Multimeters thiab txheej txheem calibrators tuaj yeem siv nrog 9V roj teeb.
Multimeter thiab txheej txheem calibrator ntawm cov cuab yeej no feem ntau tsis tshua muaj tam sim no, zoo li cov kev khiav hauj lwm tam sim no ntawm cov multimeter yog feem ntau qis dua 20mA, yog li nws tuaj yeem siv 1.5V qhuav ntawm tes (los yog 1.2V NiMH roj teeb) los ntawm kev txhawb zog los hloov cov 9V stacked roj teeb. Cov nram qab no yog ib qho yooj yim thiab yooj yim los ua 1.5V rau 9V voltage regulator Circuit Court, uas yuav siv tau los hloov lub multimeter 9V stacked roj teeb.
Triode 9013 thiab 8550 tsim ib qho ntxiv rau nws tus kheej-excited multi-harmonic oscillator, ob lub raj ua haujlwm hauv lub xeev hloov. t rau lub kauj ruam-up transformer, thawj kauj raws li 8550 transistor collector load, 8550 collector tso zis oscillating teeb liab los ntawm transformer T step-up, theem nrab ntawm high-frequency alternating tam sim no voltage, lub voltage yog rectified los ntawm Schottky diode. 1N5819, C2 lim thiab voltage regulator VD2 regulator. Qhov voltage yog rectified los ntawm Schottky diode 1N5819, lim los ntawm C2 thiab tswj los ntawm voltage regulator VD2, cov zis ntawm lub Vout davhlau ya nyob twg yog ib tug ruaj khov 9V voltage.
Lub oscillation zaus ntawm qhov Circuit Court no tsuas yog txiav txim siab los ntawm R2 thiab C1. Feem ntau, qhov zaus oscillation tuaj yeem xaiv tau los ntawm 5 txog 20 KHz, thiab qhov tso zis hluav taws xob ntawm lub zog hluav taws xob yog txiav txim siab los ntawm tus nqi tswj hwm ntawm qhov voltage regulator VD2. Yog tias koj xav tau qhov hluav taws xob ruaj khov ntawm 9V, koj tuaj yeem xaiv 1N4739 regulator, tus nqi regulator ntawm 9.1V, lub zog ntawm 1W. vim yog cov zis theem ob ntawm lub transformer yog ib tug high-frequency alternating tam sim no voltage, yog li VD1 yuav tsum tau xaiv nrog high-frequency kev ua tau zoo ntawm lub switching diode los yog Schottky diode. Capacitor C2 yog qhov zoo tshaj plaws siv rau high-frequency filtering zoo tantalum capacitors. qhov loj ntawm R3 nyob ntawm qhov voltage ntawm qhov kawg ntawm C2 thiab qhov tseeb ua haujlwm tam sim no ntawm multimeter. Ntawm no nws yog assumed tias qhov voltage ntawm ob kawg ntawm C2 yog 15V, lub tam sim no ntws los ntawm VD2 yog 10mA, thiab lub siab tshaj plaws kev khiav hauj lwm tam sim no ntawm lub multimeter yog 15mA, ces R3 yuav muab tau raws li ib tug 240Ω resistor.
Lub voj voog ntawm cov kauj ruam-up transformer tuaj yeem xaiv siv lub nplhaib ferrite nyob ib ncig ntawm lub cev, lub nplhaib ferrite tuaj yeem raug tshem tawm ntawm qee qhov ntawm cov khoom siv hluav taws xob los yog hloov cov khoom siv hluav taws xob.
Thaum ua nws, ntawm ob lub transistors loj npaum li qhov ua tau. Lub hwj chim hloov S hauv Circuit Court tuaj yeem siv lub zog hloov ntawm tus thawj multimeter. Lub voj voog tuaj yeem siv tau los ntawm 5 lub xov tooj ntawm tes qhuav lossis 1.2V NiMH roj teeb.
