CN208402103U - A kind of feedback interference low distortion audio frequency broadcast system - Google Patents
A kind of feedback interference low distortion audio frequency broadcast system Download PDFInfo
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- CN208402103U CN208402103U CN201820014567.8U CN201820014567U CN208402103U CN 208402103 U CN208402103 U CN 208402103U CN 201820014567 U CN201820014567 U CN 201820014567U CN 208402103 U CN208402103 U CN 208402103U
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Abstract
The utility model discloses a kind of feedback interference low distortion audio frequency broadcast systems, it is characterized by comprising amplifier U2, audio receiving module, the bandwidth-limited circuit being connected with audio receiving module, the resistance R13 being serially connected between 1 pin of amplifier U2 and 3 pins, anode connect with 1 pin of amplifier U2, the polar capacitor C5 that cathode is sequentially connected after polar capacitor C6, potentiometer R15 and resistance R14 with 11 pins of amplifier U2 etc..The utility model the interfering noise outside setting range can be isolated, and effectively eliminate interfering noise, improve communication effect.The utility model can reduce the amplified distortion factor of audio signal, to improve communication effect.The interference signal that the utility model can isolate rear polar circuit and loudspeaker feedback is returned, to improve the stability of audio signal.
Description
Technical field
The utility model relates to a kind of audio system, in particular to a kind of feedback interference low distortion audio frequency broadcast systems.
Background technique
With the continuous development of electronic technology, electronics has been popularized, to bringing great convenience.However
There is also defects for the audio output system that existing electronics uses, i.e. the sound noise of its output is more, and call is not
It is enough clear, largely affect speech quality.
Utility model content
The sound noise exported the purpose of the utility model is to overcome audio output system is more, and call is not enough clearly
Defect provides a kind of feedback interference low distortion audio frequency broadcast system.
The purpose of this utility model is achieved through the following technical solutions: a kind of feedback interference low distortion audio frequency broadcast system,
Including amplifier U2, audio receiving module, the bandwidth-limited circuit being connected with audio receiving module is serially connected in 1 pipe of amplifier U2
Resistance R13 between foot and 3 pins, anode is connect with 1 pin of amplifier U2, cathode is sequentially through polar capacitor C6, potentiometer R15
And the polar capacitor C5 being connected after resistance R14 with 11 pins of amplifier U2, one end connect with 1 pin of amplifier U2, are another
Hold the resistance R17 that connect after resistance R16 with the control terminal of potentiometer R15, one end connect with 3 pins of amplifier U2, the other end
The resistance R11 being connect after resistance R12 with 2 pins of amplifier U2, the low distortion audio amplification electricity being connect with 1 pin of amplifier U2
Road, and the loudspeaker BT being connected with low distortion audio amplifier circuit；2 pins and resistance R17 and resistance of the amplifier U2
The tie point connection of R16,3 pins are connect with bandwidth-limited circuit.
Further, the low distortion audio amplifier circuit includes amplification chip U1, the mistake being connected with amplification chip U1
It is true to adjust circuit, the polar capacitor C7 that anode is connected with 3 pins of amplification chip U1, cathode is grounded, one end and polar capacitor
The anode of C7 is connected, the resistance R18 of another termination power；2 pins of the amplification chip U1 are connected with 1 pin of amplifier U2
It connects, distortion adjusts circuit and then connect with loudspeaker BT.
It includes triode Q1, triode Q2 that the distortion, which adjusts circuit, and anode is connected with the emitter of triode Q2, bears
The polar capacitor pole C9, P that pole is connect with loudspeaker BT is connected with the cathode of polar capacitor C9, the pole N after resistance R22 with three poles
The diode D3 that the collector of pipe Q2 is connected, one end is connected with 2 pins of amplification chip U1, the other end is through potentiometer R20
The resistance R19 being connected afterwards with the emitter of triode Q2, the capacitor C8 being serially connected between the base stage and emitter of triode Q1,
The resistance R21 being serially connected between the collector and emitter of triode Q1, anode be connected with the collector of triode Q1, cathode
The zener diode D2 that the pole polar capacitor C10 and N of ground connection is connected with the collector of triode Q1, the pole P is grounded；It is described
The collector of triode Q1 connects power supply, and emitter is connected with the emitter of triode Q2, the base stage phase of base stage and triode Q2
Connection；7 pins of the amplification chip U1 are connected with the collector of triode Q1, and 6 pins are connected with the base stage of triode Q1
It connects, 4 pins ground connection；The grounded collector of the triode Q2, emitter are connected with the control terminal of potentiometer R20.
The bandwidth-limited circuit includes the second order high-pass filtering circuit being connected with audio receiving module, is serially connected in second order
Second-order low-pass filter circuit between high-pass filtering circuit and 3 pins of amplifier U2.
The second order high-pass filtering circuit includes operational amplifier A1, and one end is connected with audio receiving module, the other end
The capacitor pole C1, P being connected after capacitor C2 with the anode of operational amplifier A1 is grounded after resistance R3, the pole N and capacitor C1 and
The diode D1 that the tie point of capacitor C2 is connected is serially connected between the pole N of diode D1 and the output end of operational amplifier A1
Resistance R2, the resistance R4 and one end that are serially connected between the output end of operational amplifier A1 and the pole P of diode D1 and operation
The resistance R1 that the anode of amplifier A1 is connected, the other end is grounded；The output end and step low-pass of the operational amplifier A1 is filtered
Wave circuit is connected, and cathode is connected with the pole P of diode D1.
The second-order low-pass filter circuit includes operational amplifier A2, and one end is connected with the output end of operational amplifier A1
It connects, the resistance R5 that the other end is connected after resistance R7 with the anode of operational amplifier A2, one end is with resistance R5's and resistance R7
The capacitor C4 that tie point is connected, the other end is connected with the output end of operational amplifier A2, the resistance being in parallel with capacitor C4
R8, capacitor C3, the resistance R6 being in parallel with capacitor C3 that one end is connected with the anode of operational amplifier A2, the other end is grounded,
And the resistance R9 that one end is connected with the output end of operational amplifier A2, the other end is grounded after resistance R10；The operation is put
The cathode of big device A2 is connected with the tie point of resistance R9 and resistance R10, its output end is then connected with 3 pins of amplifier U2.
The centre frequency of the second order high-pass filtering circuit isThe second-order low-pass filter
The centre frequency of circuit is
The gain A of the second order high-pass filtering circuitF1Equal to the gain A of second-order low-pass filter circuitF2, it may be assumed thatThe gain A of the bandwidth-limited circuitF=AF1AF2。
The cutoff frequency of the bandwidth-limited circuit is 300~3000Hz.
The utility model compared with the prior art, have the following advantages that and the utility model has the advantages that
(1) the utility model the interfering noise outside setting range can be isolated, and effectively eliminate interfering noise,
Improve communication effect.
(2) the utility model can reduce the amplified distortion factor of audio signal, to improve communication effect.
(3) interference signal that the utility model can isolate rear polar circuit and loudspeaker feedback is returned, to improve audio
The stability of signal.
Detailed description of the invention
Fig. 1 is the overall structure diagram of the utility model.
Specific embodiment
The utility model is described in further detail below with reference to embodiment, but the embodiments of the present invention is simultaneously
It is without being limited thereto.
Embodiment
As shown in Figure 1, the feedback interference low distortion audio frequency broadcast system of the utility model, including amplifier U2, audio receive
Module, the bandwidth-limited circuit being connected with audio receiving module, the resistance being serially connected between 1 pin of amplifier U2 and 3 pins
R13, anode connect with 1 pin of amplifier U2, cathode sequentially after polar capacitor C6, potentiometer R15 and resistance R14 with amplifier
The polar capacitor C5 that 11 pins of U2 are connected, one end connect with 1 pin of amplifier U2, the other end after resistance R16 with current potential
The resistance R17 of the control terminal connection of device R15, one end connect with 3 pins of amplifier U2, the other end after resistance R12 with amplifier U2
2 pins connection resistance R11, the low distortion audio amplifier circuit being connect with 1 pin of amplifier U2, and with low distortion audio
The loudspeaker BT that amplifying circuit is connected.2 pins of the amplifier U2 are connect with the tie point of resistance R17 and resistance R16,3 manage
Foot is connect with bandwidth-limited circuit.
Specifically, existing antenna can be used for receiving audio signal to realize in the audio receiving module.The band logical
The frequency filtering of filter circuit is 300~3000Hz, effectively can filter interfering noise and retain the audio signal spoken,
To which the sound for exporting the utility model is more clear.
In order to filter interference signal, as shown in Figure 1, the bandwidth-limited circuit includes two to be connected with audio receiving module
Rank high-pass filtering circuit, the second-order low-pass filter circuit being serially connected between second order high-pass filtering circuit and 3 pins of amplifier U2.
Specifically, the second order high-pass filtering circuit includes operational amplifier A1, capacitor C1, capacitor C2, resistance R1, resistance
R2, resistance R3, resistance R4 and diode D1.
When connection, one end of capacitor C1 is connected with audio receiving module, the other end after capacitor C2 with operation amplifier
The anode of device A1 is connected.The pole P of diode D1 is grounded after resistance R3, the pole N is connected with the tie point of capacitor C1 and capacitor C2
It connects.Resistance R2 is serially connected between the pole N of diode D1 and the output end of operational amplifier A1.Resistance R4 is serially connected in operational amplifier
Between the output end of A1 and the pole P of diode D1.One end of resistance R1 is connected with the anode of operational amplifier A1, another termination
Ground.The output end of the operational amplifier A1 is connected with second-order low-pass filter circuit, and cathode is extremely connected with the P of diode D1
It connects.
The audio signal of audio receiving module output inputs to operational amplifier after capacitor C1 and capacitor C2 are filtered
High-pass filter is collectively formed in A1, operational amplifier A1, capacitor C1, capacitor C2, resistance R4 and resistance R3；The operation amplifier
Device A1 is negative-feedback, can be with the gain of stabilizing circuit.The centre frequency of the second order high-pass filtering circuit isIn the present embodiment, the capacitance of capacitor C1 and capacitor C2 are 0.068 μ F, resistance R1 and electricity
The resistance value for hindering R2 is 8.2K Ω；It can be obtained by above-mentioned formula, the centre frequency f of second order high-pass filtering circuit in the present embodiment1
=286Hz.In addition, the model 14001 of diode D1, the resistance value of resistance R4 is 27K Ω, and the resistance value of resistance R3 is 47K Ω, fortune
Calculate the model OP07 of amplifier A1.The audio signal of operational amplifier A1 output is input to second-order low-pass filter circuit.
As shown in Figure 1, the second-order low-pass filter circuit includes operational amplifier A2, resistance R5, resistance R7, resistance R6, electricity
Hinder R8, resistance R9, resistance R10, capacitor C3 and capacitor C4.When specific connection, one end of resistance R5 and operational amplifier A1
Output end be connected, the other end is connected after resistance R7 with the anode of operational amplifier A2.One end of capacitor C4 and resistance
The tie point of R5 and resistance R7 are connected, the other end is connected with the output end of operational amplifier A2.Resistance R8 and capacitor C4 phase
It is in parallel.One end of capacitor C3 is connected with the anode of operational amplifier A2, the other end is grounded.Resistance R6 is in parallel with capacitor C3.
One end of resistance R9 is connected with the output end of operational amplifier A2, the other end is grounded after resistance R10.The operational amplifier
The cathode of A2 is connected with the tie point of resistance R9 and resistance R10, its output end is then connected with 3 pins of amplifier U2.
The audio signal of operational amplifier A1 output inputs to operational amplifier A2, while electricity after resistance R5 and resistance R7
Audio signal can be filtered by holding C3 and capacitor C4；Operational amplifier A2, resistance R5, resistance R7, capacitor C3, resistance R6,
Low-pass filter is collectively formed in capacitor C4 and resistance R8.Operational amplifier A2 is also negative-feedback, can be with the increasing of stabilizing circuit
Benefit.The centre frequency of the second-order low-pass filter circuit isIn the present embodiment, resistance R5 and
The resistance value of resistance R7 is that the capacitance of 8.2K Ω, capacitor C3 and capacitor C4 are 0.0068 μ F；It can be obtained by above-mentioned formula, this reality
Apply the centre frequency f of second-order low-pass filter circuit in example2=2856Hz.In addition, the resistance value of resistance R6 is 10K Ω, resistance R8
Resistance value be 1K Ω, the resistance value of resistance R9 is 27K Ω, and the resistance value of resistance R10 is 47K Ω, the model of operational amplifier A2
OP07。
It is obtained by above-mentioned, the cutoff frequency of the bandwidth-limited circuit of the present embodiment is 286Hz~2856Hz, thus effectively
Interference signal other than one's voice in speech frequency signal is isolated, speech quality is improved.
In addition, the gain A of the second order high-pass filtering circuitF1Equal to the gain A of second-order low-pass filter circuitF2, it may be assumed thatThe gain A of the bandwidth-limited circuitF=AF1AF2。
In addition, the amplifier U2, polar capacitor C5, polar capacitor C6, resistance R17, resistance R16, potentiometer R15 and resistance
An isolation buffers are collectively formed in R14；The isolation buffers can isolate rear class low distortion audio amplifier circuit and loudspeaker
The feedback interference signal of BT, to improve the stability of system.In the present embodiment, the model LM324 of amplifier U2, polarity electricity
The capacitance for holding C5 is 1 μ F, and the capacitance of polar capacitor C6 is 4.7 μ F, and the resistance value of resistance R17 is 10K Ω, and the resistance value of resistance R16 is
The resistance value of 100K Ω, potentiometer R15 are 10K Ω, and the resistance value of resistance R14 is 4.7K Ω, and the resistance value of resistance R12 is 100K Ω, electricity
The resistance value for hindering R11 is 4.7K Ω, and the resistance value of resistance R13 is 22K Ω.Audio signal is exported from 1 pin of amplifier U2 to low distortion
Audio amplifier circuit.
The low distortion audio amplifier circuit includes amplification chip U1, and the distortion being connected with amplification chip U1 adjusts circuit,
The polar capacitor C7 that anode is connected with 3 pins of amplification chip U1, cathode is grounded, one end is connected with the anode of polar capacitor C7
It connects, the resistance R18 of another termination power.2 pins of the amplification chip U1 are connected with the output end of operational amplifier A2, lose
The true circuit that adjusts then is connect with loudspeaker BT.
Polar capacitor C7 can be filtered input voltage, keep amplification chip U1 work more stable；The electricity
Resistance R18 plays partial pressure, and the resistance value of resistance R18 is 10K Ω, and the capacitance of polar capacitor C7 is 0.1 μ F,
In addition, it includes triode Q1, triode Q2, resistance R19, potentiometer R20, zener diode that the distortion, which adjusts circuit,
D2, capacitor C8, resistance R22, polar capacitor C9, polar capacitor C10, resistance R21 and diode D3.
Wherein, the anode of polar capacitor C9 is connected with the emitter of triode Q2, cathode and loudspeaker BT are connect.Two
The pole P of pole pipe D3 is connected with the cathode of polar capacitor C9, the pole N is connected after resistance R22 with the collector of triode Q2.Electricity
Resistance R19 one end be connected with 2 pins of amplification chip U1, the other end after potentiometer R20 with the emitter phase of triode Q2
Connection.Capacitor C8 is serially connected between the base stage and emitter of triode Q1.Resistance R21 is serially connected in the collector and hair of triode Q1
Between emitter-base bandgap grading.The anode of polar capacitor C10 is connected with the collector of triode Q1, cathode is grounded.The pole N of zener diode D2
It is connected with the collector of triode Q1, the pole P ground connection.
The collector of the triode Q1 connects power supply, and emitter is connected with the emitter of triode Q2, base stage and three poles
The base stage of pipe Q2 is connected.7 pins of the amplification chip U1 are connected with the collector of triode Q1,6 pins and triode
The base stage of Q1 is connected, and 4 pins ground connection, 2 pins are connect with 1 pin of amplifier U2.The grounded collector of the triode Q2,
Emitter is connected with the control terminal of potentiometer R20.
Triode Q1 and triode Q2 forms complementary structure, then forms amplification chip in conjunction with potentiometer R20 and resistance R19
The feedback loop of U1, this structure can reduce the distortion that signal occurs in transmission process.Capacitor C8 can be played a filtering role,
Its capacitance is 0.1 μ F.Adjust the gain ranging that the adjustable distortion of potentiometer R20 adjusts circuit.Polar capacitor C10 can be to defeated
Enter voltage to be filtered, zener diode D2 can carry out pressure stabilizing to voltage, to improve the stability of amplification chip U1.The resistance
The resistance value of R19 is 1K Ω, and the resistance value of potentiometer R20 is 20K Ω, and the resistance value of resistance R22 is 10K Ω, and the resistance value of resistance R21 is
The capacitance of 100K Ω, capacitor C8 are 0.1 μ F, and the capacitance of polar capacitor C9 is 4.7 μ F, and the capacitance of polar capacitor C10 is 470 μ F,
The model LM74 of the model 1N4742 of the model 1N4003 of diode D3, zener diode D2, amplification chip U1.
The audio signal of second order high-pass filtering circuit output is input to after amplification chip U1 amplifies processing, from amplification core
6 pins of piece U1 export, and drive the speaker BT sounding again after the triode Q1 and triode Q2 for driving complementation to be arranged.
As described above, the utility model can be realized well.
Claims (8)
1. a kind of feedback interference low distortion audio frequency broadcast system, it is characterised in that: including amplifier U2, audio receiving module, with sound
The bandwidth-limited circuit that frequency receiving module is connected, the resistance R13 being serially connected between 1 pin of amplifier U2 and 3 pins, anode with
Amplifier U2 1 pin connection, cathode sequentially after polar capacitor C6, potentiometer R15 and resistance R14 with 11 pins of amplifier U2
The polar capacitor C5 being connected, one end connect with 1 pin of amplifier U2, control of the other end after resistance R16 with potentiometer R15
The resistance R17 of connection is held, one end is connect with 3 pins of amplifier U2, the other end is connect after resistance R12 with 2 pins of amplifier U2
Resistance R11, the low distortion audio amplifier circuit being connect with 1 pin of amplifier U2, and with low distortion audio amplifier circuit phase
The loudspeaker BT of connection；2 pins of the amplifier U2 are connect with the tie point of resistance R17 and resistance R16,3 pins and band logical are filtered
Wave circuit connection；The low distortion audio amplifier circuit includes amplification chip U1, and the distortion being connected with amplification chip U1 is adjusted
Circuit, the polar capacitor C7 that anode is connected with 3 pins of amplification chip U1, cathode is grounded, one end and polar capacitor C7 are just
Pole is connected, the resistance R18 of another termination power；2 pins of the amplification chip U1 are connected with 1 pin of amplifier U2, lose
The true circuit that adjusts then is connect with loudspeaker BT.
2. a kind of feedback interference low distortion audio frequency broadcast system according to claim 1, it is characterised in that: the distortion is adjusted
Economize on electricity road includes triode Q1, triode Q2, and anode is connected with the emitter of triode Q2, cathode and loudspeaker BT are connect
The polar capacitor pole C9, P is connected with the cathode of polar capacitor C9, the pole N is connected after resistance R22 with the collector of triode Q2
Diode D3, one end is connected with 2 pins of amplification chip U1, transmitting of the other end after potentiometer R20 with triode Q2
The resistance R19 that pole is connected, the capacitor C8 being serially connected between the base stage and emitter of triode Q1, is serially connected in the collection of triode Q1
Resistance R21 between electrode and emitter, the polar capacitor C10 that anode is connected with the collector of triode Q1, cathode is grounded,
And the pole N is connected with the collector of triode Q1, the zener diode D2 of the pole P ground connection；The collector of the triode Q1 connects
Power supply, emitter are connected with the emitter of triode Q2, and base stage is connected with the base stage of triode Q2；The amplification chip U1
7 pins be connected with the collector of triode Q1,6 pins are connected with the base stage of triode Q1,4 pins ground connection；Described three
The grounded collector of pole pipe Q2, emitter are connected with the control terminal of potentiometer R20.
3. a kind of feedback interference low distortion audio frequency broadcast system according to claim 2, it is characterised in that: the band logical filter
Wave circuit includes the second order high-pass filtering circuit being connected with audio receiving module, is serially connected in second order high-pass filtering circuit and amplifier
Second-order low-pass filter circuit between 3 pins of U2.
4. a kind of feedback interference low distortion audio frequency broadcast system according to claim 3, it is characterised in that: the second order is high
Bandpass filter circuit includes operational amplifier A1, and one end is connected with audio receiving module, the other end is put after capacitor C2 with operation
The capacitor pole C1, P that the anode of big device A1 is connected is grounded after resistance R3, the pole N is connected with the tie point of capacitor C1 and capacitor C2
The diode D1 connect, the resistance R2 being serially connected between the pole N of diode D1 and the output end of operational amplifier A1, is serially connected in operation
Resistance R4 and one end between the output end of amplifier A1 and the pole P of diode D1 are connected with the anode of operational amplifier A1
It connects, the resistance R1 of other end ground connection；The output end of the operational amplifier A1 is connected with second-order low-pass filter circuit, cathode
It is connected with the pole P of diode D1.
5. a kind of feedback interference low distortion audio frequency broadcast system according to claim 4, it is characterised in that: the second order is low
Bandpass filter circuit includes operational amplifier A2, and one end is connected with the output end of operational amplifier A1, the other end is after resistance R7
The resistance R5 being connected with the anode of operational amplifier A2, one end is connected with the tie point of resistance R5 and resistance R7, the other end
The capacitor C4 being connected with the output end of operational amplifier A2, the resistance R8 being in parallel with capacitor C4, one end and operational amplifier
The capacitor C3 that the anode of A2 is connected, the other end is grounded, the resistance R6 being in parallel with capacitor C3 and one end and operational amplifier
The resistance R9 that the output end of A2 is connected, the other end is grounded after resistance R10；The cathode and resistance R9 of the operational amplifier A2
It is connected with the tie point of resistance R10, its output end is then connected with 3 pins of amplifier U2.
6. a kind of feedback interference low distortion audio frequency broadcast system according to claim 5, it is characterised in that: the second order is high
The centre frequency of bandpass filter circuit isThe centre frequency of the second-order low-pass filter circuit is
7. a kind of feedback interference low distortion audio frequency broadcast system according to claim 6, it is characterised in that: the second order is high
The gain A of bandpass filter circuitF1Equal to the gain A of second-order low-pass filter circuitF2, it may be assumed thatThe band
The gain A of bandpass filter circuitF=AF1AF2。
8. a kind of feedback interference low distortion audio frequency broadcast system according to claim 7, it is characterised in that: the band logical filter
The cutoff frequency of wave circuit is 300~3000Hz.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820014567.8U CN208402103U (en) | 2018-01-04 | 2018-01-04 | A kind of feedback interference low distortion audio frequency broadcast system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820014567.8U CN208402103U (en) | 2018-01-04 | 2018-01-04 | A kind of feedback interference low distortion audio frequency broadcast system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN208402103U true CN208402103U (en) | 2019-01-18 |
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ID=65065745
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201820014567.8U Expired - Fee Related CN208402103U (en) | 2018-01-04 | 2018-01-04 | A kind of feedback interference low distortion audio frequency broadcast system |
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| CN (1) | CN208402103U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107948866A (en) * | 2018-01-04 | 2018-04-20 | 成都威邦科技有限公司 | A kind of feedback interference low distortion audio frequency broadcast system |
-
2018
- 2018-01-04 CN CN201820014567.8U patent/CN208402103U/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107948866A (en) * | 2018-01-04 | 2018-04-20 | 成都威邦科技有限公司 | A kind of feedback interference low distortion audio frequency broadcast system |
| CN107948866B (en) * | 2018-01-04 | 2023-09-29 | 成都威邦科技有限公司 | Feedback interference low-distortion audio playing system |
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Granted publication date: 20190118 Termination date: 20200104 |