CN2263418Y

CN2263418Y - Wireless intercom

Info

Publication number: CN2263418Y
Application number: CN96236283U
Authority: CN
Inventors: 王恒; 罗涛
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-09-24
Filing date: 1996-09-24
Publication date: 1997-09-24
Anticipated expiration: 2006-09-24

Abstract

The utility model relates to a wireless intercom earphone which is provided with a head wearing earphone body with a microphone. The utility model has the essential structure that an intercom FM emitter is arranged in an earphone cavity connected with the microphone, a stereo FM receiver is arranged in the other earphone cavity, and the receiver is formed by connecting an FM stereo receiving and integrating device 7088, a stereo decoding and integrating device 7040, a low power amplifying and integrating device 7050 and a peripheral element. The utility model can be used as wireless earphones of wireless intercom earphones, learning-aid apparatus, hearing aids, FM stereo radio earphones and audio equipment, and the utility model has the characteristics of one machine with multifunction and good performance.

Description

A kind of wireless talkback earphone

The utility model is a kind of wireless talkback earphone, and it has wireless talkback and transfers stereo receiving function frequently, and it can be used as wireless talkback earphone, learning-aid device, hearing aids, transfers the wireless headset of stereo Radio earphone and stereo set to use frequently.

In prior art, Chinese patent ZL9121944.9 provides a kind of stereo wireless headphone, and it is made up of the f-m stereo acoustic transmitter, the headphone that are arranged on stereo set (as radio-cassette player, television set etc.) output and the f-m stereo acoustic receiver that is arranged on this earphone.The f-m stereo acoustic transmitter can be encoded the binaural signal of stereo set output, make it synthesize one road stereo composite signal, pass through high frequency modulated then, be emitted to the space by antenna again, after the f-m stereo acoustic receiver can be separated the stereo modulation signal that receives the decoding of mediation stereo composite signal, be reduced into the binaural signal, and emit by earphone.This wireless headset has saved line between earphone and the stereo set in the mode of radio transmission and reception, has exempted the puzzlement of earphone line.Its this function is a purpose with the amusement mainly, is the intercommunication function of purpose and do not have concurrently with study, so function is comparatively single.Moreover the stereo reception integrated device CXA1238 that adopts in the receiver does not possess the function of electric tuning and no signal noise elimination, makes tuning difficult adjustment and influences tonequality, and easily produce noise when tuning, so performance is not ideal enough.

The purpose of this utility model is at above-mentioned deficiency, and the wireless talkback earphone of a kind of a tractor serves several purposes, function admirable is provided.

Solution of the present utility model is as follows: it has the headphone body of a band microphone, its key structure is: an intercommunication frequency-modulated transmitter is housed in being connected with the earphone chamber of microphone, in another earphone chamber the stereo fm receiver is housed, this receiver amplifies integrated device 7050 by f-m stereo sound reception integrated device 7088, stereo decoding integrated device 7040, low-power and peripheral cell connects and composes.

By above-mentioned solution as can be seen, the intercommunication frequency-modulated transmitter that is provided with on earphone can be modulated to high frequency with the intercommunication audio signal of microphone output, and be transmitted into the space by antenna, the receiver that is provided with on the earphone can be by the intercommunication FM signal of the tuning the other side's of receiving emission, emit by earphone after low-power is amplified through separating to be in harmonious proportion, thereby realize both sides' intercommunication or hearing-aid function.If the receiver on the earphone is the tranmitting frequency of oneself by tuning aligning, then can realize the function of learning-aid device from saying, listening certainly.Receiver on the described earphone is a kind of f-m stereo acoustic receiver, and it can realize that not only intercommunication receives, and can also realize the stereo reception of wireless frequency modulation, the stereo reception of broadcast modulation of stereo set etc.Therefore, the utility model has been realized a tractor serves several purposes.Simultaneously, the f-m stereo sound reception integrated device 7088 that the utility model adopts has the function of electric tuning and no signal noise elimination, make the utility model tuning fast and accurately, reduced harmonic distortion, and tuning noiselessness, make its serviceability reach comparatively ideal degree.Therefore, superiority of the present utility model is a tractor serves several purposes, function admirable.

Describe its operation principle in detail according to embodiment below.

Fig. 1, monnolithic case structural representation of the present utility model.

Fig. 2, the circuit theory diagrams of intercommunication frequency-modulated transmitter.

Fig. 3, the circuit theory diagrams of f-m stereo acoustic receiver.

Fig. 4, the circuit theory diagrams of f-m stereo acoustic transmitter.

Referring to Fig. 1, the utility model adopts the headphone body of band microphone (5), in auris dextra chamber (4) the intercommunication frequency-modulated transmitter is set, and in left ear chamber (1) the stereo fm receiver is set.The left and right receiver of earphone is provided with in receiver chamber (6), (7).

Referring to Fig. 2, the main body of intercommunication frequency-modulated transmitter is a high-frequency generator (8), microphone (5) joins by current-limiting resistance (9), (10) and capacitance (11) the vibration input with high-frequency generator, and transmitting antenna (12) joins by the oscillation output end of electric capacity and high-frequency generator.When circuit was connected, the oscillator signal that the intercommunication audio signal of microphone output and high-frequency generator produce carried out mixing and reaches the modulation purpose, and is emitted to the space by antenna (12).Metallic elastic head among Fig. 1 is carried band (3) on the arm and be can be used as transmitting antenna (12) among Fig. 2.

Referring to Fig. 3, integrated device IC1 is FM multiplex receiving device TDA7088 among the figure, the f-m stereo acoustical signal that reception antenna (2) receives is amplified by high-frequency amplifier (13) earlier, send into frequency mixer (14) then and carry out mixing from the local oscillation signal of local oscillator (15), their difference signal is that intermediate-freuqncy signal is passed through the output of 7 pin, send into intermediate frequency amplifier and frequency discriminator (16) by 1 pin again and carry out intermediate frequency and amplify and demodulation, the stereo composite signal that restores is exported by 2 pin.Integrated device IC2 is a stereodecoder 7040, the stereo composite signal of IC1 device 2 pin output is sent into 8 pin of IC2 by amplifying stage (17), after amplifying by amplifier (18), sending into decoder (19) again decodes, restore the binaural audio signal, pass through again after the amplification of amplifier (20) from 5 pin, the output of 6 pin.IC3 is a low power amplifier 7050.2,3 pin that the binaural audio signal is sent into device IC3 through volume adjuster (21) carry out the low-power amplification, export left and right receiver to from 6,7 pin then, emit stereo sound.The signal that ifs circuit receives is non-stereo fm signal, and then circuit omits three-dimensional decode procedure automatically.Again referring to Fig. 3, between 4 pin of device IC1,5 pin, be connected to a variable capacitance diode (22), the voltage that changes these variable capacitance diode two ends can change its capacitance, thereby changes the frequency of oscillation of local oscillator (15), reaches the purpose of electric tuning.Button (23), (24) are tuning control buttons, and wherein button (23) is to search for button automatically, it can make tuning by low frequency from trend high frequency search, when running into signal, automatically lock; Button (24) is the return button, and it can make and tuningly turn back to low frequency by high frequency.

In order to realize the wireless receiving between earphone and the stereo set, the stereo fm reflector can adopt the circuit among Fig. 4, and integrated device IC4 is the dedicated devices 1404 of f-m stereo acoustic emission.A stereo set left side, the audio signal of R channel output is passed through L, the R end gives this reflector, by 1 pin and 18 pin of sending into IC4 after the filtering, through low power amplifier (25), (26) after the power amplification, enter and carry out stereo coding in the stereophonic encoder (27) and form one road stereo composite signal, this signal and pilot signal are respectively from 13, the output of 14 pin, mix the back and deliver to modulator (28) from 12 pin, carry out high frequency modulated and form high frequency stereo modulation signal, send into again in the radio frequency amplifier (29) and amplify, be emitted to the space by transmitting antenna (30) then.This stereo fm reflector also can adopt the radiating circuit structure among the prior art ZL9121944.9.

Claims

1, a kind of wireless talkback earphone has the headphone body of a band microphone, it is characterized in that:

A, an intercommunication frequency-modulated transmitter is housed in being connected with the earphone chamber of microphone;

B, in another earphone chamber the stereo fm receiver is housed, this receiver amplifies integrated device 7050 by f-m stereo sound reception integrated device 7088, stereo decoding integrated device 7040, low-power and peripheral cell connects and composes.