CN203563033U - Novel frequency modulation circuit - Google Patents
Novel frequency modulation circuit Download PDFInfo
- Publication number
- CN203563033U CN203563033U CN201320723276.3U CN201320723276U CN203563033U CN 203563033 U CN203563033 U CN 203563033U CN 201320723276 U CN201320723276 U CN 201320723276U CN 203563033 U CN203563033 U CN 203563033U
- Authority
- CN
- China
- Prior art keywords
- capacitor
- electric capacity
- resistance
- triode
- resistor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Landscapes
- Transmitters (AREA)
Abstract
The utility model discloses a novel frequency modulation circuit. The novel frequency modulation circuit comprises a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh capacitor, an eighth capacitor, a ninth capacitor, a tenth capacitor, a first inductor, a second inductor, a diode, a first triode and a second triode, a first terminal of the first capacitor is a signal input terminal, a second terminal of the first capacitor is respectively connected with a first terminal of the second capacitor and a first terminal of the first resistor, and a second terminal of the second capacitor is connected to the ground. According to the novel frequency modulation circuit, base electrode bias of an oscillation transistor is changed by the adoption of modulation signals so that the frequency is changed by the change of interelectrode capacitance, the capacity of the fourth capacitor and the fifth capacitor are small, the capacitance of the fourth capacitor and the fifth capacitor is outputted via the second triode, the influence of impedance change on an oscillation circuit is reduced, the interference immunity can be effectively enhanced, and frequency modulation processing for ultrahigh frequency signals can be performed.
Description
Technical field
The utility model relates to a kind of FM circuit, relates in particular to a kind of novel FM circuit.
Background technology
Frequency modulation be exactly the frequency of high frequency carrier be not a constant, it is the modulation system changing within the specific limits with modulation signal, its amplitude is a constant, corresponding with it, amplitude modulation be exactly the frequency of carrier frequency be constant, its amplitude becomes with modulation signal, always general interference signal is superimposed upon on signal, changes its amplitude.Although so frequency-modulated wave also can change in amplitude after being interfered, can the variation in signal amplitude be pruned with amplitude limiter at receiving terminal, traditional FM circuit is lower to hyperfrequency carrier signal fm capacity, after frequency is too high, can make its anti-interference reduce.
Utility model content
The purpose of this utility model provides a kind of novel FM circuit with regard to being in order to address the above problem.
The utility model is achieved through the following technical solutions above-mentioned purpose:
A kind of novel FM circuit, comprise the first resistance to the eight resistance, the first electric capacity to the ten electric capacity, the first inductance, the second inductance, diode, the first triode and the second triode, the first end of described the first electric capacity is signal input part, the second end of described the first electric capacity is connected with the first end of described the first resistance with the first end of described the second electric capacity respectively, the second end ground connection of described the second electric capacity, the second end of described the first resistance respectively with the first end of described the 3rd electric capacity, the first end of described the second resistance, described the 3rd first end of resistance and the base stage of described triode are connected, the second end ground connection of described the 3rd electric capacity, the second end of described the 3rd resistance is connected with the positive pole of described diode, the minus earth of described diode, the emitter of described the first triode respectively with the first end of described the 4th resistance, the first end of described the 4th electric capacity, the first end of described the 5th electric capacity is connected with the first end of described the 5th resistance, the second end ground connection of described the 5th electric capacity, the second end ground connection of described the 4th resistance, the second end ground connection of described the 4th electric capacity, the second end of described the second resistance respectively with the first end of described the tenth electric capacity, the first end of described the second inductance, the first end of described the first inductance is connected with the first end of described the 7th resistance, the second end of described the second inductance is connected with the second end of described the 4th electric capacity with the collector electrode of described the first triode respectively, the second end of described the 5th resistance is connected with the first end of described the 6th electric capacity, the second end of described the 6th electric capacity respectively with the first end of described the 6th resistance, the second end of described the 7th resistance is connected with the base stage of described the second triode, the emitter of described the second triode is connected with the first end of described the 7th electric capacity with the first end of described the 8th resistance respectively, the second end ground connection of described the 8th resistance, the second end ground connection of described the 7th electric capacity, the collector electrode of described the second triode is connected with the first end of described the 9th electric capacity and the second end of described the first inductance respectively, the second end of described the 9th electric capacity is connected with described the 8th electric capacity first end respectively, the second end ground connection of described the 8th electric capacity, the second end of described the 9th electric capacity is signal output part.
The beneficial effects of the utility model are:
Thereby a kind of novel FM circuit of the utility model is the method that adopts modulation signal to change the base bias change interelectrode capacitance of oscillistor changes frequency, the capacity of the 4th electric capacity and the 5th electric capacity is very little, by the second triode, export, reduce the impact of impedance variation on oscillating circuit, use this circuit can effectively strengthen its anti-interference, can carry out frequency modulation processing to ultra-high frequency signal.
Accompanying drawing explanation
Fig. 1 is the circuit diagram of a kind of novel FM circuit of the utility model.
Embodiment
Below in conjunction with accompanying drawing, the utility model is described in further detail:
As shown in Figure 1, a kind of novel FM circuit of the utility model, comprise that the first resistance R 1 is to the 8th resistance R 8, the first capacitor C 1 is to the tenth capacitor C 10, the first inductance L 1, the second inductance L 2, diode D, the first triode T1 and the second triode T2, the first end of the first capacitor C 1 is signal input part, the second end of the first capacitor C 1 is connected with the first end of the first resistance R 1 with the first end of the second capacitor C 2 respectively, the second end ground connection of the second capacitor C 2, the second end of the first resistance R 1 respectively with the first end of the 3rd capacitor C 3, the first end of the second resistance R 2, the 3rd first end of resistance R 3 and the base stage of triode are connected, the second end ground connection of the 3rd capacitor C 3, the second end of the 3rd resistance R 3 is connected with the positive pole of diode D, the minus earth of diode D, the emitter of the first triode T1 respectively with the first end of the 4th resistance R 4, the first end of the 4th capacitor C 4, the first end of the 5th capacitor C 5 is connected with the first end of the 5th resistance R 5, the second end ground connection of the 5th capacitor C 5, the second end ground connection of the 4th resistance R 4, the second end ground connection of the 4th capacitor C 4, the second end of the second resistance R 2 respectively with the first end of the tenth capacitor C 10, the first end of the second inductance L 2, the first end of the first inductance L 1 is connected with the first end of the 7th resistance R 7, the second end of the second inductance L 2 is connected with the second end of the 4th capacitor C 4 with the collector electrode of the first triode T1 respectively, the second end of the 5th resistance R 5 is connected with the first end of the 6th capacitor C 6, the second end of the 6th capacitor C 6 respectively with the first end of the 6th resistance R 6, the second end of the 7th resistance R 7 is connected with the base stage of the second triode T2, the emitter of the second triode T2 is connected with the first end of the 7th capacitor C 7 with the first end of the 8th resistance R 8 respectively, the second end ground connection of the 8th resistance R 8, the second end ground connection of the 7th capacitor C 7, the collector electrode of the second triode T2 is connected with the second end of the first inductance L 1 with the first end of the 9th capacitor C 9 respectively, the second end of the 9th capacitor C 9 is connected with the 8th capacitor C 8 first ends respectively, the second end ground connection of the 8th capacitor C 8, the second end of the 9th capacitor C 9 is signal output part.
The operation principle of a kind of novel FM circuit of the utility model is as follows:
Thereby this circuit is the method that adopts modulation signal to change the base bias change interelectrode capacitance of oscillistor changes frequency, transmitting range is between 50～1OOm, in order to obtain larger frequency shift (FS), the capacity of the 4th capacitor C 4 and the 5th capacitor C 5 should be very little, the inductance value of the first inductance L 1 is that 0.3 μ H left and right is more suitable, because being subject to the impact of first triode T1 utmost point department's electric capacity or parasitic capacitance, should adopt air core coil, and regulate between line tightness to obtain best inductance value, by the second triode T2, export, reduce the impact of impedance variation on oscillating circuit.
Claims (1)
1. a novel FM circuit, it is characterized in that: comprise the first resistance to the eight resistance, the first electric capacity to the ten electric capacity, the first inductance, the second inductance, diode, the first triode and the second triode, the first end of described the first electric capacity is signal input part, the second end of described the first electric capacity is connected with the first end of described the first resistance with the first end of described the second electric capacity respectively, the second end ground connection of described the second electric capacity, the second end of described the first resistance respectively with the first end of described the 3rd electric capacity, the first end of described the second resistance, described the 3rd first end of resistance and the base stage of described triode are connected, the second end ground connection of described the 3rd electric capacity, the second end of described the 3rd resistance is connected with the positive pole of described diode, the minus earth of described diode, the emitter of described the first triode respectively with the first end of described the 4th resistance, the first end of described the 4th electric capacity, the first end of described the 5th electric capacity is connected with the first end of described the 5th resistance, the second end ground connection of described the 5th electric capacity, the second end ground connection of described the 4th resistance, the second end ground connection of described the 4th electric capacity, the second end of described the second resistance respectively with the first end of described the tenth electric capacity, the first end of described the second inductance, the first end of described the first inductance is connected with the first end of described the 7th resistance, the second end of described the second inductance is connected with the second end of described the 4th electric capacity with the collector electrode of described the first triode respectively, the second end of described the 5th resistance is connected with the first end of described the 6th electric capacity, the second end of described the 6th electric capacity respectively with the first end of described the 6th resistance, the second end of described the 7th resistance is connected with the base stage of described the second triode, the emitter of described the second triode is connected with the first end of described the 7th electric capacity with the first end of described the 8th resistance respectively, the second end ground connection of described the 8th resistance, the second end ground connection of described the 7th electric capacity, the collector electrode of described the second triode is connected with the first end of described the 9th electric capacity and the second end of described the first inductance respectively, the second end of described the 9th electric capacity is connected with described the 8th electric capacity first end respectively, the second end ground connection of described the 8th electric capacity, the second end of described the 9th electric capacity is signal output part.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320723276.3U CN203563033U (en) | 2013-11-15 | 2013-11-15 | Novel frequency modulation circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320723276.3U CN203563033U (en) | 2013-11-15 | 2013-11-15 | Novel frequency modulation circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203563033U true CN203563033U (en) | 2014-04-23 |
Family
ID=50512728
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201320723276.3U Expired - Fee Related CN203563033U (en) | 2013-11-15 | 2013-11-15 | Novel frequency modulation circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN203563033U (en) |
-
2013
- 2013-11-15 CN CN201320723276.3U patent/CN203563033U/en not_active Expired - Fee Related
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN201903573U (en) | Current detection and amplification circuit used for two-wire manufactured instrument | |
| CN203563033U (en) | Novel frequency modulation circuit | |
| CN203180902U (en) | A frequency modulation transmitter with strong anti-interference performance | |
| CN202364117U (en) | Internal power supply circuit of concentrator | |
| CN204206115U (en) | A kind of amplifying circuit for wireless short wave transmitting antenna | |
| CN104639102A (en) | Novel frequency modulation circuit | |
| CN204206394U (en) | A kind of wireless microphone of reliable operation | |
| CN204810142U (en) | High frequency switching power supply's anti -jamming circuit | |
| CN104702297A (en) | Radio audio amplitude modulation transmitter | |
| CN104702295A (en) | Remote low-power radio frequency-modulated transmitter | |
| CN203181056U (en) | Novel anti-interference modem | |
| CN103532572A (en) | Low-power high-sensitivity FM transmitter | |
| CN203166882U (en) | Novel long-distance transmitter | |
| CN204556097U (en) | A kind of reactor vibration wireless alarming emissioning circuit | |
| CN104065392A (en) | Frequency modulation transmitter with high interference resistance | |
| CN204244181U (en) | The amplifying circuit of analog signal of radiofrequency signal | |
| CN203193616U (en) | Low-power high-sensitivity frequency band transmitter | |
| CN104660275A (en) | Short wave amplitude modulated transmitter circuit | |
| CN202043264U (en) | Frequency modulation wireless microphone circuit with voltage stabilizing circuit | |
| CN204206431U (en) | A kind of wireless microphone circuit | |
| CN104702296A (en) | Wireless frequency modulation transmission circuit | |
| CN203504549U (en) | Receiver used for aeronautical communication station | |
| CN203225738U (en) | Small-power high-frequency transmitting circuit used for acoustic wave transmitter | |
| CN204906322U (en) | Power consumptive few high frequency amplifier | |
| CN104636787A (en) | Demodulating circuit for ultrahigh-frequency RFID (radio frequency identification) tag chip |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20140423 Termination date: 20141115 |
|
| EXPY | Termination of patent right or utility model |