CN2075405U

CN2075405U - Transmitter-receiver for miniature hi-fi sound signal

Info

Publication number: CN2075405U
Application number: CN 90201662
Authority: CN
Inventors: 肖岗; 陈世源
Original assignee: Individual
Current assignee: Individual
Priority date: 1990-02-15
Filing date: 1990-02-15
Publication date: 1991-04-17

Abstract

The utility model relates to a miniature unit which combines a hi-fi FM type sound signal transmitter and an FM receiving earphone. The utility model is composed of a transmitter which converts the sound signals which output by TV sets, recorders, radios and record players to FM waves and an FM miniature receiver which is used for the receiving of transmitting signals of the transmitter in particular. The oscillating frequency of the transmitter can be converted to the same with the operating frequency of a receiver at the time of assembly. The utility model has the advantages of long use, small distortion, convenient use, and can be used by a plurality of people at the same time. The transmitter of the miniature unit can be arranged in the miniature unit, and can be made into a single system of transmitting and receiving.

Description

Transmitter-receiver for miniature hi-fi sound signal

The utility model relates to a kind of miniature Hi-Fi audio signal and transmits, receives the cover machine.It comprises following several characteristic: transmit the audio signal of television set, radio-cassette player, broadcast receiver, phonograph output with audio signal, receive the audio signal of transmitting with miniature reception earphone.

Usually, people in order to prevent to influence other people, all adopt the earphone of band line to be connected with the audio output jack of these equipment at TV reception or when using radio-cassette player, broadcast receiver, phonograph, this has just placed restrictions on listener's scope of activities greatly, and is very inconvenient during use.

On the other hand, to the transformation of above defective, the general employing forwards audio signal by transponder, after receiving with broadcast receiver, audio signal is input to earphone, reaches the purpose of not disturbing other people.

In the prior art, as disclosed a kind of audio signal forwarding, reception programme among the CN2038690U is exactly a typical example, its purpose is with transponder audio signal to be changed into the amplitude-modulated wave signal, utilize broadcast receiver as receiver, realize listening to the purpose of the audio signal of television set, radio-cassette player output.Because this technology is to adopt the amplitude modulation mode that audio signal is modulated on the intermediate frequency carrier to launch, therefore exist audio signal in forwarding and receiving course, be subjected to the restriction of transponder and broadcast receiver bandwidth, fidelity is very poor, and in transmission course defective such as poor anti jamming capability.In addition, with the signal that broadcast receiver receive to be transmitted, also existing needs carry out broadcast receiver tuning, and use for old man and child and make troubles, and because every broadcast receiver only disposes an earphone jack, can not be for defectives such as many people listen to simultaneously.

The purpose of this utility model is to avoid above-mentioned weak point of the prior art, thereby providing a kind of adopts the miniature Hi-Fi audio signal of frequency modulation standard to transmit, receive the cover machine, make it reach the purpose that the audio signal of television set, radio-cassette player, broadcast receiver, phonograph output was transmitted and received to high-quality, and can listen to simultaneously for many people, and easy to use, activity is freely within the specific limits for the listener.

The purpose of this utility model can reach by following measure, form a frequency modulated audio signal transponder by audio frequency input circuit, modulator, LC oscillator, radio frequency output loop, power supply, the audio signal of television set, radio-cassette player, broadcast receiver, phonograph output is delivered to transponder audio frequency input circuit, enter modulator then, the frequency that makes the oscillator signal that the LC oscillator produces is along with the audio signal of input changes, produce the frequency-modulated wave signal, launch by the radio frequency output loop.Miniature reception earphone is made up of FM radio integrated package and peripheral cell, audio frequency output loop, pronunciation device, power supply, after the frequency-modulated wave signal enters the FM radio integrated package by antenna, through frequency conversion, put in the amplitude limit, frequency discrimination, after preposition low the putting with audio signal output to the audio frequency output loop, enter pronunciation device again, realize radio reception.

The purpose of this utility model can also reach by following measure, oscillator in the audio signal transponder adopts crystal oscillator, modulator adopts tuning diode modulator, the radio frequency output loop is launched after adopting frequency doubling technology with the FM signal frequency multiplication, power supply can be used alternating current steady voltage plug, also can be installed in transponder in the television set, need only the receive frequency unanimity of the carrier frequency of adjustment transponder emission when installing, can use for a long time with receiver.Miniature reception earphone can adopt superregenerative FM reception circuit.

The utility model has five accompanying drawings:

Fig. 1 is that cover machine theory diagram is transmitted, received to audio signal.

Fig. 2 is an audio signal transponder theory diagram.

Fig. 3 is miniature reception earphone theory diagram.

Fig. 4 is frequency modulated audio signal transponder embodiment circuit theory diagrams.

Fig. 5 is the miniature reception earphone of frequency modulation embodiment circuit theory diagrams.

Below in conjunction with accompanying drawing the utility model embodiment is further described.

Fig. 1 sound intermediate frequency signal repeater A is made up of the audio frequency input circuit 1 among Fig. 2, modulator 2, oscillator 3, radio frequency output loop 4, power supply 9.Audio frequency input circuit 1 is made up of the CT among Fig. 4, C1, C2, R1, modulator 2 by BG1, C2, C3, R1, R2, form, oscillator 3 is made up of BG1, C2, C3, C4, C5, C6, C8, R2, R3, R4, L1, K12, radio frequency output loop 4 is made up of C5, C6, C7, L1, K12, TX, and power supply 9 is made up of DC1, K11.The trimmer capacitor C6 that connects in the oscillator 3, the frequency when making its work just in time is in the operating frequency range of radio reception integrated package in the miniature reception earphone B, and promptly the frequency of oscillation of using is transferred does not have on the frequency of checking station at 87～108MHZ.Fig. 1 sound intermediate frequency signal micro-receiver B is by FM radio integrated package among Fig. 3 and peripheral cell 5, audio frequency output loop 6, and pronunciation device 7 and power supply 8 are formed.FM radio integrated package and peripheral cell 5 are made up of the IC among Fig. 5, C1, C2, C3, C4, C5, C6, C7, C9, C10, C11, C12, C13, C15, C16, C0, CP, R1, L2, K22, audio frequency output loop 6 is made up of BG2, C17, C18, C19, R2, R3, pronunciation device 7 is made up of EJ, and power supply 8 is made up of DC2, K21.The local oscillation tuning capacitor C that in miniature reception earphone B, connects in the peripheral cell 5 of radio reception integrated package ₄, the reception tuning capacitor of double as transponder A output signal makes miniature reception earphone B can receive the audio signal of forwarding and the output signal that receives FM radio station.Concerning the FM reception earphone, generally in put under the amplitude limit and listen to, the size of audio frequency output is constant substantially.So, can save volume potentiometer as long as adjust volume in advance.The CT of audio signal transponder is inserted the audio-visual equipment audio output jack that is using, turns on the power switch K11, promptly begin to transmit, open miniature reception earphone mains switch K21 again, just can be in the scope of 10 meters of radiuses uppick audio signal clearly.When transmitting frequency and local checking station with frequency, can stir frequency conversion K switch 12, the K22 of transponder, receiver simultaneously, avoid co-channel interference.

The utility model has following advantage and good effect compared with the prior art:

1, can with high fidelity transmit, receive the audio signal of television set, radio cassette player, radio, phonograph output or use its miniature reception earphone to receive the signal of checking station.

2, adopt the frequency modulation standard, audio band is widened, and antijamming capability is strong, and audio distortion is little.

3, volume is little, and is in light weight, easy to use, reliable, cheap.

Claims

The cover machine is transmitted, received to a kind of miniature Hi-Fi audio signal, comprise the audio signal transponder A that forms by audio signal input circuit 1, modulator 2, oscillator 3, radio frequency output loop 4 and the miniature reception earphone B that forms by radio reception integrated package and peripheral cell 5 thereof, audio frequency output loop 6, pronunciation device 7, send and receive with the frequency modulation standard between transponder A and the miniature reception earphone B, it is characterized in that: the trimmer capacitor C that in transponder A internal oscillator 3, connects ₆, the frequency when making its work just in time is in the operating frequency range of radio reception integrated package in the miniature reception earphone B; The local oscillation tuning capacitor C that in miniature reception earphone B, connects in the peripheral positive part 5 of radio reception integrated package ₄, the reception tuning capacitor of double as transponder A output signal; The frequency conversion K switch that connects on the oscillator 3 in the transponder A ₁₂With the frequency conversion K switch that is connected in the radio reception integrated package peripheral cell 5 in the miniature reception earphone B ₂₂Corresponding, make miniature reception earphone B when receiving forward signal, avoid the output signal of FM radio station.