IT1138521B - Telefono ad altoparlante senza trasformatore alimentato dalla linea - Google Patents
Telefono ad altoparlante senza trasformatore alimentato dalla lineaInfo
- Publication number
- IT1138521B IT1138521B IT23673/81A IT2367381A IT1138521B IT 1138521 B IT1138521 B IT 1138521B IT 23673/81 A IT23673/81 A IT 23673/81A IT 2367381 A IT2367381 A IT 2367381A IT 1138521 B IT1138521 B IT 1138521B
- Authority
- IT
- Italy
- Prior art keywords
- line
- speaker telephone
- powered transformer
- transformer
- powered
- Prior art date
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M9/00—Arrangements for interconnection not involving centralised switching
- H04M9/08—Two-way loud-speaking telephone systems with means for conditioning the signal, e.g. for suppressing echoes for one or both directions of traffic
- H04M9/10—Two-way loud-speaking telephone systems with means for conditioning the signal, e.g. for suppressing echoes for one or both directions of traffic with switching of direction of transmission by voice frequency
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Amplifiers (AREA)
- Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US06/182,439 US4385207A (en) | 1980-08-29 | 1980-08-29 | Line powered transformerless loudspeaking telephone |
Publications (2)
Publication Number | Publication Date |
---|---|
IT8123673A0 IT8123673A0 (it) | 1981-08-28 |
IT1138521B true IT1138521B (it) | 1986-09-17 |
Family
ID=22668498
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
IT23673/81A IT1138521B (it) | 1980-08-29 | 1981-08-28 | Telefono ad altoparlante senza trasformatore alimentato dalla linea |
Country Status (16)
Country | Link |
---|---|
US (1) | US4385207A (it) |
JP (1) | JPS5776936A (it) |
AU (1) | AU546508B2 (it) |
BE (1) | BE890109A (it) |
CA (1) | CA1167988A (it) |
CH (1) | CH654156A5 (it) |
DE (1) | DE3133424A1 (it) |
ES (1) | ES8302985A1 (it) |
FR (1) | FR2489632B1 (it) |
GB (1) | GB2083976B (it) |
HK (1) | HK6586A (it) |
IE (1) | IE52201B1 (it) |
IL (2) | IL63653A (it) |
IT (1) | IT1138521B (it) |
NL (1) | NL8104016A (it) |
SE (1) | SE447776B (it) |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4492824A (en) * | 1983-08-11 | 1985-01-08 | At&T Bell Laboratories | Speakerphone linear comparator |
US4831650A (en) * | 1988-05-16 | 1989-05-16 | Palco Telecom, Inc. | Adaptive telephone receive control |
JPH06338934A (ja) * | 1993-05-25 | 1994-12-06 | Exar Corp | 事象駆動型制御回路を有するスピーカーホーン |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS495645B1 (it) * | 1970-02-07 | 1974-02-08 | ||
US3725585A (en) * | 1972-03-21 | 1973-04-03 | Itt | Loudspeaking telephone station circuit |
IT1024530B (it) * | 1974-03-21 | 1978-07-20 | Sits Soc It Telecom Siemens | Circuito telefonico amplificato senza trasformatore |
CA1056970A (en) * | 1977-01-10 | 1979-06-19 | Northern Telecom Limited | Electronic network for telephone set |
DE2807304C2 (de) * | 1978-02-21 | 1982-07-01 | Licentia Patent-Verwaltungs-Gmbh, 6000 Frankfurt | Schaltungsanordnung zum Verstärken eines in einer aus einer Teilnehmeranschlußleitung gespeisten Endstelle einer Fernmeldeanlage erzeugten Signals |
US4303805A (en) * | 1979-05-21 | 1981-12-01 | United Networks, Inc. | Subscriber station network |
-
1980
- 1980-08-25 IL IL63653A patent/IL63653A/xx unknown
- 1980-08-29 US US06/182,439 patent/US4385207A/en not_active Expired - Lifetime
-
1981
- 1981-07-20 CA CA000382019A patent/CA1167988A/en not_active Expired
- 1981-08-21 SE SE8104971A patent/SE447776B/sv not_active IP Right Cessation
- 1981-08-24 DE DE19813133424 patent/DE3133424A1/de active Granted
- 1981-08-25 ES ES504949A patent/ES8302985A1/es not_active Expired
- 1981-08-25 GB GB8125850A patent/GB2083976B/en not_active Expired
- 1981-08-25 IL IL63653A patent/IL63653A0/xx unknown
- 1981-08-25 FR FR8116230A patent/FR2489632B1/fr not_active Expired
- 1981-08-27 BE BE0/205783A patent/BE890109A/fr not_active IP Right Cessation
- 1981-08-27 CH CH5528/81A patent/CH654156A5/de not_active IP Right Cessation
- 1981-08-28 IT IT23673/81A patent/IT1138521B/it active
- 1981-08-28 AU AU74710/81A patent/AU546508B2/en not_active Ceased
- 1981-08-28 NL NL8104016A patent/NL8104016A/nl not_active Application Discontinuation
- 1981-08-28 IE IE1969/81A patent/IE52201B1/en unknown
- 1981-08-28 JP JP56134367A patent/JPS5776936A/ja active Pending
-
1986
- 1986-01-30 HK HK65/86A patent/HK6586A/xx unknown
Also Published As
Publication number | Publication date |
---|---|
FR2489632A1 (fr) | 1982-03-05 |
IE52201B1 (en) | 1987-08-05 |
DE3133424C2 (it) | 1987-10-01 |
SE447776B (sv) | 1986-12-08 |
BE890109A (fr) | 1981-12-16 |
HK6586A (en) | 1986-02-07 |
AU7471081A (en) | 1982-03-04 |
SE8104971L (sv) | 1982-03-01 |
IT8123673A0 (it) | 1981-08-28 |
CH654156A5 (de) | 1986-01-31 |
US4385207A (en) | 1983-05-24 |
IL63653A0 (en) | 1981-11-30 |
DE3133424A1 (de) | 1982-06-16 |
GB2083976B (en) | 1984-05-02 |
FR2489632B1 (fr) | 1985-10-25 |
IL63653A (en) | 1984-05-31 |
ES504949A0 (es) | 1983-02-01 |
ES8302985A1 (es) | 1983-02-01 |
IE811969L (en) | 1982-02-28 |
AU546508B2 (en) | 1985-09-05 |
JPS5776936A (en) | 1982-05-14 |
GB2083976A (en) | 1982-03-31 |
NL8104016A (nl) | 1982-03-16 |
CA1167988A (en) | 1984-05-22 |
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