CN1710820A - Two-wive system double-signal transmitting loudspeaker detection control circuit in public broadcasting system - Google Patents

Two-wive system double-signal transmitting loudspeaker detection control circuit in public broadcasting system Download PDF

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Publication number
CN1710820A
CN1710820A CNA2005100139049A CN200510013904A CN1710820A CN 1710820 A CN1710820 A CN 1710820A CN A2005100139049 A CNA2005100139049 A CN A2005100139049A CN 200510013904 A CN200510013904 A CN 200510013904A CN 1710820 A CN1710820 A CN 1710820A
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terminal
carrier signal
capacitor
links
signal
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CNA2005100139049A
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CN100542065C (en
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邵未
张幼东
孙开玉
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MINGZHU ELECTRICAL APPLIANCES CO TIANJIN CITY
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MINGZHU ELECTRICAL APPLIANCES CO TIANJIN CITY
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Publication of CN1710820A publication Critical patent/CN1710820A/en
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Abstract

Through two-wire system, the control circuit transfers 120V constant voltage audio signal and bi-directional carrier control signal at same time. Being corresponding to own filter, each signal is parallel mixed at output end so as to transfer double signals through two-wire system at same time. Audio transformer at terminal part picks up audio signal. Band pass filter of carrier signal at terminal picks up carrier control signal. Rectifier of carrier signal at terminal picks up DC power source. Fault detection and on/off control for tens to hundreds pieces of speaker can be implemented by terminal process circuit to execute relevant commands. The disclosed two-wire system will replace multiple-wire system thoroughly. Advantages are: low cost, easy to be constructed at site, high efficiency and reliability. The invention is especially suitable to schools, Olympic sports ground and gymnasium, railway stations etc.

Description

The loud speaker of two-wire system dual signal transmission detects control circuit in the Public Address system
Technical field:
The present invention relates to a kind of wired public broadcasting transmission line.Specifically, particularly transmit level pressure audio signal, carrier control signal simultaneously in the two-wire system public broadcasting circuit, realize the fault detect and the Push And Release control of loud speaker.
Background technology:
At present, can connect tens of extremely hundreds of loud speakers in known wired Public Address system and form radio networks.General two lead transmission 100V or the 120V level pressure audio signal of adopting is to loud speaker.Be called for short two-wire system.But if in broadcast system, realize the fault detect of loud speaker or the control of Push And Release, at least also to increase by two lead transmission of control signals and power supply, form four-wire system or multiple-way system like this, could realize the fault detect of loud speaker or the control of Push And Release.Adopt the defective of multiple-way system mode to be: to increase the lead of two transmission of control signals and DC power supply in (one) known multiple-way system Public Address system, cable material is doubled, cost is multiplied; (2) in bigger Public Address system such as school, stadiums, building residence broadcasting, subway station, railway station, airport, tens of distances between hundreds of loud speakers and broadcasting equipment can reach hundreds of or thousands of rice, site operation must be distinguished the lead of level pressure audio signal and the lead of transmission of control signals, it does not allow misconnection each other, bring suitable difficulty to site operation undoubtedly, solution is not arranged so far.
Summary of the invention:
The objective of the invention is to develop a kind of loud speaker that is specially adapted to transmit with the two-wire system dual signal in the Public Address system and detect control circuit.Specifically be exactly in two-wire system rated power broadcast circuit, to adopt the frequency separation mode to transmit the carrier signal of rated power broadcast audio signal and tens of KHz, obtain DC power supply after the carrier signal rectification simultaneously, transmission when only can finish rated power broadcast audio signal, two-way carrier signal with two-wire system, and be independent of each other, realize the loud speaker Detection ﹠ Controling of two-wire system dual signal transmission in the Public Address system.
Another object of the present invention is to adopt the loud speaker of two-wire system dual signal transmission to detect control circuit, saved the lead of two pieces transmission of control signals and DC power supply, reduced cost, very be convenient to site operation, increase work efficiency and the reliability of broadcast system.
A further object of the present invention is to adopt the loud speaker of two-wire system dual signal transmission to detect control circuit, can not consider polarity during connecting terminal under the occasion that audio signal is not had phase place require.
The present invention is achieved through the following technical solutions: see accompanying drawing 1 or 2, it comprises carrier signal band stop filter (1), carrier signal band pass filter (2), terminal audio frequency transformer (3), terminal carrier signal rectifier (4), terminal carrier signal band pass filter (5), terminal processes circuit (6), it is characterized in that: the level pressure audio signal is to export by carrier signal band stop filter (1), two-way carrier signal is by carrier signal band pass filter (2) output or input, the corresponding respectively filter (1) separately of each signal, (2), after its output parallel connection with terminal audio frequency transformer (3), terminal carrier signal rectifier (4), each input of terminal carrier signal band pass filter (5) links to each other simultaneously, terminal audio frequency transformer (3) output audio signal, terminal carrier signal band pass filter (5) receives or the feedback carrier signal, terminal carrier signal rectifier (4) output DC source, the control signal that receives is carried out by instruction through terminal processes circuit (6), realizes that the loudspeaker faults with two-wire system transmission dual signal detects and Push And Release control in the Public Address system.
Carrier signal band stop filter (1) comprises inductor A, capacitor B; Carrier signal band pass filter (2) comprises carrier wave coupling transformer C, resonant capacitor D, inductor E; Terminal audio frequency transformer (3) comprises transformer Z; Terminal carrier signal rectifier (4) comprises capacitor F, diode G, diode H, filtering capacitor I; Terminal carrier signal band pass filter (5) comprises carrier wave coupling transformer K, resonant capacitor J; Terminal processes circuit (6) comprises resistor L, voltage-stabiliser tube M, capacitor N, resistor O, diode P, capacitor Q, field effect transistor R, relay S, diode T, field effect transistor U, resistor V, microprocessor W, quartz crystal X; Its circuit connecting relation is that level pressure audio signal one end of input links to each other with capacitor B one end simultaneously with inductor A one end, and the carrier signal two ends link to each other with the elementary two ends of carrier wave coupling transformer C respectively; The inductor A other end, the capacitor B other end, inductor E upper end, audio frequency transformer Z just ultra-Right end, capacitor F upper end and resonant capacitor J upper end link to each other simultaneously, the inductor E other end links to each other with capacitor D upper end, and C utmost point lower end of the capacitor D other end and carrier wave coupling transformer links to each other; The resonant capacitor J other end just links to each other utmost point upper end with carrier wave coupling transformer K, the capacitor F other end links to each other with diode H positive pole simultaneously with diode G negative pole, diode H negative pole and filtering capacitor I one end, K utmost point lower end of carrier wave coupling transformer, resistor L one end, coil one end of diode T negative pole and relay S links to each other simultaneously, C utmost point upper end of the level pressure audio signal other end of input and carrier wave coupling transformer, audio frequency transformer Z is ultra-Left end just, Z ultra-Left end of audio frequency transformer, loud speaker Y one end, diode G positive pole, the filtering capacitor I other end, the source electrode of field effect transistor R, the source electrode of field effect transistor U, resistor O one end, capacitor Q one end, voltage-stabiliser tube M is anodal to link to each other simultaneously with microprocessor W the 8th pin, the resistor L other end links to each other with microprocessor W the 1st pin simultaneously with voltage-stabiliser tube M negative pole, quartz crystal X two ends link to each other with the 3rd pin with microprocessor W the 2nd pin respectively, K utmost point upper end of carrier wave coupling transformer links to each other simultaneously with the drain electrode of capacitor N one end and field effect transistor R, the capacitor N other end links to each other with diode P positive pole simultaneously with the resistor O other end, diode P negative pole links to each other with microprocessor W the 4th pin simultaneously with the capacitor Q other end, the loud speaker Y other end links to each other with resistor V one end simultaneously with switch one end of relay S, Z ultra-Right end of the switch other end and the audio frequency transformer of relay S links to each other, the resistor V other end links to each other with microprocessor W the 5th pin, microprocessor W the 7th pin links to each other with the grid of field effect transistor R, microprocessor W the 6th pin links to each other with the grid of field effect transistor U, and the drain electrode of field effect transistor U links to each other with diode T positive pole simultaneously with the other end of relay S coil.
The audio signal of terminal audio frequency transformer (3) output is connected to loud speaker through relay S; Terminal carrier signal rectifier (4) output DC source; The carrier signal that terminal carrier signal band pass filter (5) is received is delivered to microprocessor W after diode P detection; The carrier signal of feedback is delivered to K the utmost point upper end of carrier wave coupling transformer in the terminal carrier wave band pass filter (5) after field effect transistor R amplifies, finish the transmission of its two-way carrier signal; Microprocessor W is connected to loud speaker through resistor V and finishes fault detect; The Push And Release control signal of loud speaker is amplified pusher motor type relay S through field effect transistor U and is finished.
Be meant 120V level pressure audio signal, two-way carrier signal with the dual signal of two-wire system transmission; The two-way carrier signal of transmission is meant that the carrier signal of carrier signal band pass filter (2) output is received by terminal carrier wave band pass filter (5), and the carrier signal of feedback is sent carrier signal band pass filter (2) two ends back to through terminal carrier wave band pass filter (5); Terminal audio frequency transformer (3), terminal carrier signal rectifier (4), terminal carrier wave band pass filter (5), terminal processes circuit (6) compositing terminal part.
Advantage of the present invention and good effect: in (one) public wired broadcast system between broadcasting equipment and the terminal speaker, only adopt two-wire system transmission 120V level pressure audio signal, transmit modulated carrier control signal, it is undamped each other, realizes that loudspeaker faults detects or Push And Release control.Thoroughly solved the defective of existing multiple-way system; (2) because appearance of the present invention has realized only adopting two-wire system transmission dual signal in broadcast system, construction can be reduced cost, be convenient to very much, particularly can under the occasion that audio signal is not had phase place require, polarity can be do not considered during connecting terminal.
Description of drawings
Accompanying drawing 1 is that the loud speaker of two-wire system dual signal transmission in the Public Address system detects the control circuit block diagram: wherein: the 1st, and the carrier signal band stop filter; The 2nd, the carrier signal band pass filter; The 3rd, the terminal audio frequency transformer; The 4th, terminal carrier signal rectifier; The 5th, terminal carrier signal band pass filter; The 6th, the terminal processes circuit.
Accompanying drawing 2 is that the loud speaker of two-wire system dual signal transmission in the Public Address system detects the control circuit electrical schematic diagram.
Preferred forms
In order to implement the loud speaker Detection ﹠ Controling of two-wire system dual signal transmission in the Public Address system, 1 or 2 be described further in conjunction with the accompanying drawings, (1) carrier signal band stop filter (1), carrier signal band pass filter (2), terminal audio frequency transformer (3), terminal carrier signal rectifier (4), terminal carrier signal band pass filter (5), terminal processes circuit (6), it is characterized in that: the level pressure audio signal is to export by carrier signal band stop filter (1), two-way carrier signal is by carrier signal band pass filter (2) output or input, the corresponding respectively filter (1) separately of each signal, (2), after its output parallel connection with terminal audio frequency transformer (3), terminal carrier signal rectifier (4), each input of terminal carrier signal band pass filter (5) links to each other simultaneously, terminal audio frequency transformer (3) output audio signal, terminal carrier signal band pass filter (5) receives or the feedback carrier signal, terminal carrier signal rectifier (4) output DC source, the control signal that receives is carried out by instruction through terminal processes circuit (6), realizes that the loudspeaker faults with two-wire system transmission dual signal detects and Push And Release control in the Public Address system.(2) goodbye accompanying drawing 2, and carrier signal band stop filter (1) comprises inductor A, capacitor B; Carrier signal band pass filter (2) comprises carrier wave coupling transformer C, resonant capacitor D, inductor E; Terminal audio frequency transformer (3) comprises transformer Z; Terminal carrier signal rectifier (4) comprises capacitor F, diode G, diode H, filtering capacitor I; Terminal carrier signal band pass filter (5) comprises carrier wave coupling transformer K, resonant capacitor J; Terminal processes circuit (6) comprises resistor L, voltage-stabiliser tube M, capacitor N, resistor O, diode P, capacitor Q, field effect transistor R, relay S, diode T, field effect transistor U, resistor V, microprocessor W, quartz crystal X; Its circuit connecting relation is that level pressure audio signal one end of input links to each other with capacitor B one end simultaneously with inductor A one end, and the carrier signal two ends link to each other with the elementary two ends of carrier wave coupling transformer C respectively; The inductor A other end, the capacitor B other end, inductor E upper end, audio frequency transformer Z just ultra-Right end, capacitor F upper end and resonant capacitor J upper end link to each other simultaneously, the inductor E other end links to each other with capacitor D upper end, and C utmost point lower end of the capacitor D other end and carrier wave coupling transformer links to each other; The resonant capacitor J other end just links to each other utmost point upper end with carrier wave coupling transformer K, the capacitor F other end links to each other with diode H positive pole simultaneously with diode G negative pole, diode H negative pole and filtering capacitor I one end, K utmost point lower end of carrier wave coupling transformer, resistor L one end, coil one end of diode T negative pole and relay S links to each other simultaneously, C utmost point upper end of the level pressure audio signal other end of input and carrier wave coupling transformer, audio frequency transformer Z is ultra-Left end just, Z ultra-Left end of audio frequency transformer, loud speaker Y one end, diode G positive pole, the filtering capacitor I other end, the source electrode of field effect transistor R, the source electrode of field effect transistor U, resistor O one end, capacitor Q one end, voltage-stabiliser tube M is anodal to link to each other simultaneously with microprocessor W the 8th pin, the resistor L other end links to each other with microprocessor W the 1st pin simultaneously with voltage-stabiliser tube M negative pole, quartz crystal X two ends link to each other with the 3rd pin with microprocessor W the 2nd pin respectively, K utmost point upper end of carrier wave coupling transformer links to each other simultaneously with the drain electrode of capacitor N one end and field effect transistor R, the capacitor N other end links to each other with diode P positive pole simultaneously with the resistor O other end, diode P negative pole links to each other with microprocessor W the 4th pin simultaneously with the capacitor Q other end, the loud speaker Y other end links to each other with resistor V one end simultaneously with switch one end of relay S, Z ultra-Right end of the switch other end and the audio frequency transformer of relay S links to each other, the resistor V other end links to each other with microprocessor W the 5th pin, microprocessor W the 7th pin links to each other with the grid of field effect transistor R, microprocessor W the 6th pin links to each other with the grid of field effect transistor U, and the drain electrode of field effect transistor U links to each other with diode T positive pole simultaneously with the other end of relay S coil.(3) audio signal of terminal audio frequency transformer (3) output is connected to loud speaker through relay S; Terminal carrier signal rectifier (4) output DC source; The carrier signal that terminal carrier signal band pass filter (5) is received is delivered to microprocessor W after diode P detection; The carrier signal of feedback is delivered to K the utmost point upper end of carrier wave coupling transformer in the terminal carrier wave band pass filter (5) after field effect transistor R amplifies, finish the transmission of its two-way carrier signal; Microprocessor W is connected to loud speaker through resistor V and finishes fault detect; The Push And Release control signal of loud speaker is amplified pusher motor type relay S through field effect transistor U and is finished.(4) audio signal of audio frequency transformer Z output is connected to loud speaker through relay S, and microprocessor W the 6th pin promotes to realize through relay S the Push And Release control of loud speaker after field effect transistor U amplifies by the signal of instruction output; The carrier control signal that is received by K utmost point of carrier wave coupling transformer is coupled through capacitor N, after diode P detection, deliver to microprocessor W the 4th pin again, carried out by instruction by microprocessor W, microprocessor W the 5th pin is finished the fault detect of loud speaker through resistor V under the switch off state of relay S; The carrier signal of feedback is exported by microprocessor W the 7th pin, after amplifying, field effect transistor R delivers to K utmost point upper end of carrier wave coupling transformer, return through resonant capacitor J, inductor E, resonant capacitor D, carrier wave coupling transformer C by the first utmost point of carrier wave coupling transformer K again, realize two-way carrier signal transmission.(5) carrier signal of carrier control signal and feedback should adopt serial data, and terminal part should adopt and receive back feedback mode earlier.(6) requirement of the microprocessor W in the terminal processes circuit (6) is an end power consumption type device.(7) frequency of audio signal should be below 20KHz, and the voltage of audio signal should be below 120V, and the carrier frequency of carrier control signal should be below 100KHz.

Claims (4)

1. the loud speaker of two-wire system dual signal transmission detects control circuit in the Public Address system, it comprises carrier signal band stop filter (1), carrier signal band pass filter (2), terminal audio frequency transformer (3), terminal carrier signal rectifier (4), terminal carrier signal band pass filter (5), terminal processes circuit (6), it is characterized in that: the level pressure audio signal is to export by carrier signal band stop filter (1), two-way carrier signal is by carrier signal band pass filter (2) output or input, the corresponding respectively filter (1) separately of each signal, (2), after its output parallel connection with terminal audio frequency transformer (3), terminal carrier signal rectifier (4), each input of terminal carrier signal band pass filter (5) links to each other simultaneously, terminal audio frequency transformer (3) output audio signal, terminal carrier signal band pass filter (5) receives or the feedback carrier signal, terminal carrier signal rectifier (4) output DC source, the control signal that receives is carried out by instruction through terminal processes circuit (6), realizes that the loudspeaker faults with two-wire system transmission dual signal detects and Push And Release control in the Public Address system.
2. according to the described detection control circuit of claim 1, it is characterized in that: carrier signal band stop filter (1) comprises inductor A, capacitor B; Carrier signal band pass filter (2) comprises carrier wave coupling transformer C, resonant capacitor D, inductor E; Terminal audio frequency transformer (3) comprises transformer Z; Terminal carrier signal rectifier (4) comprises capacitor F, diode G, diode H, filtering capacitor I; Terminal carrier signal band pass filter (5) comprises carrier wave coupling transformer K, resonant capacitor J; Terminal processes circuit (6) comprises resistor L, voltage-stabiliser tube M, capacitor N, resistor O, diode P, capacitor Q, field effect transistor R, relay S, diode T, field effect transistor U, resistor V, microprocessor W, quartz crystal X; Its circuit connecting relation is that level pressure audio signal one end of input links to each other with capacitor B one end simultaneously with inductor A one end, and the carrier signal two ends link to each other with the elementary two ends of carrier wave coupling transformer C respectively; The inductor A other end, the capacitor B other end, inductor E upper end, audio frequency transformer Z just ultra-Right end, capacitor F upper end and resonant capacitor J upper end link to each other simultaneously, the inductor E other end links to each other with capacitor D upper end, and C utmost point lower end of the capacitor D other end and carrier wave coupling transformer links to each other; The resonant capacitor J other end just links to each other utmost point upper end with carrier wave coupling transformer K, the capacitor F other end links to each other with diode H positive pole simultaneously with diode G negative pole, diode H negative pole and filtering capacitor I one end, K utmost point lower end of carrier wave coupling transformer, resistor L one end, coil one end of diode T negative pole and relay S links to each other simultaneously, C utmost point upper end of the level pressure audio signal other end of input and carrier wave coupling transformer, audio frequency transformer Z is ultra-Left end just, Z ultra-Left end of audio frequency transformer, carrier wave coupling transformer K is utmost point lower end just, loud speaker Y one end, diode G positive pole, the filtering capacitor I other end, the source electrode of field effect transistor R, the source electrode of field effect transistor U, resistor O one end, capacitor Q one end, voltage-stabiliser tube M is anodal to link to each other simultaneously with microprocessor W the 8th pin, the resistor L other end links to each other with microprocessor W the 1st pin simultaneously with voltage-stabiliser tube M negative pole, quartz crystal X two ends link to each other with the 3rd pin with microprocessor W the 2nd pin respectively, K utmost point upper end of carrier wave coupling transformer links to each other simultaneously with the drain electrode of capacitor N one end and field effect transistor R, the capacitor N other end links to each other with diode P positive pole simultaneously with the resistor O other end, diode P negative pole links to each other with microprocessor W the 4th pin simultaneously with the capacitor Q other end, the loud speaker Y other end links to each other with resistor V one end simultaneously with switch one end of relay S, Z ultra-Right end of the switch other end and the audio frequency transformer of relay S links to each other, the resistor V other end links to each other with microprocessor W the 5th pin, microprocessor W the 7th pin links to each other with the grid of field effect transistor R, microprocessor W the 6th pin links to each other with the grid of field effect transistor U, and the drain electrode of field effect transistor U links to each other with diode T positive pole simultaneously with the other end of relay S coil.
3. according to the described detection control circuit of claim 1, it is characterized in that: the audio signal of terminal audio frequency transformer (3) output is connected to loud speaker through relay S; Terminal carrier signal rectifier (4) output DC source; The carrier signal that terminal carrier signal band pass filter (5) is received is delivered to microprocessor W after diode P detection; The carrier signal of feedback is delivered to K the utmost point upper end of carrier wave coupling transformer in the terminal carrier wave band pass filter (5) after field effect transistor R amplifies, finish the transmission of its two-way carrier signal; Microprocessor W is connected to loud speaker through resistor V and finishes fault detect; The Push And Release control signal of loud speaker is amplified pusher motor type relay S through field effect transistor U and is finished.
4. according to claim 1 or 3 described detection control circuits, it is characterized in that: be meant 120V level pressure audio signal, two-way carrier signal with the dual signal of two-wire system transmission; The two-way carrier signal of transmission is meant that the carrier signal of carrier signal band pass filter (2) output is received by terminal carrier wave band pass filter (5), and the carrier signal of feedback is sent carrier signal band pass filter (2) two ends back to through terminal carrier wave band pass filter (5); Terminal audio frequency transformer (3), terminal carrier signal rectifier (4), terminal carrier wave band pass filter (5), terminal processes circuit (6) compositing terminal part.
CNB2005100139049A 2005-06-24 2005-06-24 The loud speaker of two-wire system dual signal transmission detects control circuit in the Public Address system Expired - Fee Related CN100542065C (en)

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CNB2005100139049A CN100542065C (en) 2005-06-24 2005-06-24 The loud speaker of two-wire system dual signal transmission detects control circuit in the Public Address system

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CNB2005100139049A CN100542065C (en) 2005-06-24 2005-06-24 The loud speaker of two-wire system dual signal transmission detects control circuit in the Public Address system

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CN1710820A true CN1710820A (en) 2005-12-21
CN100542065C CN100542065C (en) 2009-09-16

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105991335A (en) * 2015-02-25 2016-10-05 邵未 Addressable fault isolation system

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105991335A (en) * 2015-02-25 2016-10-05 邵未 Addressable fault isolation system

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