Kev piav qhia ntawm Dial Composition rau Analog Multimeters
Lub multimeter feem ntau yog siv los ntsuas ntau yam voltages thiab resistances. Nws muaj ib lub dial, ib tug calibration ntsia hlau rau lub 'meter' lub taub hau, ib tug muaj nuj nqi pob qhov rooj, ib tug xoom ohm calibration knob, ib tug transistor nrhiav tau qhov (socket), ib tug sojntsuam qhov (socket), thiab lub npe; Vim hais tias ib tug multimeter muaj ntau lub zog, muaj ntau yam kab thiab qhov tseem ceeb ntawm lub dial ntawm lub multimeter. Raws li pom hauv daim duab hauv qab no, lub xov tooj yog tsim los ntawm 5 concentric arcs, thiab txhua kab kab kuj qhia txog qhov ntsuas tus nqi sib thooj rau cov pob qhov rooj xaiv. Thov xa mus rau cov lus qhia tshwj xeeb hauv qab no
1. Resistance Scale (Ω): Qhov ntsuas tsis kam yog nyob rau sab saum toj ntawm lub dial thiab cim nrog "Ω" ntawm ob sab. Tsis zoo li lwm cov kab, nws 0 txoj hauj lwm nyob rau sab xis, thiab cov nplai tsis sib npaug. Nws hloov ntawm sparse mus ntom los ntawm sab xis mus rau sab laug.
Qhov kawg kev ntsuas ntsuas tus nqi ntawm tus pointer multimeter yog: nyeem ntawm tus dial pointer * qhov ntau ntawm cov xaiv ntsuas ntsuas iav. Piv txwv li, yog tias qhov ntau ntawm qhov kev ntsuas qhov ntsuas qhov ntsuas tau xaiv yog "* 100" iav thiab tus pointer nyeem yog "20", ces qhov ntsuas qhov kawg yog 20 * 100n=2000 Ω.
2. DC / AC voltage scale: DC / AC voltage scale nyob rau ntawm kab thib ob ntawm lub dial, nrog "DC / AC" cov cim ntawm ob sab. Nws 0 txoj hauj lwm yog nyob rau sab laug, thiab lub teev yog sib npaug. Hauv qab kab lus no, muaj peb kab ntawm qhov ntsuas qhov tseem ceeb sib haum rau nws qhov ntsuas, uas tuaj yeem nyeem cov txiaj ntsig ntawm DC voltage thiab AC voltage.
Qhov kawg DC / AC ntsuas tus nqi ntawm tus pointer multimeter yog: kev nyeem ntawv ntawm tus dial pointer multiplied los ntawm cov xaiv iav ntau yam thiab qhov siab tshaj plaws tus nqi ntawm cov nplai kab uas tus dial pointer nyeem nyob rau lub sijhawm no. Piv txwv li, qhov ntsuas qhov ntsuas tau xaiv yog DC voltage "100", thiab tus taw tes nyeem ntawv yog qhov ntsuas "6" ntawm kev nyeem "0 ~ 10", yog li nws qhov kev nyeem ntawv kawg yog: 6 * (100/10) V=60V.
3. DC tam sim no nplai (A): Lub ntsuas DC tam sim no nyob rau ntawm kab thib peb ntawm lub xov tooj, nrog "DC A" cov cim ntawm ob sab. Nws txoj haujlwm 0 yog nyob rau sab laug, thiab qhov ntsuas tau sib npaug, uas tuaj yeem nyeem tus nqi ntawm DC tam sim no.
Qhov kawg DC tam sim no ntsuas tus nqi ntawm tus pointer multimeter yog ntau yam ntawm tus dial pointer nyeem x qhov xaiv iav ntau yam thiab tus nqi siab tshaj plaws ntawm qhov ntsuas qhov twg tus dial pointer nyeem nyob rau lub sijhawm no. Piv txwv li, yog tias qhov ntsuas qhov ntsuas tau xaiv yog DC tam sim no ntws "0.5mA" thiab qhov ntsuas ntsuas ntsuas yog qhov ntsuas "10" ntawm kev nyeem "0-50", nws qhov kev nyeem ntawv kawg yog: 10 * (0.5/50) mA=0.1mA.
4. Decibel dial (dB): Lub decibel dial yog nyob rau ntawm kab plaub ntawm lub dial, nrog "dB" cov cim ntawm ob sab. Tsis zoo li lwm cov kab, nws qhov ntau yog "-20 ~ +22", thiab cov nplai tsis sib npaug. Nws yog tsuas yog siv los ntsuas qhov nce lossis attenuation tus nqi ntawm amplifiers.
Yog tias qhov qis tshaj AC voltage siv thaum ntsuas, tus nqi dB tuaj yeem nyeem ncaj qha rau ntawm kab decibel; Yog tias siv lwm lub zog, kev nyeem ntawv yuav tsum tau ntxiv nrog ntxiv decibels. Yog hais tias lub load kuj tsis zoo ib yam li tus qauv kuj siv rau ntawm qhov teev, kev nyeem ntawv yuav tsum tau txais los ntawm kev hloov dua siab tshiab.
5. Transistor amplification factor scale (hFE): Lub transistor amplification factor nyob rau ntawm kab tsib nyob rau hauv qab ntawm lub teev, nrog rau "hFE" cov cim ntawm ob sab. Nws 0 txoj hauj lwm nyob rau sab laug, thiab lub teev tsis sib npaug. Qhov kawg ntsuas tus nqi yog qhov nyeem tau qhia los ntawm tus pointer.
