GB1568329A - Circuit arrangement for loudspeaking telephone set - Google Patents
Circuit arrangement for loudspeaking telephone set Download PDFInfo
- Publication number
- GB1568329A GB1568329A GB6251/78A GB625178A GB1568329A GB 1568329 A GB1568329 A GB 1568329A GB 6251/78 A GB6251/78 A GB 6251/78A GB 625178 A GB625178 A GB 625178A GB 1568329 A GB1568329 A GB 1568329A
- Authority
- GB
- United Kingdom
- Prior art keywords
- channel
- circuit arrangement
- loudspeaker
- transistor
- circuit
- 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
Links
- 239000003990 capacitor Substances 0.000 claims description 15
- 230000000670 limiting effect Effects 0.000 claims description 14
- 230000001105 regulatory effect Effects 0.000 claims description 7
- 230000005669 field effect Effects 0.000 claims description 5
- 230000008901 benefit Effects 0.000 claims description 4
- 230000008054 signal transmission Effects 0.000 claims description 4
- 230000009471 action Effects 0.000 claims description 2
- 230000008878 coupling Effects 0.000 claims description 2
- 238000010168 coupling process Methods 0.000 claims description 2
- 238000005859 coupling reaction Methods 0.000 claims description 2
- 238000005516 engineering process Methods 0.000 claims description 2
- 239000000463 material Substances 0.000 claims description 2
- LJIDRFNRDLYHNC-UHFFFAOYSA-N oleracein E Natural products C1CN2C(=O)CCC2C2=C1C=C(O)C(O)=C2 LJIDRFNRDLYHNC-UHFFFAOYSA-N 0.000 claims description 2
- 239000004065 semiconductor Substances 0.000 claims description 2
- 238000011144 upstream manufacturing Methods 0.000 abstract 1
- 230000009467 reduction Effects 0.000 description 21
- 230000002238 attenuated effect Effects 0.000 description 7
- 230000002829 reductive effect Effects 0.000 description 7
- 230000005540 biological transmission Effects 0.000 description 6
- 230000000694 effects Effects 0.000 description 6
- 230000006978 adaptation Effects 0.000 description 4
- 230000000875 corresponding effect Effects 0.000 description 4
- 238000010276 construction Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000010079 rubber tapping Methods 0.000 description 2
- 230000000903 blocking effect Effects 0.000 description 1
- 230000002596 correlated effect Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
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)
- Interconnected Communication Systems, Intercoms, And Interphones (AREA)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19772751261 DE2751261C3 (de) | 1977-11-16 | 1977-11-16 | Schaltungsanordnung für ein Freisprechertelefon mit selbsttätiger Signalamplitudenbegrenzung |
| DE19772751248 DE2751248C3 (de) | 1977-11-16 | 1977-11-16 | Schaltungsanordnung für ein Freisprechertelefon |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB1568329A true GB1568329A (en) | 1980-05-29 |
Family
ID=25773095
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB6251/78A Expired GB1568329A (en) | 1977-11-16 | 1978-02-16 | Circuit arrangement for loudspeaking telephone set |
Country Status (10)
| Country | Link |
|---|---|
| JP (1) | JPS5472906A (sv) |
| CH (1) | CH626485A5 (sv) |
| DK (1) | DK74878A (sv) |
| FI (1) | FI780555A (sv) |
| FR (1) | FR2409645A2 (sv) |
| GB (1) | GB1568329A (sv) |
| IT (1) | IT1161440B (sv) |
| LU (1) | LU79026A1 (sv) |
| NL (1) | NL7801820A (sv) |
| SE (1) | SE7801902L (sv) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2194868A (en) * | 1986-09-02 | 1988-03-16 | Motorola Inc | Speakerphone with fast idle mode |
| US5544242A (en) * | 1993-05-25 | 1996-08-06 | Exar Corporation | Speakerphone with event driven control circuit |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB8317706D0 (en) * | 1983-06-29 | 1983-08-03 | Standard Telephones Cables Ltd | Telephone subsets |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4051325A (en) * | 1975-01-31 | 1977-09-27 | Matsushita Electric Industrial Co., Ltd. | Speech intercommunication system |
| DE2638286C3 (de) * | 1976-08-25 | 1979-03-01 | Dasy Inter S.A., Genf (Schweiz) | Schaltungsanordnung für ein Freisprechertelefon |
-
1978
- 1978-02-08 LU LU79026A patent/LU79026A1/de unknown
- 1978-02-16 GB GB6251/78A patent/GB1568329A/en not_active Expired
- 1978-02-16 FR FR7804396A patent/FR2409645A2/fr active Pending
- 1978-02-17 NL NL7801820A patent/NL7801820A/xx not_active Application Discontinuation
- 1978-02-20 DK DK74878A patent/DK74878A/da not_active Application Discontinuation
- 1978-02-20 JP JP1840878A patent/JPS5472906A/ja active Pending
- 1978-02-20 IT IT12485/78A patent/IT1161440B/it active
- 1978-02-20 FI FI780555A patent/FI780555A/fi unknown
- 1978-02-20 CH CH182478A patent/CH626485A5/de not_active IP Right Cessation
- 1978-02-20 SE SE7801902A patent/SE7801902L/sv unknown
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2194868A (en) * | 1986-09-02 | 1988-03-16 | Motorola Inc | Speakerphone with fast idle mode |
| GB2194868B (en) * | 1986-09-02 | 1990-10-24 | Motorola Inc | Speakerphone with fast idle mode |
| US5544242A (en) * | 1993-05-25 | 1996-08-06 | Exar Corporation | Speakerphone with event driven control circuit |
Also Published As
| Publication number | Publication date |
|---|---|
| DK74878A (da) | 1979-05-17 |
| CH626485A5 (en) | 1981-11-13 |
| FR2409645A2 (fr) | 1979-06-15 |
| JPS5472906A (en) | 1979-06-11 |
| NL7801820A (nl) | 1979-05-18 |
| FI780555A (fi) | 1979-05-17 |
| SE7801902L (sv) | 1979-05-17 |
| IT7812485A0 (it) | 1978-02-20 |
| IT1161440B (it) | 1987-03-18 |
| LU79026A1 (de) | 1978-06-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US3725585A (en) | Loudspeaking telephone station circuit | |
| US3755625A (en) | Multimicrophone loudspeaking telephone system | |
| US4161624A (en) | Hands-free telephone with cascaded attenuators | |
| CA1215187A (en) | Handsfree circuit for telephone instrument | |
| DE69115794T2 (de) | Anordnung zur Zustandsumschaltung für Lautfernsprechgerät | |
| US3437758A (en) | Conference telephone system | |
| GB2301731A (en) | Speakerphone | |
| RU2143787C1 (ru) | Полудуплексный громкоговоритель с микрофоном | |
| JPS61270961A (ja) | スピ−カ−フオンの利得を制御する方法および装置 | |
| US5838787A (en) | Method and system for controlling echo return loss using a complementary variolosses in transmit path | |
| US3860756A (en) | Automatic voice-path switching circuit for a speaker phone telephone set | |
| US3395255A (en) | Loudspeaking telephone | |
| EP0033744B1 (en) | Voice controlled switching system | |
| JPH04363918A (ja) | 電話装置 | |
| GB1568329A (en) | Circuit arrangement for loudspeaking telephone set | |
| US5193107A (en) | Speakerphone test set | |
| US3610835A (en) | Loudspeaking telephone | |
| EP0187696A2 (en) | Full duplex conferencing system | |
| US3215780A (en) | Loudspeaking intercommunication systems | |
| BG99023A (bg) | Схема за наслагване на слаби,енергитично бедни исилни, енергитично значително по-богати сигнали | |
| US3555190A (en) | Automatic telephone conference connector | |
| GB2110905A (en) | Handsfree telephone facility | |
| EP0361884A2 (en) | Noise reduction in speech transmitter circuits | |
| KR0121115Y1 (ko) | 전화기의 송수화회로 | |
| JP2632316B2 (ja) | 会議電話装置 |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PS | Patent sealed [section 19, patents act 1949] | ||
| PCNP | Patent ceased through non-payment of renewal fee |