Why is the Probe Interface on My FNIRSI Multimeter a Tiny MCX Connector?

You might be wondering why your FNIRSI multimeter has a tiny MCX connector instead of standard probe jacks. This small port is key to the meter’s high-frequency measurement abilities. That tiny MCX connector is designed for clean signal transmission up to gigahertz frequencies. Standard banana jacks would create interference and signal loss that ruin RF … Read more

Why Does the FNIRSI Multimeter Not Include a Thermocouple for Temperature?

I bought an FNIRSI multimeter expecting it to measure temperature, but was surprised to find no thermocouple in the box. This missing accessory matters because temperature readings are crucial for electronics troubleshooting and HVAC work. The company likely cuts costs by omitting the thermocouple, knowing many users already own one. They also assume most buyers … Read more

Why Are There No User Replaceable Batteries in My FNIRSI Multimeter?

I opened my new FNIRSI multimeter and found a sealed battery compartment with no way to swap the cells myself. That frustrated me, because I expected a simple battery door like every other meter I have owned. The truth is modern sealed batteries allow for a thinner, waterproof case that protects sensitive electronics from dust … Read more

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