[LearnElectronics] grabbed a FNIRSI tablet oscilloscope from a vendor from China. The device has a seven-inch touchscreen and claims to be a two-channel 100 MHz scope. But is it? Watch the video below and you’ll see.
Spoiler alert: [LearnElectronics] was skeptical of the 100 MHz claim and it looks like it is more like a 30 MHz analog bandwidth. Despite that, it does seem like a pretty capable 30 MHz scope in a very handy form factor and a very cheap price: as little as $120 or so, depending on where you shop.
The test setup was a bunch of can oscillators and up to about 30 MHz, the scope did OK. After that, the results were less than stellar. However, we aren’t sure that the test setup — on a solderless breadboard — wasn’t part of the problem and we’d have liked to see the test done with some known good quality probes as that can also contribute to bad readings even if the scope’s circuitry is up to par. We’ve seen reviews of these cheap probes that suggest they aren’t bad, but they aren’t actually all they claim, either.
The verdict? [LearnElectronics] likes it for a 30 MHz cheap scope. Of course, cheap is a relative term here. You can get a much better scope, but it will probably cost more than this one. For most of what you are probably doing with a scope, this seems like it would be adequate. On the other hand, throw in a few hundred extra dollars and you could have more channels, a more likely chance of measuring high-frequency signals, and probably enhanced measurement capabilities, too.
We will admit, though, having a portable battery-operated scope can be super handy sometimes, and you don’t always need the highest speed. You probably use your cheap multimeter more than your six and a half digit bench scope, too, right?