A (en) * 1974-11-18 1976-05-04 Tadiran Israel Electronics Industries Ltd. Subscriber unit particularly useful for time-division-multiplex system
JPS5199408A ( ) * 1975-02-28 1976-09-02 Hitachi Ltd
DE2534609C3 (de) * 1975-08-02 1978-05-18 Telefonbau Und Normalzeit Gmbh, 6000 Frankfurt Schaltungsanordnung für die zentrale Speisung von Teilnehmerstellen in Fernmelde-, insbesondere Fernsprechanlagen
GB1563802A (en) * 1975-11-10 1980-04-02 Post Office Electronic current feed circuit
JPS5267504A (en) * 1975-12-02 1977-06-04 Oki Electric Ind Co Ltd Speaking current supply and supervision system
CH599731A5 ( ) * 1976-03-02 1978-05-31 Ibm
DE2613590C2 (de) * 1976-03-30 1977-10-27 Siemens AG, 1000 Berlin und 8000 München Schaltungsanordnung zur Auswertung von Zustandsänderung auf Leitungen in Fernmelde- insbesondere Fernsprechanlagen
JPS52142905A (en) * 1976-05-24 1977-11-29 Hitachi Denshi Ltd Control device of telephone call current supply
US4087646A (en) * 1977-01-28 1978-05-02 Bell Telephone Laboratories, Incorporated Dual mode telephone subscriber loop current detector
US4142075A (en) * 1977-10-11 1979-02-27 Burr-Brown Research Corporation Interface circuit and method for telephone extension lines
US4228323A (en) * 1979-01-31 1980-10-14 Bell Telephone Laboratories, Incorporated Variable loop length compensated barrier circuit

Also Published As

Publication number Publication date
SE7904735L (sv) 1979-12-03
JPS5853542B2 (ja) 1983-11-30
GB2022363A (en) 1979-12-12
US4287392A (en) 1981-09-01
IT1159706B (it) 1987-03-04
BR7903166A (pt) 1980-01-15
FR2427751A1 (fr) 1979-12-28
GB2022363B (en) 1982-06-16
IT7868269A0 (it) 1978-06-02
JPS54159114A (en) 1979-12-15
DE2922271C2 (de) 1983-02-24
BE876692A (fr) 1979-09-17
NL7904313A (nl) 1979-12-04
CA1114084A (en) 1981-12-08
DE2922271A1 (de) 1979-12-06

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