JPH02147993U - - Google Patents
Info
- Publication number
- JPH02147993U JPH02147993U JP5573589U JP5573589U JPH02147993U JP H02147993 U JPH02147993 U JP H02147993U JP 5573589 U JP5573589 U JP 5573589U JP 5573589 U JP5573589 U JP 5573589U JP H02147993 U JPH02147993 U JP H02147993U
- Authority
- JP
- Japan
- Prior art keywords
- microphone
- noise
- differential amplifier
- speech
- prevention 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.)
- Pending
Links
- 230000002265 prevention Effects 0.000 claims description 5
- 238000010586 diagram Methods 0.000 description 4
Landscapes
- Telephone Set Structure (AREA)
- Control Of Amplification And Gain Control (AREA)
- Amplifiers (AREA)
Description
第１図は本考案の一実施例による通話機用ノイ
ズ防止回路を備えた送受話器の回路図、第２図は
ノイズ防止回路を備えた送受話器の概略図、第３
図は従来の送受話器の概略図、第４図は従来の送
受話器の回路図である。
１１，３３……通話用マイクロホン、１２……
ノイズ用マイクロホン、１３，３２……スピーカ
、３１……送受話器、４１……受話回路、４２…
…送話回路。
FIG. 1 is a circuit diagram of a handset equipped with a noise prevention circuit for a telephone according to an embodiment of the present invention, FIG. 2 is a schematic diagram of a handset equipped with a noise prevention circuit, and FIG.
The figure is a schematic diagram of a conventional handset, and FIG. 4 is a circuit diagram of the conventional handset. 11, 33...Microphone for calling, 12...
Noise microphone, 13, 32... Speaker, 31... Handset, 41... Receiving circuit, 42...
...Talking circuit.
Claims (1)
ス方式の通信機に用いられるノイズ防止回路であ
つて、 前記通信機の送受話器に通話用マイクロホンの
他に、該通話用マイクロホンに比べて通話音に対
する出力信号のレベルは低いが雑音に対する出力
信号のレベルは実質的に同じノイズ用マイクロホ
ンを設け、前記通話用マイクロホンと前記ノイズ
用マイクロホンとを差動増幅器の２つの入力端子
にそれぞれ接続し、前記２つのマイクロホンから
の出力信号のレベル差に応じた信号を通話信号と
して該差動増幅器から出力するようにしたことを
特徴とする通話機用ノイズ防止回路。[Scope of Claim for Utility Model Registration] A noise prevention circuit used in a duplex type communication device capable of transmitting and receiving simultaneously, the noise prevention circuit including a microphone for communication in a handset of the communication device, in addition to a microphone for communication. A noise microphone is provided in which the level of the output signal relative to the speech sound is lower than that of the speech sound, but the level of the output signal relative to the noise is substantially the same, and the speech microphone and the noise microphone are connected to two input terminals of a differential amplifier. 1. A noise prevention circuit for a telephone set, wherein the differential amplifier is connected to the two microphones, and outputs a signal corresponding to a level difference between the output signals from the two microphones as a speech signal from the differential amplifier.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5573589U JPH02147993U (en) | 1989-05-17 | 1989-05-17 |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5573589U JPH02147993U (en) | 1989-05-17 | 1989-05-17 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH02147993U true JPH02147993U (en) | 1990-12-17 |
Family
ID=31578947
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5573589U Pending JPH02147993U (en) | 1989-05-17 | 1989-05-17 |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02147993U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0543649U (en) * | 1991-11-11 | 1993-06-11 | ソニー株式会社 | Telephone |
| JPH06205092A (en) * | 1992-09-30 | 1994-07-22 | American Teleph & Telegr Co <Att> | Noise erasing telephone receiver |
-
1989
- 1989-05-17 JP JP5573589U patent/JPH02147993U/ja active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0543649U (en) * | 1991-11-11 | 1993-06-11 | ソニー株式会社 | Telephone |
| JPH06205092A (en) * | 1992-09-30 | 1994-07-22 | American Teleph & Telegr Co <Att> | Noise erasing telephone receiver |
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