CN105101012B - Short distance 3.5MHz channels watchers - Google Patents
Short distance 3.5MHz channels watchers Download PDFInfo
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- CN105101012B CN105101012B CN201510345146.4A CN201510345146A CN105101012B CN 105101012 B CN105101012 B CN 105101012B CN 201510345146 A CN201510345146 A CN 201510345146A CN 105101012 B CN105101012 B CN 105101012B
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Abstract
The present invention relates to a kind of short distance 3.5MHz channels watchers, control circuit including shell and in shell, control circuit includes direction-finder antenna, high-frequency amplifying unit, adjustable signal generator based on heter rodyne action, difference frequency detection unit and audio amplification unit, direction-finder antenna is connected with the input terminal of high-frequency amplifying unit, the output end of the output end of high-frequency amplifying unit and adjustable signal generator based on heter rodyne action is connected with the input terminal of difference frequency detection unit respectively, the output end of difference frequency detection unit is connected with the input terminal of audio amplification unit, and the output end of audio amplification unit is connected with earphone interface.The present invention is only with an adjustable signal generator based on heter rodyne action, directly it is poor go out low frequency signal, play the role of channel selection and beat simultaneously, intermediate frequency conversion and processing circuit is omitted, circuit is simple, using flexible, radio reception capability is strong, it is suitble to compete under the particular surroundings such as mountainous region and uses, use scope is wide, meets the needs of direction-finding station campaign under various environment.
Description
Technical field
The present invention relates to a kind of channels watcher more particularly to a kind of short distance 3.5MHz channels watchers.
Background technology
Direction-finding station campaign grows up on the basis of radio amateur carries out amateur communication extensively.Wirelessly
Electrical measurement is very interesting to contest, just as playing the game of hide and seek, sportsman busily audiometry, run, go search one all over the mountains and plains
Each and every one hidden radio station.Direction-finding station contest is again very mysterious, and contest region secrecy, station location secrecy, sportsman is in contest
Think independently in the process and move, cannot get the guidance of coach, mustn't also receive anyone any help and prompt, only
Channels watcher is the loyal partner of sportsman, and player hand takes channels watcher, wears the earphone search being attached thereto
The radio station hidden one by one set in advance to contest organizer.
It is 80 VHF band short-range radio radio direction findings wherein to popularize most commonly used.80 current VHF band short distances
Channels watcher generally uses superhet direction-finder set, and there are two oscillators：One is the machine oscillator, is generated than outer
The high-frequency oscillation signal of the high or low 465KHz of signal is received, after being mixed with high discharge signal, obtains the intermediate frequency letter of a 465KHz
Number, then carry out IF process；The other is signal generator based on heter rodyne action, generates the oscillation letter of 1KHz more high or low than 465KHz intermediate-freuqncy signal
Number, the low frequency signal that output signal difference goes out 1KHz is put in.Not only circuit structure is complicated for this channels watcher, cost compared with
Height, and radio reception capability is than relatively limited.If certain in 2013 is competed, since competition area are located at mountainous region, Er Qie electricity
Air line distance has reached 350 meters or more between platform, and since channels watcher reception ability used is inadequate, playing area just has occurred
Domain is searched the phenomenon that not detecting radio station, and many sportsmen abandon match because can't hear radio station, also have componental movement person to search
It surveys on a large amount of physical efficiencys are put into and cross over mountain after mountain by radio station, affects competition effect, also bring certain danger.
Invention content
Present invention mainly solves original channels watcher circuit structure complexity, and radio reception capability is than relatively limited, no
It is suitble to compete under the particular surroundings such as mountainous region and uses, use scope is than more limited technical problem；A kind of short distance is provided
3.5MHz channels watchers, circuit is simple, and radio reception capability is stronger, and being suitble to compete under the particular surroundings such as mountainous region makes
With use scope is wide, meets the needs of direction-finding station campaign under various environment.
The above-mentioned technical problem of the present invention is mainly to be addressed by following technical proposals：The present invention include shell and
Control circuit in shell, control circuit include direction-finder antenna, high-frequency amplifying unit, adjustable signal generator based on heter rodyne action, difference frequency inspection
The input terminal of wave unit and audio amplification unit, direction-finder antenna and high-frequency amplifying unit is connected, the output end of high-frequency amplifying unit
And the output end of adjustable signal generator based on heter rodyne action is connected with the input terminal of difference frequency detection unit respectively, the output end of difference frequency detection unit and
The input terminal of audio amplification unit is connected, and the output end of audio amplification unit is connected with earphone interface.Direction-finder antenna receives electricity
After the able one signal for 3.5~3.6MHz that platform is sent out, send to high-frequency amplifying unit and be amplified, amplified signal with can
The second harmonic of the oscillator signal of 1.75~1.8MHz of signal generator based on heter rodyne action generation is adjusted to be added to difference frequency detection unit together, adjustment is poor
The frequency for clapping oscillator makes it generate the signal more high or low 1KHz than receiving signal, the output of this signal and high-frequency amplifying unit
Signal carries out difference frequency detection, obtains the low frequency signal of 1KHz, then send to audio amplification unit and be amplified again, finally by ear
Machine interface gives earphone, and sportsman can listen to the telegraphic signal sent out to radio station.The present invention is only with an oscillator, you can
Adjust signal generator based on heter rodyne action, directly it is poor go out low frequency signal, while playing the role of channel selection and beat, without this vibration level and in put grade, province
Intermediate frequency conversion and processing circuit are omited, circuit is simple, and using flexible, radio reception capability is stronger, and it is special in mountainous region etc. to be suitble to
It competes and uses under environment, use scope is wide, meets the needs of direction-finding station campaign under various environment.
Preferably, the audio amplification unit includes audio pre-amplifier unit and Audio power amplifier unit, sound
The input terminal of frequency pre-amplifier unit is connected with the output end of the difference frequency detection unit, the output of audio pre-amplifier unit
End is connected with the input terminal of the Audio power amplifier unit, and the output end of Audio power amplifier unit and the earphone connect
Mouth is connected.When direction-finder set farther out from radio station when, the output signal of difference frequency detection unit can be very weak, therefore is put before first passing through audio
Big unit carries out low frequency amplification, then carries out power amplification by Audio power amplifier unit, effectively enhances signal, it is ensured that sportsman
The telegraphic signal heard from earphone is than more visible.
Preferably, the adjustable signal generator based on heter rodyne action includes beat oscillator coil B2, triode T3, varactor
D2, adjustable resistance RP3 and voltage-stabiliser tube D3, the collector of triode T3 and the cathode of voltage-stabiliser tube D3, one of adjustable resistance RP3 it is solid
Fixed end is connected and connects the ends voltage V1, and another fixing end of adjustable resistance RP3 connects the ends voltage V2, voltage-stabiliser tube through resistance R14
The anode of D3 also connects the ends voltage V2, and the emitter of triode T3 connects the ends voltage V2 through the parallel circuit of resistance R12 and capacitance C18,
Capacitance C17 and voltage-stabiliser tube D3 are in parallel, and the movable end of adjustable resistance RP3 is connected with one end of capacitance C20 and resistance R13, capacitance C20
The other end be connected with the cathode of voltage-stabiliser tube D3, the other end of resistance R13 is connected with the cathode of varactor D2, two pole of transfiguration
The anode of pipe D2 connects the ends voltage V2, and one end of resistance R10 is connected with the collector of triode T3, one end of capacitance C16 and three poles
The emitter of pipe T3 is connected, and the other end of resistance R10 and capacitance C16 are connected with one end of resistance R11, and resistance R11's is another
The base stage at the ends termination voltage V2, triode T3 is connected with one end of the primary coil of beat oscillator coil B2, beat oscillator coil
The other end of the primary coil of B2 had not only connect the ends voltage V2 through capacitance C14 but also had been connected with the cathode of varactor D2 through capacitance C15,
One end of the secondary wire coil of beat oscillator coil B2 is connected with the input terminal of the difference frequency detection unit, beat oscillator coil B2
Secondary wire coil the ends another termination voltage V2.The adjustable signal generator based on heter rodyne action of the technical program is that tandem type capacitance three-point type shakes
Swing circuit.Using electric tuning mode, by adjusting adjustable resistance RP3, changes the bias voltage being added on varactor D2 and come
The capacitance for changing the both ends varactor D2 achievees the purpose that adjust platform to change frequency of oscillation.Adjustable resistance RP3, resistance
The biasing circuit of R13 and resistance R14 composition varactors D2.To obtain wider frequency range, optional electricity capacity
Change big varactor, the resistance value of resistance R13, resistance R14 also can be changed.Capacitance C14, capacitance C15 are loop resonance electricity
Hold, to improve the frequency stability of circuit, the smaller capacitance of temperature coefficient may be selected in capacitance C14, capacitance C15.Voltage-stabiliser tube D3 rises
To the effect of stabilized oscillator operating voltage.
Preferably, the difference frequency detection unit includes detection tube D1, is made of capacitance C5, capacitance C6 and resistance R5
The anode of filter circuit and detection load resistance R6, detection tube D1 are connected with the output end of the high-frequency amplifying unit, detection
The cathode of pipe D1 was not only connected through capacitance C5 ground connection but also with one end of resistance R5, and the other end of resistance R5 both amplified with the audio
The input terminal of unit is connected to be grounded through capacitance C6 again, and detection load resistance R6 and capacitance C6 are in parallel.Detection tube D1, which is one, to be had
The nonlinear device of unilateral conduction can make the signal of two different frequencies produce many new frequency contents using it.Example
Such as, in addition to original two frequencies, also the sum of two frequencies, the difference etc. of two frequencies.Only it is through high frequency there are one frequency content
The difference (about 1KHz) of the second harmonic of the amplified extraneous signal frequency of amplifying unit and signal generator based on heter rodyne action frequency.Capacitance C5, electricity
Hold C6 and resistance R5 and constitute RC type filter circuits, RC type filter circuits are for filtering out the radio-frequency component after detection, so as in detection
Low-frequency voltage is obtained on load resistance R6.
Preferably, the high-frequency amplifying unit includes triode T1, high unwrapping wire circle B1 and adjustable resistance RP1, three poles
The base stage of pipe T1 is connected through capacitance C2 with the output end of the direction-finder antenna all the way, and another way is grounded through resistance R2, and also one
Road is connected through resistance R1 with the movable end of adjustable resistance RP1, the fixing end ground connection of adjustable resistance RP1, adjustable resistance RP1's
Another fixing end is connected with the ends voltage V1, and the emitter of triode T1 is grounded through the parallel circuit of capacitance C4 and resistance R3, and three
The collector of pole pipe T1 is connected with one end of the primary coil of high unwrapping wire circle B1, and the primary coil of capacitance C3 and high unwrapping wire circle B1 are simultaneously
Connection, the middle tap of the primary coil of high unwrapping wire circle B1 be not only connected with the ends voltage V1 through resistance R4 but also be grounded through capacitance C19, high unwrapping wire
The secondary coil of circle B1 is connected with the input terminal of the difference frequency detection unit.Resistance R1~resistance R4 is biasing resistor, capacitance
C2 is coupled capacitor, and capacitance C3 is resonant capacitance, and capacitance C4 is shunt capacitance.Adjust the magnetic core of high unwrapping wire circle Bl, resonance in
3.57MHz, can be carried out with the resonant frequency 3.53MHz of direction-finder antenna it is staggered tuning, make entire High frequency amplification curve 3.5~
Shallower within the scope of the receives frequency of 3.6MHz, i.e., high amplification gain is more uniform.To make channels watcher believe by force in close-table area
Number when height put grade and choking phenomenon do not occur, remain to maintain normally to amplify and keep good directionality, by adjusting adjustable electric
Resistance RP1 can control height to put level work point, achieve the purpose that the high amplification gain of control.Attenuator switch is not only omitted in the method, but also
It can get very wide gain control range.
Preferably, the audio pre-amplifier unit includes triode T2, the Audio power amplifier unit packet
Adjustable resistance RP2 and amplifier U are included, the base stage of triode T2 was both connected through capacitance C8 with the output end of the difference frequency detection unit
It is connected again with the collector of triode T2 through resistance R8, the emitter ground connection of triode T2, the collector of triode T2 is both through electricity
Resistance R9 is connected with the ends voltage V1 and is connected with the anode of electrolytic capacitor C10, and the cathode of electrolytic capacitor C10 was both grounded through capacitance C11
It is connected again with a fixing end of adjustable resistance RP2, another fixing end ground connection of adjustable resistance RP2, the work of adjustable resistance RP2
Moved end is connected with the inverting input of amplifier U, and the in-phase input end ground connection of amplifier U, the ends voltage V1 are connected with one end of resistance R7,
The other end of resistance R7 not only with the anode of battery BT was connected through electrolytic capacitor C9 ground connection but also through switch K, the output end and electricity of amplifier U
The anode for solving capacitance C13 is connected, and the cathode of electrolytic capacitor C13 is connected with the anode of earphone socket CK, the cathode of earphone socket CK
It is grounded, feedback capacity C12, adjustable resistance RP2 and adjustable resistance RP1 is also associated on amplifier U using the duplex electricity coaxially controlled
Position device.Triode T2, resistance R8, resistance R9 and capacitance C8, the total emitting stage amplifier of electrolytic capacitor C10 compositions, wherein resistance R8,
Resistance R9 is negative voltage feedback biasing circuit, and capacitance C8, electrolytic capacitor C10 are coupling capacitor.When channels watcher is from electricity
Platform farther out when, difference frequency detection unit output audio signal will be very weak, the technical program first carries out it with low frequency triode T2
Primary amplification, then total emitting stage amplification is carried out, enhance signal, it is ensured that sportsman can clearly recognize.The preposition amplification of audio
Signal afterwards is bonded to amplifier U through electrolytic capacitor C10 lotus roots and carries out power amplification.When feedback capacity C12 is 10 μ F, the electricity of amplifier U
Press gain up to 100 times.Adjustable resistance RP2 is adjusted, the volume of the audio signal of output can be changed.Capacitance C11 is high frequency
Shunt capacitance, make in audio signal the higher partial short circuit of frequency enter without being amplified, to weaken ear-piercing in earphone " neigh
Neigh " ambient noise.Electrolytic capacitor C13 is output coupling capacitor, the adjustable resistance in adjustable resistance RP2 and high-frequency amplifying unit
RP1 is coaxially controlled.
Preferably, the direction-finder antenna includes upright antenna, single-direction and dual-direction change-over switch S and the magnetic day being mutually coupled
Line L1 and magnetic antenna L2, upright antenna are connected with the public foot of single-direction and dual-direction change-over switch S, one of single-direction and dual-direction change-over switch S
Haptic element is grounded through the series circuit of phase modulation resistance R15 and tuning capacitance C1, and magnetic antenna L1 and tuning capacitance C1 are in parallel, single-direction and dual-direction
Another haptic element of change-over switch S and one end of magnetic antenna L2 are grounded, the other end of magnetic antenna L2 and the high frequency
The input terminal of amplifying unit is connected.Tuning capacitance C1 is adjusted, makes antenna loop resonance in 3.53MHz.It carries out surveying big sound face
When, single-direction and dual-direction change-over switch S is controlled, so that upright antenna is connected with magnetic antenna L1, upright antenna received signal passes through
Magnetic antenna L1 is coupled to magnetic antenna L2, then is conveyed to high-frequency amplifying unit.When the big sound face of accident, magnetic day need not be accessed
Line L1 controls single-direction and dual-direction change-over switch S, upright antenna is made directly to be connected with magnetic antenna L2, and upright antenna received signal is logical
It crosses magnetic antenna L2 and is conveyed to high-frequency amplifying unit again.Using flexible.
Preferably, the shell be in cuboid, the upright antenna be set to shell top surface, the left side of shell,
Respectively there are one the protective cover for the cylindrical shape for protruding, protruding to the right to the left, two protective covers are described close to the top of shell on right side
Magnetic antenna L1 and magnetic antenna L2 be located at the protective cover in left side, right side protective cover in, the left side of shell, which is equipped with, adjusts
Platform knob and volume adjustment knob, the single-direction and dual-direction change-over switch S use push switch, push switch to be located at shell
Right side, the earphone interface use the earphone interface with power switch, earphone interface to be located at the right side of shell.High frequency amplification
The adjustable resistance RP2 in adjustable resistance RP1 and Audio power amplifier unit in unit is coaxially controlled, and constitutes volume adjustment rotation
Button；Adjustable resistance RP3 in adjustable signal generator based on heter rodyne action constitutes table adjusting knob.Protective cover is to magnetic antenna L1 and magnetic antenna L2
It plays a protective role, can only be damaged to protective cover when colliding with because of transport, vibrations or accidentally, magnetic day will not be damaged to
Line.
The beneficial effects of the invention are as follows：Only use an adjustable signal generator based on heter rodyne action, it is direct it is poor go out low frequency signal, while playing choosing
Platform and beat effect, are omitted intermediate frequency conversion and processing circuit, and circuit is simple, and using flexible, radio reception capability is strong, is suitble to
It competes and uses under the particular surroundings such as mountainous region, use scope is wide, meets the needs of direction-finding station campaign under various environment.
Description of the drawings
Fig. 1 is a kind of main structure diagram of the present invention.
Fig. 2 is a kind of circuit theory connection block diagram of the present invention.
Fig. 3 is a kind of circuit diagram of the present invention.
1. shell in figure, 2. direction-finder antennas, 3. high-frequency amplifying units, 4. adjustable signal generator based on heter rodyne actions, 5. difference frequency detection units,
6. audio amplification unit, 7. earphone interfaces, 8. audio pre-amplifier units, 9. Audio power amplifier units, 10. protective covers, 11.
Table adjusting knob, 12. volume adjustment knobs, 13. push switch, 21. upright antennas.
Specific implementation mode
Below with reference to the embodiments and with reference to the accompanying drawing the technical solutions of the present invention will be further described.
Embodiment：The short distance 3.5MHz channels watchers of the present embodiment, including shell 1 and in shell 1
Control circuit.As shown in Figure 1, shell 1 is in cuboid, the top surface of shell 1 is equipped with upright antenna 21, left side, the right side of shell 1
Each there are one the protective covers 10 for the cylindrical shape for protruding, protruding to the right to the left, and two protective covers 10 are close to the top of shell 1, a left side
Magnetic antenna L1 and magnetic antenna L2 is separately installed in the protective cover of side, the protective cover on right side, the left side of shell 1 is also equipped with
One table adjusting knob 11 and a volume adjustment knob 12, there are one push switch 13 and a bands for the right side installation of shell 1
There is the earphone interface 7 of power switch.As shown in Fig. 2, control circuit includes direction-finder antenna 2, high-frequency amplifying unit 3, adjustable beat
Oscillator 4, difference frequency detection unit 5 and the audio amplification list being made of audio pre-amplifier unit 8 and Audio power amplifier unit 9
Member 6, direction-finder antenna 2 is connected with the input terminal of high-frequency amplifying unit 3, the output end of high-frequency amplifying unit 3 and adjustable beat oscillation
The output end of device 4 is connected with the input terminal of difference frequency detection unit 5 respectively, is put before the output end and audio of difference frequency detection unit 5
The input terminal of big unit 8 is connected, and the output end of audio pre-amplifier unit 8 is connected with the input terminal of Audio power amplifier unit 9,
The output end of Audio power amplifier unit 9 is connected with earphone interface 7.
As shown in figure 3, entire control circuit is powered by 6V batteries BT, switch K is power switch, earphone socket CK and switch
K is realized by the earphone interface 7 with power switch in Fig. 1.Direction-finder antenna 2 includes upright antenna 21, single-direction and dual-direction change-over switch
S, phase modulation resistance R15, tuning capacitance C1 and the magnetic antenna L1 and magnetic antenna L2 that are mutually coupled, single-direction and dual-direction change-over switch S is just
It is the push switch 13 in Fig. 1；High-frequency amplifying unit 3 includes triode T1, high unwrapping wire circle B1, adjustable resistance RP1, resistance R1
~resistance R4, capacitance C2~capacitance C4 and capacitance C19；Adjustable signal generator based on heter rodyne action 4 include beat oscillator coil B2, triode T3,
Varactor D2, adjustable resistance RP3, voltage-stabiliser tube D3, resistance R10~resistance R14, capacitance C14~capacitance C18 and capacitance C20；
Difference frequency detection unit 5 includes detection tube D1, by capacitance C5, capacitance C6 and resistance the R5 filter circuit constituted and detection load resistance
R6；Audio pre-amplifier unit 8 includes triode T2, resistance R8, resistance R9, capacitance C8 and electrolytic capacitor C10；Audio power is put
Big unit 9 includes adjustable resistance RP2, amplifier U, resistance R7, capacitance C11, electrolytic capacitor C7, electrolytic capacitor C9, electrolytic capacitor C13
With feedback capacity C12.
Upright antenna 21 is connected with 2 feet (public foot) of single-direction and dual-direction change-over switch S, and 1 foot of single-direction and dual-direction change-over switch S is through adjusting
The series circuit of phase resistance R15 and tuning capacitance C1 are grounded, and magnetic antenna L1 and tuning capacitance C1 are in parallel, single-direction and dual-direction change-over switch
3 feet of S and one end of magnetic antenna L2 are grounded, and the other end of magnetic antenna L2 is connected with one end of capacitance C2, capacitance C2's
The other end is connected with the base stage of triode T1, the base stage of triode T1, is grounded all the way through resistance R2, also all the way through resistance R1 and
The movable end of adjustable resistance RP1 is connected, the fixing end ground connection of adjustable resistance RP1, another fixing end of adjustable resistance RP1
It is connected with the ends voltage V1, the emitter of triode T1 is grounded through the parallel circuit of capacitance C4 and resistance R3, the current collection of triode T1
Pole is connected with one end of the primary coil of high unwrapping wire circle B1, the parallel connection of primary windings of capacitance C3 and high unwrapping wire circle B1, high unwrapping wire circle
The middle tap of the primary coil of B1 had not only been connected with the ends voltage V1 through resistance R4 but also had been grounded through capacitance C19, the secondary of high unwrapping wire circle B1
One end of coil is connected with the anode of detection tube D1, the other end of the secondary coil of high unwrapping wire circle B1 and beat oscillator coil B2's
One end of secondary wire coil is connected, the ends another termination voltage V2 of the secondary wire coil of beat oscillator coil B2.Adjustable signal generator based on heter rodyne action
In, the collector of triode T3 is connected with a fixing end of the cathode of voltage-stabiliser tube D3, adjustable resistance RP3 and connects voltage V1
End, another fixing end of adjustable resistance RP3 connect the ends voltage V2 through resistance R14, and the anode of voltage-stabiliser tube D3 also connects the ends voltage V2, and three
Parallel circuit of the emitter of pole pipe T3 through resistance R12 and capacitance C18 connects the ends voltage V2, and capacitance C17 and voltage-stabiliser tube D3 are in parallel, can
The movable end of resistance RP3 is adjusted to be connected with one end of capacitance C20 and resistance R13, the cathode of the other end and voltage-stabiliser tube D3 of capacitance C20
It is connected, the other end of resistance R13 is connected with the cathode of varactor D2, and the anode of varactor D2 connects the ends voltage V2, can
It is exactly the table adjusting knob 11 in Fig. 1 to adjust resistance RP3, and one end of resistance R10 is connected with the collector of triode T3, capacitance C16's
One end is connected with the emitter of triode T3, and the other end of resistance R10 and capacitance C16 are connected with one end of resistance R11, resistance
The base stage at the ends another termination voltage V2 of R11, triode T3 is connected with one end of the primary coil of beat oscillator coil B2, beat
The other end of the primary coil of oscillator coil B2 had not only connect the ends voltage V2 through capacitance C14 but also through capacitance C15's and varactor D2
Cathode is connected.The cathode of detection tube D1 was not only connected through capacitance C5 ground connection but also with one end of resistance R5, and the other end of resistance R5 both passed through
Capacitance C8 is connected with the base stage of triode T2 and is grounded through capacitance C6, and detection load resistance R6 and capacitance C6 are in parallel.Triode T2
Base stage be connected with the collector of triode T2 through resistance R8, the emitter of triode T2 ground connection, the collector of triode T2 was both
It is connected with the ends voltage V1 through resistance R9 and is connected with the anode of electrolytic capacitor C10, the cathode of electrolytic capacitor C10 is both through capacitance C11
Ground connection is connected with a fixing end of adjustable resistance RP2 again, another fixing end ground connection of adjustable resistance RP2, adjustable resistance RP2
Movable end be connected with the inverting input of amplifier U, the in-phase input end of amplifier U ground connection, the one end at the ends voltage V1 and resistance R7
It is connected, the other end of resistance R7 not only with the anode of battery BT was connected through electrolytic capacitor C9 ground connection but also through switch K, the output of amplifier U
End is connected with the anode of electrolytic capacitor C13, and the cathode of electrolytic capacitor C13 is connected with the anode of earphone socket CK, earphone socket CK
Cathode ground connection, feedback capacity C12 is also associated on amplifier U, amplifier U uses LM386 operational amplifiers, electrolysis in the present embodiment
The anode of capacitance C7 is connected with the ends voltage V1, and the cathode ground connection of electrolytic capacitor C7, adjustable resistance RP2 and adjustable resistance RP1 are used
The duplex potentiometer coaxially controlled is exactly the volume adjustment knob 12 in Fig. 1.
When needing to survey big sound face, single-direction and dual-direction change-over switch S is controlled, so that its 2 foot and 1 foot is connected, then upright antenna and magnetism
Antenna L1 is connected, and is adjusted tuning capacitance C1, is made antenna loop resonance in 3.53MHz, upright antenna received signal passes through magnetism
Antenna L1 is coupled to magnetic antenna L2, then is conveyed to high-frequency amplifying unit.When the big sound face of accident, magnetic antenna need not be accessed
L1 controls single-direction and dual-direction change-over switch S, so that its 2 foot and 3 feet is connected, then upright antenna is directly connected with magnetic antenna L2, upright day
Line received signal is conveyed to high-frequency amplifying unit again by magnetic antenna L2.Direction-finder antenna receive that radio station sends out 3.5~
After the able one signal of 3.6MHz, send to high-frequency amplifying unit and be amplified, amplified signal and adjustable signal generator based on heter rodyne action
The second harmonic of the oscillator signal of the 1.75~1.8MHz generated is added to difference frequency detection unit together, adjusts the frequency of signal generator based on heter rodyne action
Rate makes it generate the signal more high or low 1KHz than receiving signal, the output signal progress difference frequency of this signal and high-frequency amplifying unit
Detection, obtains the low frequency signal of 1KHz, then send to audio amplification unit and is amplified again, and ear is given finally by earphone interface
Machine, the telegraphic signal that sportsman can be sent out by earphone uppick radio station.Adjustable signal generator based on heter rodyne action uses electric tuning mode,
By adjusting table adjusting knob (adjustable resistance RP3), change the bias voltage that is added on varactor D2 to change two pole of transfiguration
The capacitance at the both ends pipe D2 achievees the purpose that adjust platform, while playing the role of channel selection and beat to change frequency of oscillation.Pass through
Volume adjustment knob is adjusted, i.e., adjusts adjustable resistance RP1 and adjustable resistance RP2 simultaneously, adjustment adjustable resistance RP1 can control height to put
Level work point achievees the purpose that the high amplification gain of control, so that channels watcher height in close-table area strong signal is put grade and do not hinder
Phenomenon is filled in, remains to maintain normally to amplify and keep good directionality, adjusts adjustable resistance RP2, the audio of output can be changed
The volume of signal.
The present invention only with an adjustable signal generator based on heter rodyne action, directly it is poor go out low frequency signal, while playing the role of channel selection and beat,
Grade is put in without this vibration level, intermediate frequency conversion and processing circuit is omitted, circuit is simple, and cost is relatively low, using flexible, radio
Reception ability is strong, and being suitble to compete under the particular surroundings such as mountainous region uses, and use scope is wide, meets direction-finding station under various environment
The needs of movement.
Claims (7)
1. a kind of short distance 3.5MHz channels watchers, it is characterised in that the control including shell (1) and in shell (1)
Circuit, control circuit include direction-finder antenna (2), high-frequency amplifying unit (3), adjustable signal generator based on heter rodyne action (4), difference frequency detection unit
(5) it is connected with the input terminal of high-frequency amplifying unit (3) with audio amplification unit (6), direction-finder antenna (2), high-frequency amplifying unit (3)
Output end and the output end of adjustable signal generator based on heter rodyne action (4) be connected respectively with the input terminal of difference frequency detection unit (5), difference frequency detection
The output end of unit (5) is connected with the input terminal of audio amplification unit (6), and the output end and earphone of audio amplification unit (6) connect
Mouth (7) is connected；The adjustable signal generator based on heter rodyne action (4) include beat oscillator coil B2, triode T3, varactor D2, can
Adjust resistance RP3 and voltage-stabiliser tube D3, a fixing end of the collector of triode T3 and the cathode of voltage-stabiliser tube D3, adjustable resistance RP3
It is connected and connects the ends voltage V1, another fixing end of adjustable resistance RP3 connects the ends voltage V2 through resistance R14, voltage-stabiliser tube D3's
Anode also connects the ends voltage V2, and the emitter of triode T3 connects the ends voltage V2, capacitance through the parallel circuit of resistance R12 and capacitance C18
C17 and voltage-stabiliser tube D3 are in parallel, and the movable end of adjustable resistance RP3 is connected with one end of capacitance C20 and resistance R13, and capacitance C20's is another
One end is connected with the cathode of voltage-stabiliser tube D3, and the other end of resistance R13 is connected with the cathode of varactor D2, varactor D2
Anode connect the ends voltage V2, one end of resistance R10 is connected with the collector of triode T3, one end of capacitance C16 and triode T3
Emitter be connected, the other end of resistance R10 and capacitance C16 are connected with one end of resistance R11, another termination of resistance R11
The base stage at the ends voltage V2, triode T3 is connected with one end of the primary coil of beat oscillator coil B2, beat oscillator coil B2's
The other end of primary coil had not only connect the ends voltage V2 through capacitance C14 but also had been connected with the cathode of varactor D2 through capacitance C15, beat
One end of the secondary wire coil of oscillator coil B2 is connected with the input terminal of the difference frequency detection unit (5), beat oscillator coil B2
Secondary wire coil the ends another termination voltage V2.
2. short distance 3.5MHz channels watchers according to claim 1, it is characterised in that the audio amplification is single
First (6) include audio pre-amplifier unit (8) and Audio power amplifier unit (9), the input terminal of audio pre-amplifier unit (8)
It is connected with the output end of the difference frequency detection unit (5), the output end of audio pre-amplifier unit (8) and the audio work(
The input terminal of rate amplifying unit (9) is connected, and the output end of Audio power amplifier unit (9) is connected with the earphone interface (7).
3. short distance 3.5MHz channels watchers according to claim 1 or 2, it is characterised in that the difference frequency detection
Unit (5) includes detection tube D1, by capacitance C5, capacitance C6 and resistance the R5 filter circuit constituted and detection load resistance R6, inspection
The anode of wave duct D1 is connected with the output end of the high-frequency amplifying unit (3), and the cathode of detection tube D1 was both grounded through capacitance C5
It is connected again with one end of resistance R5, the other end of resistance R5 was not only connected but also passed through with the input terminal of the audio amplification unit (6)
Capacitance C6 ground connection, detection load resistance R6 and capacitance C6 are in parallel.
4. short distance 3.5MHz channels watchers according to claim 2, it is characterised in that the High frequency amplification list
First (3) include triode T1, high unwrapping wire circle B1 and adjustable resistance RP1, the base stage of triode T1, all the way through capacitance C2 and described
The output end of direction-finder antenna (2) is connected, and another way is grounded through resistance R2, the also work through resistance R1 and adjustable resistance RP1 all the way
Moved end is connected, and the fixing end ground connection of adjustable resistance RP1, another fixing end of adjustable resistance RP1 is connected with the ends voltage V1,
The emitter of triode T1 is grounded through the parallel circuit of capacitance C4 and resistance R3, the collector of triode T1 and high unwrapping wire circle B1's
One end of primary coil is connected, the parallel connection of primary windings of capacitance C3 and high unwrapping wire circle B1, in the primary coil of high unwrapping wire circle B1
Tap had not only been connected with the ends voltage V1 through resistance R4 but also had been grounded through capacitance C19, the secondary coil and the difference frequency of high unwrapping wire circle B1
The input terminal of detection unit (5) is connected.
5. short distance 3.5MHz channels watchers according to claim 4, it is characterised in that put before the audio
Big unit (8) includes triode T2, and the Audio power amplifier unit (9) includes adjustable resistance RP2 and amplifier U, triode
The base stage of T2 had not only been connected with the output end of the difference frequency detection unit (5) through capacitance C8 but also the collection through resistance R8 and triode T2
Electrode is connected, and the emitter ground connection of triode T2, the collector of triode T2 had not only been connected with the ends voltage V1 through resistance R9 but also and electricity
The anode for solving capacitance C10 is connected, the cathode of electrolytic capacitor C10 not only through capacitance C11 ground connection again with a fixation of adjustable resistance RP2
End is connected, another fixing end ground connection of adjustable resistance RP2, the movable end of adjustable resistance RP2 and the inverting input phase of amplifier U
Even, the in-phase input end ground connection of amplifier U, the ends voltage V1 are connected with one end of resistance R7, and the other end of resistance R7 is both through electrolysis electricity
Hold C9 ground connection to be again connected with the anode of battery BT through switch K, the output end of amplifier U is connected with the anode of electrolytic capacitor C13, electrolysis
The cathode of capacitance C13 is connected with the anode of earphone socket CK, the cathode ground connection of earphone socket CK, and feedback is also associated on amplifier U
Capacitance C12, adjustable resistance RP2 and adjustable resistance RP1 are using the duplex potentiometer coaxially controlled.
6. short distance 3.5MHz channels watchers according to claim 1 or 2, it is characterised in that the direction-finder antenna
(2) include upright antenna (21), single-direction and dual-direction change-over switch S and the magnetic antenna L1 being mutually coupled and magnetic antenna L2, upright day
Line (21) is connected with the public foot of single-direction and dual-direction change-over switch S, a haptic element of single-direction and dual-direction change-over switch S through phase modulation resistance R15 and
The series circuit of tuning capacitance C1 is grounded, and magnetic antenna L1 and tuning capacitance C1 are in parallel, and another of single-direction and dual-direction change-over switch S touches
One end of foot and magnetic antenna L2 are grounded, the input terminal of the other end and the high-frequency amplifying unit (3) of magnetic antenna L2
It is connected.
7. short distance 3.5MHz channels watchers according to claim 6, it is characterised in that the shell (1) is in length
Cube, the upright antenna (21) are set to the top surface of shell (1), the left side of shell (1), right side respectively there are one protrusion to the left,
The protective cover (10) of the cylindrical shape protruded to the right, two protective covers (10) are close to the top of shell (1), the magnetic antenna
L1 and magnetic antenna L2 be located at the protective cover (10) in left side, right side protective cover (10) in, the left side of shell (1), which is equipped with, adjusts
Platform knob (11) and volume adjustment knob (12), the single-direction and dual-direction change-over switch S use push switch (13), and push type is opened
The right side that (13) are located at shell (1) is closed, the earphone interface (7) is using the earphone interface with power switch, earphone interface
(7) it is located at the right side of shell (1).
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| Application Number | Priority Date | Filing Date | Title |
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| CN201510345146.4A CN105101012B (en) | 2015-06-18 | 2015-06-18 | Short distance 3.5MHz channels watchers |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201510345146.4A CN105101012B (en) | 2015-06-18 | 2015-06-18 | Short distance 3.5MHz channels watchers |
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| CN105101012A CN105101012A (en) | 2015-11-25 |
| CN105101012B true CN105101012B (en) | 2018-07-31 |
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| CN109444600A (en) * | 2018-12-11 | 2019-03-08 | 国网河南省电力公司南阳供电公司 | Track instrument is sought in a kind of high frequency carrier injection type low-voltage circuit path |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN200968988Y (en) * | 2006-01-10 | 2007-10-31 | 甄书义 | 144MHz wave band radio direction finding machine |
| CN204795565U (en) * | 2015-06-18 | 2015-11-18 | 金艾炜 | Short distance 3. 5MHz radio direction finding machine |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB0300352D0 (en) * | 2003-01-08 | 2003-02-05 | Secr Defence | Radio signal direction finder |
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2015
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN200968988Y (en) * | 2006-01-10 | 2007-10-31 | 甄书义 | 144MHz wave band radio direction finding machine |
| CN204795565U (en) * | 2015-06-18 | 2015-11-18 | 金艾炜 | Short distance 3. 5MHz radio direction finding machine |
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| CN105101012A (en) | 2015-11-25 |
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