FMUSER RF Fais Amplifier Voltage Test Bench rau AM Transmitter Fais Fab Amplifier (PA) thiab Tsis Siv Neeg Amplifier Test

RF Fais Amplifier Board Test | AM Commissioning Solution los ntawm FMUSER

 

RF fais fab amplifiers thiab tsis amplifiers yog qhov tseem ceeb tshaj plaws ntawm AM transmitters thiab ib txwm ua lub luag haujlwm tseem ceeb hauv kev tsim, xa khoom, thiab kev tu tom qab.

 

Cov khoom siv yooj yim no pab kom muaj kev sib kis ntawm RF teeb liab. Nyob ntawm lub zog theem thiab lub zog xav tau los ntawm tus neeg txais khoom los txheeb xyuas thiab txiav txim siab lub teeb liab, txhua qhov kev puas tsuaj tuaj yeem tawm hauv xov tooj cua nrog cov teeb liab distortion, txo hwj chim noj, thiab ntau dua.

 

 

Rau kev kho dua tshiab tom qab thiab kev saib xyuas cov ntsiab lus tseem ceeb ntawm cov khoom xa tawm, qee cov khoom siv ntsuas tseem ceeb yog qhov tseem ceeb. FMUSER's RF ntsuas kev daws teeb meem pab koj txheeb xyuas koj tus qauv tsim los ntawm kev ntsuas RF tsis sib xws.

 

Yuav ua li cas nws hauj lwm

 

Nws yog tsuas yog siv rau kev ntsuam xyuas thaum lub hwj chim amplifier board thiab buffer amplifier board ntawm AM transmitter tsis tuaj yeem paub tseeb tias tom qab kho.

 

 

nta

 

• Lub hwj chim ntawm qhov ntsuas lub rooj zaum yog AC220V, thiab lub vaj huam sib luag muaj lub zog hloov. Internally generated -5v, 40v, thiab 30v yog muab los ntawm lub built-in switching fais fab mov.
• Muaj cov khoom tso zis tsis zoo Q9 cuam tshuam rau sab sauv ntawm lub rooj zaum sim: J1 thiab J2, lub zog amplifier tso zis kuaj Q9 interfaces: J1 thiab J2, thiab lub zog amplifier voltage ntsuas (59C23). J1 thiab J2 txuas nrog ob lub oscilloscope.
• Sab laug ntawm sab qis ntawm lub rooj sib tw xeem yog qhov ntsuas qhov ntsuas qhov tsis txaus, thiab sab xis yog lub zog amplifier pawg thawj coj kuaj.

 

Cov lus qhia

 

• J1: Ntsuas lub hwj chim hloov
• S1: Amplifier board test thiab buffer board test selector switch
• S3 / S4: Fais fab amplifier board kuaj sab laug thiab txoj cai tig-on teeb liab tig-on lossis xaiv xaiv xaiv.

 

RF Fais Amplifier: Nws yog dab tsi thiab nws ua haujlwm li cas?

 

Hauv xov tooj cua, RF fais fab amplifier (RF PA), lossis xov tooj cua zaus lub zog amplifier yog ib qho khoom siv hluav taws xob uas siv los ua kom nrov nrov thiab tso tawm cov ntsiab lus, uas feem ntau qhia raws li qhov hluav taws xob lossis lub zog, thaum lub zog RF lub zog amplifier txoj haujlwm yog nce. cov khoom nws "absorbs" rau ib theem twg thiab "export nws mus rau lub ntiaj teb sab nraud."

 

Nws Ua Haujlwm Li Cas?

 

Feem ntau, RF fais fab amplifier yog tsim rau hauv lub transmitter nyob rau hauv daim ntawv ntawm ib tug Circuit Court board. Tau kawg, RF fais fab amplifier tuaj yeem yog ib qho khoom sib cais txuas nrog cov khoom siv hluav taws xob qis hluav taws xob los ntawm coaxial cable. Vim qhov chaw txwv, yog tias koj xav tau, txais tos sau ntawv tawm thiab kuv yuav hloov kho nws ib hnub yav tom ntej :).

 

Qhov tseem ceeb ntawm RF fais fab amplifier yog kom tau txais lub zog loj txaus RF tso zis. Qhov no yog vim hais tias, ua ntej ntawm tag nrho cov, nyob rau hauv pem hauv ntej-kawg Circuit Court ntawm lub transmitter, tom qab lub suab teeb liab yog input los ntawm lub suab los ntawm cov ntaub ntawv kab, nws yuav hloov dua siab tshiab rau hauv ib tug tsis muaj zog RF teeb liab los ntawm kev hloov kho, tab sis cov tsis muaj zog. cov teeb liab tsis txaus los ua kom tau raws li qhov kev tshaj tawm xov xwm loj. Yog li ntawd, cov RF modulated signals mus los ntawm ib tug series ntawm amplification (buffer theem, intermediate amplification theem, zaum kawg lub hwj chim amplification theem) los ntawm lub RF fais fab amplifier kom txog rau thaum nws yog amplified mus rau lub hwj chim txaus thiab ces dhau los ntawm kev sib txuam network. Thaum kawg, nws tuaj yeem pub rau lub kav hlau txais xov thiab tawg tawm.

 

Rau kev ua haujlwm receiver, lub transceiver lossis transmitter-receiver unit tuaj yeem muaj qhov hloov pauv sab hauv lossis sab nraud / tau txais (T / R). Txoj haujlwm ntawm T / R hloov pauv yog hloov lub kav hlau txais xov mus rau lub transmitter lossis receiver raws li xav tau.

 

Dab tsi yog Cov Qauv Tseem Ceeb ntawm RF Fais Amplifier?

 

Cov kev qhia tseem ceeb ntawm RF fais fab amplifiers yog cov zis hluav taws xob thiab kev ua haujlwm zoo. Yuav ua li cas los txhim kho cov zis hluav taws xob thiab kev ua haujlwm zoo yog qhov tseem ceeb ntawm cov hom phiaj tsim ntawm RF fais fab amplifiers.

 

RF fais fab amplifier muaj ib qho kev khiav hauj lwm zaus, thiab xaiv qhov kev khiav hauj lwm zaus yuav tsum nyob rau hauv nws ntau zaus. Rau kev khiav hauj lwm zaus ntawm 150 megahertz (MHz), RF fais fab amplifier nyob rau hauv thaj tsam ntawm 145 txog 155 MHz yuav tsim nyog. RF fais fab amplifier nrog ntau zaus ntawm 165 txog 175 MHz yuav tsis tuaj yeem ua haujlwm ntawm 150 MHz.

 

Feem ntau, hauv RF fais fab amplifier, qhov tseem ceeb zaus los yog ib qho kev sib haum xeeb tuaj yeem raug xaiv los ntawm LC resonant circuit kom ua tiav distortion-dawb amplification. Ntxiv rau qhov no, cov khoom sib haum xeeb hauv cov zis yuav tsum tsawg li tsawg tau kom tsis txhob cuam tshuam nrog lwm cov channel.

 

RF fais fab amplifier circuits tuaj yeem siv cov transistors lossis kev sib txuas ua ke los tsim kom muaj kev nthuav dav. Nyob rau hauv RF lub zog amplifier tsim, lub hom phiaj yog kom muaj kev nthuav dav txaus los tsim cov khoom siv hluav taws xob uas xav tau, thaum tso cai rau ib ntus thiab me me tsis sib haum ntawm lub transmitter thiab kav hlau txais xov feeder thiab kav hlau txais xov nws tus kheej. Lub impedance ntawm tus kav hlau txais xov feeder thiab tus kav hlau txais xov nws tus kheej feem ntau yog 50 ohms.

 

Qhov zoo tshaj plaws, lub kav hlau txais xov thiab cov kab pub khoom sib xyaw ua ke yuav nthuav tawm cov impedance ntawm kev ua haujlwm zaus.

Vim li cas RF Fais Amplifier thiaj li tsim nyog?

 

Raws li qhov tseem ceeb ntawm kev xa xov, qhov tseem ceeb ntawm RF fais fab amplifier yog qhov tseeb. Peb txhua tus paub tias tus kws tshaj lij tshaj tawm xov xwm feem ntau suav nrog cov hauv qab no:

 

1. Rigid plhaub: feem ntau yog ua los ntawm aluminium alloy, tus nqi siab dua.
2. Suab input board: feem ntau yog siv los muab cov teeb liab tawm tswv yim los ntawm lub suab, thiab txuas lub transmitter thiab lub suab los ntawm lub suab cable (xws li XLR, 3.45MM, thiab lwm yam). Lub rooj tsavxwm lub suab feem ntau yog muab tso rau hauv qab vaj huam sib luag ntawm lub transmitter thiab yog ib lub voj voos sib luag nrog qhov sib piv ntawm kwv yees li 4: 1.
3. Fais fab mov: Nws yog siv rau lub hwj chim mov. Ntau lub teb chaws muaj cov qauv siv hluav taws xob sib txawv, xws li 110V, 220V, thiab lwm yam. Hauv qee lub xov tooj cua loj, cov khoom siv hluav taws xob ntau yog 3 Phase 4 Wire System (380V / 50Hz) raws li tus qauv. Nws kuj yog ib thaj av muaj kev lag luam raws li tus qauv, uas txawv ntawm cov qauv hluav taws xob hauv pej xeem.
4. Control vaj huam sib luag thiab modulator: feem ntau yog nyob rau hauv lub feem ntau conspicuous txoj hauj lwm nyob rau hauv pem hauv ntej vaj huam sib luag ntawm lub transmitter, muaj li ntawm installation vaj huam sib luag thiab ib co muaj nuj nqi yuam sij (nob, tswj tuav, zaub screen, thiab lwm yam), mas siv los hloov lub suab input teeb liab. rau hauv RF teeb liab (yooj yim heev).
5. RF fais fab amplifier: feem ntau yog hais txog lub hwj chim amplifier pawg thawj coj saib, uas yog tsuas yog siv los ua kom muaj zog RF teeb liab tsis muaj zog los ntawm qhov kev hloov pauv. Nws muaj cov PCB thiab cov txheej txheem ntawm cov khoom siv sib txuas (xws li RF input kab, lub zog amplifier chips, lim, thiab lwm yam), thiab Nws txuas nrog lub kav hlau txais xov feeder los ntawm RF tso zis interface.
6. Fais fab mov thiab kiv cua: Cov lus qhia tshwj xeeb yog tsim los ntawm cov chaw tsim khoom siv hluav taws xob, feem ntau yog siv rau cov khoom siv hluav taws xob thiab cov cua sov dissipation

 

Ntawm lawv, RF fais fab amplifier yog qhov tseem ceeb tshaj plaws, kim tshaj plaws, thiab qhov yooj yim tshaj plaws hlawv ib feem ntawm lub transmitter, uas yog txiav txim siab los ntawm nws ua haujlwm li cas: qhov tso zis ntawm RF lub zog amplifier yog txuas nrog lub kav hlau txais xov sab nraud.

 

Feem ntau cov kav hlau txais xov tuaj yeem hloov kho kom thaum ua ke nrog lub feeder, lawv muab qhov zoo tshaj plaws impedance rau lub transmitter. Qhov kev sib txuam impedance no yog xav tau rau lub zog siab tshaj plaws ntawm lub transmitter mus rau lub kav hlau txais xov. Antennas muaj cov yam ntxwv sib txawv me ntsis hauv qhov ntau zaus. Ib qho kev sim tseem ceeb yog los xyuas kom meej tias lub zog ntawm lub zog ntawm lub kav hlau txais xov mus rau lub feeder thiab rov qab mus rau lub transmitter yog tsawg txaus. Thaum lub impedance tsis sib haum yog siab dhau lawm, lub zog RF xa mus rau lub kav hlau txais xov tuaj yeem rov qab mus rau lub transmitter, tsim kom muaj qhov sib piv siab yoj (SWR), ua rau lub zog xa hluav taws xob nyob hauv RF lub zog amplifier, ua rau overheating thiab txawm tias muaj kev puas tsuaj rau kev ua haujlwm. cov khoom.

 

Yog hais tias lub amplifier muaj peev xwm ua tau zoo, ces nws tuaj yeem pab txhawb ntxiv, uas qhia txog nws tus kheej "tus nqi", tab sis yog tias muaj qee yam teeb meem nrog lub amplifier, tom qab pib ua haujlwm lossis ua haujlwm rau lub sijhawm, tsis tsuas yog nws tsis tuaj yeem ua haujlwm. Ntev dua Muab ib qho "kev koom tes", tab sis tej zaum yuav muaj qee qhov kev npaj txhij txog "kev poob siab". Xws li "kev poob siab" yog kev puas tsuaj rau lub ntiaj teb sab nraud lossis lub tshuab hluav taws xob nws tus kheej.

 

Buffer amplifier: Nws yog dab tsi thiab nws ua haujlwm li cas?

 

Buffer amplifiers yog siv hauv AM transmitters.

 

Lub AM transmitter muaj ib theem oscillator, ib tug tsis thiab multiplier theem, ib tug tsav tsheb theem, thiab ib tug modulator theem, qhov twg lub ntsiab oscillator powers lub tsis amplifier, ua raws li los ntawm lub buffer theem.

 

Cov theem ntawm lub oscillator yog hu ua ib tug tsis los yog tsis amplifier (qee zaus hu ua ib tug tsis) - yog li lub npe vim hais tias nws cais lub oscillator los ntawm lub hwj chim amplifier.

 

Raws li Wikipedia, lub tshuab hluav taws xob tsis yog lub tshuab hluav taws xob uas muab hluav taws xob hloov pauv hluav taws xob los ntawm ib lub voj voog mus rau lwm qhov txhawm rau tiv thaiv lub teeb liab los ntawm txhua qhov tam sim no (los yog qhov hluav taws xob, rau qhov tsis muaj tam sim no) uas cov khoom yuav tsim.

 

Nyob rau hauv qhov tseeb, nyob rau hauv lub transmitter sab, tsis amplifier yog siv los cais lub ntsiab oscillator los ntawm lwm theem ntawm lub transmitter, tsis muaj tsis, thaum lub hwj chim amplifier hloov, nws yuav xav rov qab mus rau lub oscillator thiab ua rau nws hloov zaus, thiab yog hais tias lub oscillation Yog hais tias lub transmitter hloov lub zaus, tus receiver yuav plam kev sib cuag nrog lub transmitter thiab tau txais cov ntaub ntawv tsis tiav.

 

Nws Ua Haujlwm Li Cas?

 

Lub ntsiab oscillator nyob rau hauv AM transmitter tsim ib tug ruaj khov sub-harmonic cab kuj zaus. Cov siv lead ua oscillator yog siv los tsim qhov ruaj khov sub-harmonic oscillation. Tom qab ntawd, qhov zaus yog nce mus rau qhov xav tau los ntawm kev siv lub tshuab hluav taws xob sib haum xeeb. Tus cab kuj zaus yuav tsum ruaj khov heev. Ib qho kev hloov pauv hauv qhov zaus no tuaj yeem ua rau cuam tshuam rau lwm qhov chaw xa khoom. Yog li ntawd, tus txais yuav txais cov kev pab cuam los ntawm ntau lub transmitters.

 

Tuned amplifiers uas muab siab input impedance ntawm lub ntsiab oscillator zaus yog tsis amplifiers. Nws pab tiv thaiv txhua qhov kev hloov pauv hauv kev thauj khoom tam sim no. Vim nws cov input impedance siab nyob rau hauv kev khiav hauj lwm zaus ntawm lub ntsiab oscillator, kev hloov tsis cuam tshuam rau lub ntsiab oscillator. Yog li ntawd, lub buffer amplifier cais lub ntsiab oscillator los ntawm lwm theem kom loading teebmeem tsis hloov lub zaus ntawm lub ntsiab oscillator.

 

RF Fais Amplifier Test Bench: Nws yog dab tsi thiab nws ua haujlwm li cas

 

Lub sij hawm "test bench" siv cov lus piav qhia kho vajtse hauv cov qauv tsim los piav qhia cov lej xeem uas ua rau DUT thiab khiav cov kev xeem.

 

Xeem Raug Tshem Tawm

 

Lub rooj ntev zaum sim lossis kuaj workbench yog ib puag ncig siv los txheeb xyuas qhov tseeb lossis kev huv ntawm tus qauv tsim lossis qauv.

 

Lub sij hawm pib los ntawm kev ntsuam xyuas cov khoom siv hluav taws xob, qhov twg tus kws ua haujlwm yuav zaum ntawm lub rooj zaum hauv chav kuaj, tuav kev ntsuas thiab tswj cov cuab yeej xws li oscilloscopes, multimeters, soldering irons, hlau cutters, thiab lwm yam. (DUT).

 

Nyob rau hauv cov ntsiab lus ntawm software lossis firmware lossis hardware engineering, lub rooj ntev zaum sim yog ib puag ncig uas cov khoom lag luam nyob rau hauv kev txhim kho raug sim nrog kev pab ntawm software thiab cov cuab yeej kho vajtse. Qee zaum, cov software yuav xav tau kev hloov kho me me los ua haujlwm nrog testbench, tab sis ceev faj coding kom ntseeg tau tias cov kev hloov pauv tuaj yeem yooj yim undone thiab tsis muaj kab laum.

 

Lwm lub ntsiab lus ntawm "test bed" yog ib qho kev sib cais, tswj ib puag ncig, zoo ib yam li ib puag ncig kev tsim khoom, tab sis tsis zais los yog tsis pom rau cov pej xeem, cov neeg siv khoom, thiab lwm yam. Nws yog qhov muaj kev nyab xeeb rau kev hloov pauv vim tsis muaj cov neeg siv khoom kawg.

 

RF Device nyob rau hauv Test (DUT)

 

Ib qho cuab yeej nyob rau hauv kev xeem (DUT) yog ib qho cuab yeej uas tau raug sim los txiav txim siab txog kev ua tau zoo thiab kev ua tau zoo. DUT kuj tuaj yeem yog ib feem ntawm cov qauv loj dua lossis chav hu ua chav nyob hauv kev sim (UUT). Tshawb xyuas DUT rau qhov tsis xws luag kom paub tseeb tias lub cuab yeej ua haujlwm zoo. Qhov kev sim no yog tsim los tiv thaiv cov khoom puas los ntawm kev mus txog lub khw, uas tuaj yeem txo cov nqi tsim khoom.

 

Ib qho khoom siv hauv kev sim (DUT), tseem hu ua cov cuab yeej nyob rau hauv kev sim (EUT) thiab ib chav nyob hauv kev sim (UUT), yog cov khoom lag luam tshuaj ntsuam xyuas uas tau sim thaum thawj zaug tsim lossis tom qab hauv nws lub neej raws li ib feem ntawm kev sim ua haujlwm tsis tu ncua thiab calibration. Qhov no tuaj yeem suav nrog kev kuaj tom qab kho kom txiav txim siab seb cov khoom puas ua tau raws li cov khoom lag luam tshwj xeeb.

 

Hauv kev ntsuam xyuas semiconductor, cov cuab yeej nyob rau hauv kev sim yog tuag ntawm wafer lossis qhov kawg ntim. Siv cov txheej txheem kev sib txuas, txuas cov khoom siv rau cov khoom siv tsis siv neeg lossis phau ntawv xeem. Cov cuab yeej kuaj tom qab ntawd ua rau lub zog tivthaiv, muab cov cim qhia kev txhawb zog, thiab ntsuas thiab ntsuas cov khoom tsim tawm. Ua li no, tus tester txiav txim siab seb cov cuab yeej tshwj xeeb hauv kev sim ua tau raws li cov khoom siv tshwj xeeb.

 

Feem ntau, RF DUT tuaj yeem yog ib qho kev tsim hluav taws xob nrog kev sib xyaw ua ke thiab muaj pes tsawg tus analog thiab RF Cheebtsam, transistors, resistors, capacitors, thiab lwm yam, haum rau simulation nrog Agilent Circuit Envelope Simulator. Ntau RF circuits yuav siv sij hawm ntau dua los simulate thiab haus ntau lub cim xeeb.

 

Testbench simulation lub sij hawm thiab lub cim xeeb yuav tsum tau xav txog raws li ib tug ua ke ntawm cov benchmark testbench ntsuas nrog rau qhov yuav tsum tau ntawm qhov yooj yim RF Circuit Court ntxiv rau lub Circuit Court simulation cov cai ntawm RF DUT ntawm kev txaus siab.

 

Ib qho RF DUT txuas nrog lub rooj ntev zaum sim wireless feem ntau tuaj yeem siv nrog lub rooj zaum sim los ua qhov kev ntsuas tsis zoo los ntawm kev teeb tsa qhov ntsuas qhov ntsuas qhov ntsuas. Default ntsuas parameter nqis muaj rau ib tug raug RF DUT:

 

• Yuav tsum muaj ib qho kev tawm tswv yim (RF) teeb liab nrog lub xov tooj cua tsis tu ncua ntawm tus neeg nqa khoom zaus. Qhov tso zis ntawm lub rooj ntev zaum RF teeb liab qhov chaw tsis tsim RF teeb liab uas nws RF cab kuj sib txawv raws li lub sij hawm. Txawm li cas los xij, lub rooj ntev zaum sim yuav txhawb nqa cov teeb liab tso zis uas muaj RF cov cab kuj theem thiab zaus hloov kho, uas tuaj yeem sawv cev los ntawm qhov tsim nyog I thiab Q lub hnab ntawv hloov pauv ntawm qhov tsis tu ncua RF cov cab kuj zaus.
• Lub teeb liab tso zis nrog lub RF tus cab kuj zaus yog tsim. Qhov ntsuas lub rooj zaum lub teeb liab tawm tswv yim yuav tsum tsis muaj cov cab kuj zaus uas nws zaus sib txawv raws sij hawm. Txawm li cas los xij, lub rooj ntev zaum sim yuav txhawb cov tswv yim tawm tswv yim uas muaj cov suab nrov ntawm RF los yog lub sij hawm sib txawv Doppler hloov ntawm RF cab kuj. Cov teeb liab perturbations yuav tsum tau sawv cev los ntawm qhov tsim nyog I thiab Q lub hnab ntawv hloov pauv ntawm qhov tsis tu ncua RF cov cab kuj zaus.
• Lub teeb liab tawm tswv yim los ntawm lub teeb liab lub tshuab hluav taws xob nrog 50-ohm qhov chaw tiv thaiv yuav tsum tau ua.
• Yuav tsum muaj lub teeb liab input yam tsis muaj spectral mirroring.
• Tsim cov teeb liab tso zis uas yuav tsum tau muaj kev tiv thaiv sab nraud ntawm 50 ohms.
• Tsim cov teeb liab tso zis yam tsis muaj spectral mirroring.
• Cia siab rau ntawm lub rooj ntev zaum sim los ua ib qho kev ntsuas ntsuas cuam tshuam txog bandpass teeb liab lim ntawm RF DUT tso zis teeb liab.

 

AM Transmitter Basics Koj Yuav Tsum Paub

 

Lub transmitter uas tso tawm AM teeb liab hu ua AM transmitter. Cov transmitters yog siv nyob rau hauv nruab nrab yoj (MW) thiab luv yoj (SW) zaus bands ntawm AM tshaj tawm. MW band muaj zaus ntawm 550 kHz thiab 1650 kHz thiab SW band muaj zaus ntawm 3 MHz txog 30 MHz.

 

Ob hom AM transmitters siv raws li lub zog xa tawm yog:

 

1. theem siab
2. qes theem

 

High-level transmitters siv high-level modulation, thiab low-level transmitters siv low-level modulation. Qhov kev xaiv ntawm ob qhov kev hloov pauv yog nyob ntawm lub zog xa tawm ntawm AM transmitter. Hauv kev tshaj tawm xov tooj cua uas nws lub zog xa tawm tuaj yeem nyob ntawm qhov kev txiav txim ntawm kilowatts, qib siab hloov kho yog siv. Hauv cov khoom siv hluav taws xob qis uas tsuas yog xav tau ob peb watts ntawm lub zog xa hluav taws xob, kev hloov pauv qis yog siv.

 

High thiab low-level transmitters

 

Daim duab hauv qab no qhia txog daim duab thaiv ntawm cov qib siab thiab qib qis transmitters. Qhov sib txawv ntawm ob lub transmitters yog lub zog amplification ntawm cov cab kuj thiab cov teeb liab modulated.

 

Daim duab (a) qhia ib daim duab thaiv ntawm ib qho kev tshaj AM transmitter.

 

Daim duab (a) yog kos rau kev xa suab. Nyob rau hauv high-theem kis tau tus mob, lub hwj chim ntawm cov cab kuj thiab modulated signals yog amplified ua ntej yuav siv rau lub modulator theem, raws li qhia nyob rau hauv daim duab (a). Nyob rau hauv qis-theem modulation, lub hwj chim ntawm ob input signals mus rau lub modulator theem tsis amplified. Lub zog xa hluav taws xob yuav tsum tau txais los ntawm theem kawg ntawm lub transmitter, Class C lub zog amplifier.

 

Cov seem ntawm daim duab (a) yog:

 

1. Carrier Oscillator
2. Tsis Siv Neeg Amplifier
3. Ntau zaus
4. Fais Amplifier
5. Audio Chain
6. Modulated Class C Fais Amplifier
7. Carrier Oscillator

 

Tus cab kuj oscillator tsim ib lub teeb liab cab kuj nyob rau hauv lub xov tooj cua zaus ntau. Qhov zaus ntawm tus cab kuj yog ib txwm siab. Txij li thaum nws yog ib qho nyuaj los tsim cov high zaus nrog zoo zaus stability, carrier oscillators tsim submultiples nrog rau qhov xav tau ntau zaus. Qhov no sub-octave yog muab faib los ntawm theem multiplier kom tau txais qhov xav tau tus cab kuj zaus. Tsis tas li ntawd, siv lead ua oscillator tuaj yeem siv nyob rau theem no los tsim kom muaj cov neeg nqa khoom tsawg tsawg nrog qhov zoo tshaj plaws kev ruaj ntseg. Cov theem ntau zaus ces ua rau cov cab kuj nce mus rau nws qhov kev xav tau.

 

Tsis Siv Neeg Amp

 

Lub hom phiaj ntawm qhov tsis muaj amplifier yog ob npaug. Nws thawj zaug sib tw cov zis impedance ntawm cov cab kuj oscillator nrog cov input impedance ntawm tus zaus multiplier, theem tom ntej ntawm cov cab kuj oscillator. Nws ces cais cov cab kuj oscillator thiab zaus multiplier.

 

Qhov no yog qhov tsim nyog kom tus multiplier tsis kos cov dej ntws loj los ntawm cov cab kuj oscillator. Yog tias qhov no tshwm sim, qhov zaus ntawm cov cab kuj oscillator yuav tsis ruaj khov.

 

Ntau zaus

 

Lub sub-multiplied zaus ntawm tus cab kuj teeb liab tsim los ntawm cov cab kuj oscillator yog tam sim no siv rau cov zaus multiplier los ntawm tsis amplifier. Cov theem no tseem hu ua harmonic generator. Qhov ntau zaus ua rau ntau dua kev sib haum xeeb ntawm cov cab kuj oscillator zaus. Ib qho kev sib txuas ntau zaus yog ib lub voj voog tuned uas tig mus rau tus neeg nqa khoom zaus uas yuav tsum tau xa mus.

 

Hwj chim Amp

 

Lub hwj chim ntawm lub teeb liab cov cab kuj yog amplified nyob rau hauv lub hwj chim amplifier theem. Qhov no yog ib qho yuav tsum tau ua rau lub siab transmitter. Class C lub zog amplifiers muab lub zog siab tam sim no pulses ntawm cov teeb liab nqa khoom ntawm lawv cov zis.

Audio Chain

 

Lub suab teeb liab yuav kis tau los ntawm lub microphone raws li qhia hauv daim duab (a). Lub suab tsav amplifier amplifies qhov voltage ntawm lub teeb liab no. Qhov no amplification yog tsim nyog los tsav lub hwj chim amplifiers. Tom ntej no, Chav Kawm A lossis Class B lub zog amplifier ua kom lub zog ntawm lub suab teeb liab.

 

Modulated Class C Amplifier

 

Qhov no yog theem tso zis ntawm lub transmitter. Modulated suab teeb liab thiab cov teeb liab cab kuj yog siv rau qhov kev hloov kho theem tom qab lub zog amplification. Lub modulation tshwm sim nyob rau theem no. Class C amplifier kuj ua kom lub zog ntawm AM teeb liab mus rau lub zog xa rov qab. Qhov teeb liab no yog thaum kawg dhau mus rau lub kav hlau txais xov, uas radiates lub teeb liab mus rau hauv qhov chaw sib kis.

 

Daim duab (b): Tsawg-Qib AM Transmitter Block Diagram

 

Lub low-level AM transmitter qhia nyob rau hauv daim duab (b) zoo ib yam li lub high-level transmitter tshwj tsis yog tias lub hwj chim ntawm cov cab kuj thiab lub suab teeb liab tsis amplified. Ob lub teeb liab no tau siv ncaj qha mus rau qhov hloov pauv Class C lub zog amplifier.

 

Qhov kev hloov kho tau tshwm sim thaum lub sijhawm no, thiab lub zog ntawm cov teeb liab modulated yog amplified mus rau qhov xav tau kev xa hluav taws xob theem. Tus kav hlau txais xov kis tau tus kab mob ces xa cov teeb liab.

 

Coupling ntawm cov zis theem thiab kav hlau txais xov

 

Cov theem tso zis ntawm cov chav kawm C lub hwj chim amplifier muab cov teeb liab mus rau lub kav hlau txais xov xa mus. Txhawm rau hloov lub zog siab tshaj plaws los ntawm theem tso tawm mus rau lub kav hlau txais xov, qhov impedances ntawm ob ntu yuav tsum sib phim. Rau qhov no, yuav tsum muaj qhov sib txuam network. Qhov kev sib tw ntawm ob yuav tsum zoo tag nrho ntawm txhua qhov kev xa tawm zaus. Txij li thaum sib txuam ntawm ntau zaus yuav tsum tau siv, inductors thiab capacitors uas muab cov impedances sib txawv ntawm cov zaus sib txawv yog siv hauv kev sib txuam network.

 

Lub network sib txuam yuav tsum tau tsim los siv cov khoom siv passive no. Raws li pom hauv daim duab (c) hauv qab no.

 

Daim duab (c): Dual Pi txuam network

 

Qhov sib txuam network siv los ua ob peb lub transmitter tso zis theem thiab tus kav hlau txais xov hu ua dual π network. Lub network tau qhia hauv daim duab (c). Nws muaj ob inductors L1 thiab L2 thiab ob lub capacitor C1 thiab C2. Cov txiaj ntsig ntawm cov khoom no raug xaiv kom cov tswv yim impedance ntawm lub network nyob nruab nrab ntawm 1 thiab 1'. Daim duab (c) yog qhia kom phim cov zis impedance ntawm lub transmitter tso zis theem. Tsis tas li ntawd, qhov tso zis impedance ntawm lub network sib phim lub impedance ntawm tus kav hlau txais xov.

 

Ob chav π txuam network kuj lim tawm cov khoom siv zaus tsis xav tau uas tshwm sim ntawm cov zis ntawm theem kawg ntawm lub tshuab xa tawm. Cov zis ntawm lub modulated Class C lub zog amplifier yuav muaj cov kev sib raug zoo siab dua, xws li kev sib haum xeeb thib ob thiab thib peb. Cov lus teb zaus ntawm qhov sib txuam network tau teeb tsa kom tsis lees txais cov kev tsis sib haum xeeb siab dua no thiab tsuas yog cov teeb liab xav tau yog txuas rau lub kav hlau txais xov.