CN204392182U

CN204392182U - Non-transformer micropower frequency modulation transponder

Info

Publication number: CN204392182U
Application number: CN201520155036.7U
Authority: CN
Inventors: 王志
Original assignee: Individual
Current assignee: Individual
Priority date: 2015-03-18
Filing date: 2015-03-18
Publication date: 2015-06-10
Anticipated expiration: 2025-03-18

Abstract

The utility model is about a kind of non-transformer micropower frequency modulation transponder, its feature comprises: audio signal interface and voltage doubling rectifing circuit, pi filter and voltage stabilizing circuit, the bikini higher-order of oscillation and frequency-modulated wave radiating circuit, the model that in circuit, NPN transistor VT1 selects is power transistor in 2SC9018.The utility model does not need, by powered battery, audio signal to be forwarded on 88 ~ 108MHz fm band, can use FM broadcast receiver to receive.The utility model only uses a NPN transistor because of circuit, therefore involving and disturbing few by front stage, make frequency of oscillation more stable, transmitting range can reach 8m.The utility model can listen to television field frame with FM broadcast receiver, by television field frame audio signal convert wireless signals, can realize the wireless listening function of television field frame earphone; The programs such as available recordings machine antenna wireless record tv sound accompaniment.The utility model have circuit structure simple, be easy to features such as debuging.

Description

Non-transformer micropower frequency modulation transponder

Technical field

The utility model belongs to wireless communication technique field, is about a kind of non-transformer micropower frequency modulation transponder.

Background technology

The typical operation principle of most frequency modulation wireless microphones is the modulating frequency being changed high-frequency generator by the junction capacitance change changed in high-frequency oscillating circuits between transistor collector and emitter, thus realize becoming frequency-modulated wave to frequency of oscillation modulation, amplified by high frequency selective frequency amplifier circuit, finally by transmitting antenna to space radiation.

Non-transformer micropower frequency modulation transponder described in the utility model does not need, by powered battery, audio signal to be forwarded on 88 ~ 108MHz fm band, can use FM broadcast receiver to receive.The utility model only uses a NPN transistor because of circuit, therefore involving and disturbing few by front stage, make frequency of oscillation more stable, transmitting range can reach 8m.

The utility model can listen to television field frame with FM broadcast receiver, by television field frame audio signal convert wireless signals, can realize the wireless listening function of television field frame earphone; The programs such as available recordings machine antenna wireless record tv sound accompaniment.The utility model have circuit structure simple, be easy to features such as debuging.

Below describe in detail non-transformer micropower frequency modulation transponder described in the utility model necessity involved in implementation process, guardian technique content.

Utility model content

Goal of the invention and beneficial effect: non-transformer micropower frequency modulation transponder described in the utility model does not need, by powered battery, audio signal to be forwarded on 88 ~ 108MHz fm band, can use FM broadcast receiver to receive.The utility model only uses a NPN transistor because of circuit, therefore involving and disturbing few by front stage, make frequency of oscillation more stable, transmitting range can reach 8m.The utility model can listen to television field frame with FM broadcast receiver, by television field frame audio signal convert wireless signals, can realize the wireless listening function of television field frame earphone; The programs such as available recordings machine antenna wireless record tv sound accompaniment.The utility model have circuit structure simple, be easy to features such as debuging.

Circuit working principle: the circuit of non-transformer micropower frequency modulation transponder is by audio signal interface IN input audio signal, audio signal voltage is through electric capacity C4, after germanium diode D1 and germanium diode D2 voltage multiplying rectifier, by electric capacity C3, resistance R1 and electrochemical capacitor C2 forms pi filter filtering, again after voltage stabilizing didoe DW voltage stabilizing, obtain the work of about 1.5V direct voltage supply circuit, bikini high-frequency oscillating circuits is by NPN transistor VT1, higher-order of oscillation coil L1, variable capacitance CP forms, the base stage of NPN transistor VT1 is simultaneously by the control of audio signal, thus frequency of oscillation is modulated to frequency-modulated wave, frequency-modulated wave is radiate by transmitting antenna ANT (with 0.8m multiply plastics cord).

Technical scheme: non-transformer micropower frequency modulation transponder, it comprises audio signal interface and voltage doubling rectifing circuit, pi filter and voltage stabilizing circuit, the bikini higher-order of oscillation and frequency-modulated wave radiating circuit, it is characterized in that:

Audio interface and voltage doubling rectifing circuit: it is made up of audio interface IN, linear potentiometer RP, electric capacity C4, germanium diode D1 and germanium diode D2, the emitter of upper termination NPN transistor VT1 of audio signal interface IN and one end of linear potentiometer RP, the lower other end of terminated line potentiometer RP of audio signal interface IN and one end of electric capacity C4, the negative pole of another termination germanium diode D1 of electric capacity C4 and the positive pole of germanium diode D2;

Pi filter and voltage stabilizing circuit: it is made up of electric capacity C3, resistance R1, electrochemical capacitor C2 and voltage stabilizing didoe DW, the positive pole of germanium diode D1 connects the negative pole of one end of electric capacity C3 and the positive pole of electrochemical capacitor C2 and voltage stabilizing didoe DW, the negative pole of germanium diode D2 connects the other end of electric capacity C3 and one end of resistance R1, the negative pole of another termination electrochemical capacitor C2 of resistance R1 and the positive pole of voltage stabilizing didoe DW and circuit ground GND;

The bikini higher-order of oscillation and frequency-modulated wave radiating circuit: it is by NPN transistor VT1, higher-order of oscillation coil L1, variable capacitance CP and coupling capacitance C1 and transmitting antenna ANT forms, the model that NPN transistor VT1 selects is power transistor in 2SC9018, the base stage of NPN transistor VT1, the one termination circuit ground GND of the movable end of linear potentiometer RP and one end of variable capacitance CP and higher-order of oscillation coil L1, the collector electrode of NPN transistor VT1 connects the other end of variable capacitance CP and the other end of higher-order of oscillation coil L1, the collector electrode of NPN transistor VT1 meets transmitting antenna ANT by coupling capacitance C1.

Accompanying drawing explanation

Accompanying drawing 1 is the circuit working schematic diagram of the non-transformer micropower frequency modulation transponder embodiment that the utility model provides.

Embodiment

According to the non-transformer micropower frequency modulation repeater circuit fundamental diagram shown in accompanying drawing 1 and accompanying drawing explanation, and according to annexation between components and parts in each several part circuit described in utility model content, and components and parts technical parameter described in execution mode requires and circuit production main points are carried out enforcement and can be realized the utility model, is further described correlation technique of the present utility model below in conjunction with embodiment.

The technical parameter of components and parts and selection requirement thereof

VT1 is NPN transistor, and require that the characteristic frequency fT of transistor is greater than 300MHz, the model selected is power transistor in 2SC9018, requires β >=110;

D1, D2 are germanium diode, and the model selected is 2AP9; DW is voltage stabilizing didoe, and parameter is 1.5V;

RP is linear potentiometer, and the resistance of use is 1K Ω; The resistance of resistance R1 is 1K Ω;

CP is tunable capacitor, and its range of capacity is 4 ~ 25PF;

C1 is ceramic disc capacitor, and capacity is 15PF; C2 is electrochemical capacitor, and capacity is 10 μ F/10V; C3 is ceramic disc capacitor, and capacity is 4700PF; C4 is ceramic disc capacitor, and capacity is 0.22 μ F.

Circuit production main points and circuit debugging

Higher-order of oscillation coil L makes: the enamelled wire using ￠ 0.5mm, flat around 10 circles on the ballpoint pen core of ￠ 3.5mm, then extract pen core out and form air-core inductance, scrapes off coil two ends coat of paint zinc-plated;

ANT is the telescopic antenna of transmitting antenna, available more than 60cm, and 80cm multiply plastics cord also can be used as transmitting antenna, and on a printed circuit, the other end of transmitting antenna ANT naturally droops in one end weldering;

Require that each component's feet should stay shorter as far as possible, first check printed circuit board (PCB) and element welding situation, should, without short circuit and false weldering phenomenon, when noting welding, higher-order of oscillation coil L1 can not be made to be out of shape; Then amplitude >=0.5V audio signal is accessed at audio signal interface IN, universal instrument shelves of direct voltage to measure between the base stage of NPN transistor VT1 and emitter voltage should > 0.7V, by higher-order of oscillation coil L1 two terminal shortcircuit once, its voltage should change to some extent, and circuit starting of oscillation is described;

Turn on FM broadcast receiver, the wireless antenna of pull-out FM, by transmitting antenna ANT near FM broadcast receiver; Then slowly rotate FM radio tuner knob, adjust variable capacitance CP simultaneously, be tuned to till FM broadcast receiver receives voice signal sound.If FM broadcast receiver can not receive frequency-modulated wave and transmits in tuning range, can stretch or compress higher-order of oscillation coil L1 gently, change the width of higher-order of oscillation coil L1, more careful tuning FM broadcast receiver receive frequency, until receive voice signal;

Pull open the distance between non-transformer micropower frequency modulation transponder and FM broadcast receiver, until when distance reaches 8m, till still can receiving voice signal, and then adjust linear potentiometer RP to make sound clarity.

Circuit components layout of the present utility model, circuit structure design, its shape and size etc. of outward appearance are not all key technologies of the present utility model; neither the claimed technology contents of the utility model; because not affecting the utility model specific implementation process, therefore do not illustrate one by one in the description.

Claims

1. a non-transformer micropower frequency modulation transponder, it comprises audio signal interface and voltage doubling rectifing circuit, pi filter and voltage stabilizing circuit, the bikini higher-order of oscillation and frequency-modulated wave radiating circuit, it is characterized in that:

Described audio signal interface and voltage doubling rectifing circuit are made up of audio interface IN, linear potentiometer RP, electric capacity C4, germanium diode D1 and germanium diode D2, the emitter of upper termination NPN transistor VT1 of audio signal interface IN and one end of linear potentiometer RP, the lower other end of terminated line potentiometer RP of audio signal interface IN and one end of electric capacity C4, the negative pole of another termination germanium diode D1 of electric capacity C4 and the positive pole of germanium diode D2;

Described pi filter and voltage stabilizing circuit are made up of electric capacity C3, resistance R1, electrochemical capacitor C2 and voltage stabilizing didoe DW, the positive pole of germanium diode D1 connects the negative pole of one end of electric capacity C3 and the positive pole of electrochemical capacitor C2 and voltage stabilizing didoe DW, the negative pole of germanium diode D2 connects the other end of electric capacity C3 and one end of resistance R1, the negative pole of another termination electrochemical capacitor C2 of resistance R1 and the positive pole of voltage stabilizing didoe DW and circuit ground GND;

The described bikini higher-order of oscillation and frequency-modulated wave radiating circuit are by NPN transistor VT1, higher-order of oscillation coil L1, variable capacitance CP and coupling capacitance C1 and transmitting antenna ANT forms, the model that NPN transistor VT1 selects is power transistor in 2SC9018, the base stage of NPN transistor VT1, the one termination circuit ground GND of the movable end of linear potentiometer RP and one end of variable capacitance CP and higher-order of oscillation coil L1, the collector electrode of NPN transistor VT1 connects the other end of variable capacitance CP and the other end of higher-order of oscillation coil L1, the collector electrode of NPN transistor VT1 meets transmitting antenna ANT by coupling capacitance C1.