JPH0354498B2 - - Google Patents
Info
- Publication number
- JPH0354498B2 JPH0354498B2 JP57076033A JP7603382A JPH0354498B2 JP H0354498 B2 JPH0354498 B2 JP H0354498B2 JP 57076033 A JP57076033 A JP 57076033A JP 7603382 A JP7603382 A JP 7603382A JP H0354498 B2 JPH0354498 B2 JP H0354498B2
- Authority
- JP
- Japan
- Prior art keywords
- path
- gain
- paths
- amplifier
- variable gain
- 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
- 230000010355 oscillation Effects 0.000 claims description 108
- 230000002265 prevention Effects 0.000 claims description 23
- 230000006835 compression Effects 0.000 claims description 3
- 238000007906 compression Methods 0.000 claims description 3
- 238000011144 upstream manufacturing Methods 0.000 claims description 2
- 238000001514 detection method Methods 0.000 claims 1
- 230000008878 coupling Effects 0.000 description 31
- 238000010168 coupling process Methods 0.000 description 31
- 238000005859 coupling reaction Methods 0.000 description 31
- 230000005236 sound signal Effects 0.000 description 22
- 230000008859 change Effects 0.000 description 14
- 238000000034 method Methods 0.000 description 14
- 238000010586 diagram Methods 0.000 description 10
- 230000005540 biological transmission Effects 0.000 description 5
- 230000000295 complement effect Effects 0.000 description 5
- 230000001276 controlling effect Effects 0.000 description 5
- 239000003990 capacitor Substances 0.000 description 4
- 238000013016 damping Methods 0.000 description 3
- 230000007423 decrease Effects 0.000 description 3
- 230000006872 improvement Effects 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004044 response Effects 0.000 description 3
- 230000002159 abnormal effect Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000001419 dependent effect Effects 0.000 description 2
- 230000014509 gene expression Effects 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 238000005070 sampling Methods 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 230000002238 attenuated effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 230000003071 parasitic effect Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 230000002459 sustained effect Effects 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
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R3/00—Circuits for transducers, loudspeakers or microphones
- H04R3/02—Circuits for transducers, loudspeakers or microphones for preventing acoustic reaction, i.e. acoustic oscillatory feedback
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Interconnected Communication Systems, Intercoms, And Interphones (AREA)
- Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
- Control Of Amplification And Gain Control (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR8109190A FR2505587A1 (fr) | 1981-05-08 | 1981-05-08 | Dispositif destine a eviter des oscillations entretenues genantes dans un systeme boucle |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7717191A Division JPH0662104A (ja) | 1981-05-08 | 1991-03-18 | 拡声電話機 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS57201360A JPS57201360A (en) | 1982-12-09 |
| JPH0354498B2 true JPH0354498B2 (en]) | 1991-08-20 |
Family
ID=9258217
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP57076033A Granted JPS57201360A (en) | 1981-05-08 | 1982-05-08 | Undesired oscillation preventing circuit |
Country Status (3)
| Country | Link |
|---|---|
| US (1) | US4453039A (en]) |
| JP (1) | JPS57201360A (en]) |
| FR (1) | FR2505587A1 (en]) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4629829A (en) * | 1984-12-14 | 1986-12-16 | Motorola, Inc. | Full duplex speakerphone for radio and landline telephones |
| US4879749A (en) * | 1986-06-26 | 1989-11-07 | Audimax, Inc. | Host controller for programmable digital hearing aid system |
| US5219328A (en) * | 1990-01-03 | 1993-06-15 | Cryolife, Inc. | Fibrin sealant delivery method |
| DK169958B1 (da) * | 1992-10-20 | 1995-04-10 | Gn Danavox As | Høreapparat med kompensation for akustisk tilbagekobling |
| GB9522204D0 (en) * | 1995-10-30 | 1996-01-03 | British Broadcasting Corp | Method and apparatus for reduction of unwanted feedback |
| GB0510385D0 (en) | 2005-05-20 | 2005-06-29 | British Broadcasting Corp | Improvements relating to on-channel repeaters |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1156113B (de) * | 1958-02-28 | 1963-10-24 | Siemens Ag | Schaltungsanordnung fuer Fernsprechanlagen mit einer sprachgesteuerten Rueckkopplungssperre |
| GB1349734A (en) * | 1969-11-07 | 1974-04-10 | Post Office | Arrangements for amplifying and reproducing audio frequency signals |
| US3825843A (en) * | 1973-06-08 | 1974-07-23 | Bell Telephone Labor Inc | Selective distortion compensation circuit |
| US4081622A (en) * | 1976-10-29 | 1978-03-28 | Technex International Ltd. | Electronic circuit for a speakerphone |
| NL7612358A (nl) * | 1976-11-08 | 1978-05-10 | Philips Nv | Versterkerinrichting voor akoestische signalen voorzien van middelen voor het onderdrukken van ongewenste stoorsignalen. |
| US4064462A (en) * | 1976-12-29 | 1977-12-20 | Dukane Corporation | Acoustic feedback peak elimination unit |
| US4081620A (en) * | 1977-05-20 | 1978-03-28 | Bell Telephone Laboratories, Incorporated | Sidetone control circuit for a telephone set |
| EP0065335B1 (fr) * | 1981-05-08 | 1984-12-27 | Telecommunications Radioelectriques Et Telephoniques T.R.T. | Dispositif destiné à éviter des oscillations entretenues gênantes dans un système bouclé et poste téléphonique à haut-parleur utilisant ce dispositif |
| US4382398A (en) * | 1981-05-29 | 1983-05-10 | Peavey Electronics Corp. | Method and apparatus for eliminating feedback in stage monitors |
-
1981
- 1981-05-08 FR FR8109190A patent/FR2505587A1/fr active Granted
-
1982
- 1982-04-28 US US06/372,430 patent/US4453039A/en not_active Expired - Fee Related
- 1982-05-08 JP JP57076033A patent/JPS57201360A/ja active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| FR2505587B1 (en]) | 1983-07-08 |
| FR2505587A1 (fr) | 1982-11-12 |
| US4453039A (en) | 1984-06-05 |
| JPS57201360A (en) | 1982-12-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5412734A (en) | Apparatus and method for reducing acoustic feedback | |
| US3920931A (en) | Hearing aid amplifiers employing selective gain control circuits | |
| JPH0823373A (ja) | 通話器回路 | |
| JPH08223089A (ja) | 全２重接続のためのエコーキャンセレーションの方法および装置 | |
| US4490584A (en) | Infrared remote telephone system level control | |
| JP4189042B2 (ja) | 拡声通話機 | |
| JPH0354498B2 (en]) | ||
| US4454384A (en) | Hands free telephone with switchable gain in the two speech signal paths | |
| JPH0662104A (ja) | 拡声電話機 | |
| US4726062A (en) | Duplex hands-free communications circuit | |
| JP2637106B2 (ja) | 音声会議装置 | |
| JPH01212950A (ja) | 電話装置 | |
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| JPS634986B2 (en]) | ||
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| JPH03151746A (ja) | 高齢者用電話機 | |
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| JPH05252253A (ja) | 電話機 | |
| JPH0217981B2 (en]) | ||
| JP3216387B2 (ja) | モニタ用スピーカ付電話のハウリング防止回路 | |
| JPS584864B2 (ja) | 拡声電話装置 | |
| JPS5880912A (ja) | 送話回路 | |
| JPH06252987A (ja) | 音声通信装置 | |
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