Why Does My FNIRSI Multimeter Not Support 28V from PD3.1?

The FNIRSI multimeter you own likely cannot measure 28V from PD3.1 chargers because its hardware is designed for older USB Power Delivery standards. This is a common frustration for people trying to test new fast-charging laptops or power banks. PD3.1 introduced a new 28V fixed voltage, which requires specialized circuitry to negotiate and measure safely. … Read more

Why is the 9999 Ticks RMS on My FNIRSI Multimeter a Lie?

You bought an FNIRSI multimeter that claims 9999 counts for True RMS readings. But the numbers you see on the screen do not match real-world tests. This matters because you rely on your meter for accurate work. The 9999 ticks promise is misleading because the internal ADC chip only has 6000 counts of genuine resolution. … Read more

Why Does My FNIRSI Multimeter Display 11.9 Vp-P for a 10 Vp-P Sine Wave?

You see your FNIRSI multimeter showing 11.9 Vp-p when you know your sine wave should be 10 Vp-p. This difference can confuse you and make you question your equipment’s accuracy. This reading is important for getting reliable measurements in your projects. Your meter likely measures peak-to-peak voltage differently than you expect. Many multimeters, including some … Read more

Why Would My FNIRSI Multimeter Not Hold up in Professional Use?

I bought my FNIRSI multimeter hoping it would save money over a Fluke. It worked fine at home, but in a professional shop, it started acting flaky. The plastic housing cracked from a small drop, and the readings drifted. A professional meter needs to survive daily abuse, and my FNIRSI just was not built for … Read more

Why Does My FNIRSI Multimeter Only Have Coarse Timebase Adjustment?

When you notice your FNIRSI multimeter only offers coarse timebase adjustment, it can feel limiting. Why this design choice exists helps you use your meter more effectively for basic frequency measurements. Many budget-friendly multimeters, including some FNIRSI models, prioritize simplicity and cost over fine control. A coarse adjustment is often sufficient for checking if a … Read more

FNIRSI DSO-TC3 vs FNIRSI DSO152: Best Oscilloscope & Transistor Tester for DIY Electronics?

FNIRSI DSO-TC3 vs FNIRSI DSO152: Best Oscilloscope & Transistor Tester for DIY Electronics? I’ve been testing two popular FNIRSI handhelds side-by-side: the DSO-TC3, which packs an oscilloscope, signal generator, and transistor tester into one box, and the simpler DSO152, a dedicated 200kHz bandwidth pocket scope. The DSO-TC3 boasts a 500kHz bandwidth and 10MSa/s sampling rate, … Read more