SMT-51A 是一款由上海四達(dá)電子生產(chǎn)的袖珍型指針萬(wàn)用表，具有便攜性和多功能性，適合職業(yè)培訓(xùn)、專業(yè)學(xué)生、家庭用戶、業(yè)余愛(ài)好者以及專業(yè)人士使用。該萬(wàn)用表采用雙注射工藝，外殼堅(jiān)固耐用，能夠有效保護(hù)內(nèi)部元件，確保測(cè)量的準(zhǔn)確性和穩(wěn)定性。

SMT-51A 可以測(cè)量直流電壓、交流電壓、直流電流、電阻等多種參數(shù)。直流電壓的量程包括 10V、50V、250V 和 500V，精度為 ±4% 滿度值；交流電壓的量程與直流電壓相同，但精度為 ±5% 滿度值。此外，該萬(wàn)用表還具備電池測(cè)試功能，可測(cè)試 1.5V 和 9V 的電池。

SMT-51A 的設(shè)計(jì)注重用戶體驗(yàn)，配備了導(dǎo)通性測(cè)試功能，當(dāng)電路導(dǎo)通時(shí)會(huì)發(fā)出蜂鳴聲，方便用戶快速判斷電路連接是否正常。此外，它還支持頻率響應(yīng)測(cè)試，可測(cè)量 50Hz 和 60Hz 的頻率。

該萬(wàn)用表的體積小巧，尺寸為 100×69×32mm，凈重僅 116g，便于攜帶和操作。它使用 AA 1.5V×1 電池供電，配備測(cè)試引線、使用手冊(cè)和包裝卡等附件。

The SMT-51A is a pocket-sized analog multimeter produced by Shanghai Sida Electronics. It is designed for vocational training, professional students, home users, hobbyists, and professionals. With a double-injection molded case, the SMT-51A is robust and durable, ensuring accurate and stable measurements.

The SMT-51A can measure a variety of parameters, including DC voltage, AC voltage, DC current, and resistance. The DC voltage ranges are 10V, 50V, 250V, and 500V, with an accuracy of ±4% of full scale. The AC voltage ranges are the same as those for DC voltage but with an accuracy of ±5% of full scale. Additionally, the multimeter features a battery test function for 1.5V and 9V batteries.

Designed with user experience in mind, the SMT-51A includes a continuity test function that emits an audible beep when the circuit is complete, allowing users to quickly determine if the circuit connections are intact. It also supports frequency response testing for 50Hz and 60Hz.

The compact design of the SMT-51A, with dimensions of 100×69×32mm and a net weight of 116g, makes it easy to carry and operate. It is powered by a single AA 1.5V battery and comes with test leads, a user manual, and a blister card.