Things I like: 1) Uses BNC connectors for the DSO probes. 2) uses standard multimeter probes 3) great size for the functions it offers The bad: 1) The manual is terrible. It tells you what instead of how. e.g. This is the timebase, but no description on how to change it. 2) Inconsistency in DSO auto scaling functions. Sometimes it couldn't lock onto its own 3V square wave. 3) No probe compensation. Though it uses standard BNC probes, so you can easily get ones that have that. 4 The aligator clips on the signal generator are extremely difficult to use. Imagine loose plastic that is almost friction free and when you squeeze, the jaws twist so you are no longer able to open them. Absolute garbage on this. Change them out as soon as you get them. 5 FFT causes false display on the DSO and corrupts the data. I tried to get a FW update by visiting the site, but there is no FW to update. I actually gave this a 1 star review initially. It took a long time to work out how to use the timebase, as in how to adjust it. For those that are trying to actually press the timebase icon, just don't. It does nothing. To change the timebase you touch the screen either to the left or to the right of the middle vertical grid line. Touching to the left increases the timebase (makes the waveform compressed), touching to the right expands the waveform (reducing the timebase). Thats it. Hard to believe it took me over an hour and my wife another 30 minutes till we stumbled on it. We kept trying to press/double press, time the presses on the timebase key. Which goes to highlight the importance of a user manual. Had this been described in the manual it would have been easy. An onscreen prompt/help would have been nice too. Multimeter: Its as accurate as most people need. If you want better accuracy then you need to pay for calibrated high end equipment. This one was accurate to about 10mV in the Volts scale when measuring 5V DC. So 0.01Volts error. Same error measuring 30V DC. I don't ever measure current with a multimeter. It's a great way to hurt equipment or yourself... Continuity: Forget it. The delay is too long. I'm used to instant response like a Fluke or even most other meters. This one responds in about 2 seconds. My sample exceeded all the error specs in their table. Though, the best it can do according to the table is 0.5% and up to 5% depending on measurement. Good enough for most things. A few tweaks and this would be a very usable instrument. Make the continuity fast responding. Put frequency and amplitude bars on the FFT. I know this is a poor spectrum analyzer. Having those details turns FFT from useless gimmick into a rough analysis tool. While I'm at it, if you output 60Hz sine wave on the generator and feed it into the DSO, change the timebase to 200mS and the DSO displays a 100% AM signal. See the attached pic. That is a sinewave output shown as an AM modulated signal, which it is not! I suspect the FFT algorithm is interfering with the DSO function. That means it is pointless to use it. So right now, the FFT is not only useless, it will corrupt the DSO display. So just don't use it. Worse still, it then gives an incorrect FFT. The bottom line is would I use it in its current condition. The answer to that is no. It's got too many issues to use as a serious instrument. It does however have the potential to be a great tool, if they address the issues.

I'll admit, I'm not the biggest electronics guru; I'm a light hobbyist at most. However, I couldn't turn up the opportunity to get a proper oscilloscope. While this thing isn't anywhere near the monster of utility that something like an HP 16000C is, it's not bad at all. Actually, who am I kidding, for $140, it's pretty great. In the bag, you get two BNC probes for the oscilloscope portion, two banana jack probes for the multimeter portion, a third cable with two alligator clips for the function generator, and some colored rings to denote which probe is which. I kinda wish that the function generator were just another BNC jack, but I can understand why they wouldn't want to do that, which was probably to save on space. Speaking of space, this thing is tiny. It's about 6.5"x3.5"x1.25". It's definitely something that an electrician on the go could make space for. As far as its multimeter capabilities go, it covers all the standard bases: resistance, voltage, amperage, capacitence, diode testing, and of course AC voltage and current as well. I won't restate the ranges, as a kind individual has already posted all the pictures of the manual. I tested its multimeter capabilities by poking both my bench power supply and a USB charger, and comparing it against a Fluke multimeter I had on loan. Voltage was a bit higher than the Fluke's reading by 0.02V, and current was off by about 0.03A. Not bad at all. Resistance was pretty much spot on between the two devices, with most resistors I tested having the exact same resistance. It's a pretty solid multimeter at least. Function generation was one of the things I was most excited to try. It is limited to 3V maximum, which I imagine is partially due to it being a portable device, so I can take a concession on that one. If you really need more voltage, just use an opamp or something. It's all the standard waveforms you'd expect: sinusoidal, square, sawtooth, stuff like that. You can play around with the duty cycle as well for square waves. Sine waves can go from 1-10MHz, and other waveforms cap at 5MHz. I tested how clean the signal was by testing it both with another portable oscilloscope thing (a multimeter that had some oscilloscope functionality tacked on), and the actual device itself. Yes, this thing can multitask. From both (after pressing the very convenient Auto button), I got a nice, clean sine wave. The other waveforms I tested were just fine as well. Score two for it being a pretty decent portable signal generator. Now comes the big one: the oscilloscope functionality itself. Again, I'm no electric wizard, so I only know of so much to test. This thing can handle up to +/- 400V input, and can handle both AC and DC. I only tested with DC, as I didn't feel comfortable poking the outlet. This is a two channel device, so I decided to see how clean both my USB and bench power supplies were. Some ripple on the 10mV scale, less on the 20mV scale, and by 50mV, it was smooth. Again, I'd refer to the manual pictures for what all it could do; I couldn't for the life of me explain the utility of the Fast Fourier Transform when it comes to an oscilloscope, but it sure has it! My one gripe (and this is a similar gripe I have to my multimeter that also apprentices in oscilloscoping) is data logging. The only way you can really save data on a waveform is to save it as a screenshot. You can show plenty of values using the Measure menu, which is okay, but I'd really like for it to just dump data as a CSV or something like that. Something that you could pipe into Excel or something and really get some use out of the data being read. I can't help but feel like this would be easy to implement, especially if you were to put a microSD card slot on there (or even just dumping to internal storage). Screenshots are okay, but getting a proper dump of the waveform would open so, so, so many avenues as far as proper analysis goes. The auto functionality is great, though. When it came to testing waveforms against itself (and checking the cleanliness of my power supplies), it figured it out in a second or two at most. Unless you really know what you're doing, I'd suggest having that on at all times. "Funcation" is a really silly typo to miss out on, but it adds some character to it. All in all, I'm very happy with this device. It's got quite a lot of functionality to it for such a small, portable, battery powered device. Outside of the data logging issue, this does quite a lot. While I wouldn't suggest hauling it around without it being in a case or something, it's robust enough that it could handle some decent field work. The oscilloscope is sensitive enough to pick up some fairly minor perturbations, and has a lot of the standard functions that (apparently) the average oscilloscope has. The multimeter is about as accurate as a name brand. The function generation is nice and clean. If only it had some good data logging rather than just screenshotting...

The first thing I wanted to see on this was whether it could be a signal generator and an oscilloscope at the same time. It can! It can also be a multimeter and an oscilloscope at the same time. That is extremely useful. Way back when, that was several hundred pounds of equipment. This does default to Chinese, but it goes right to the language setting, and it's easy to switch to English. I didn't have to do a thing to actually set it up. I checked its accuracy with a wheatstone bridge, and it is quite accurate. It was accurate within .001 ohms. Not bad. The probes are high quality and accurate. They have a 10x switch on them. Standard BNC, so you can use them on whatever. The ground leads swivel. That should be far more reliable than soldered leads. I'm used to the old school oscilloscope, so this thing is absolutely tiny to me. It's fatter than a cell phone, but nothing compared to the old stuff. The screen is nice and legible. The screen cover is still there. It works fine with the protector on there, so it's staying there. It's worth the money for sure. I spent a lot more than this on old school oscilloscopes that can't do 1/10th of what this does. The only problem is the instructions aren't great. They aren't the most terrible I've seen. You can get what need out of them, eventually.

This could definitely be a 5 star tool with a good firmware update that improves the user interface. What it can do in such a small size is amazing. I don't want to be too hard on the team that programmed it. The fact that so many different functions work at all was a huge task. I hope they take on the next task, refinement. Misspelling hard buttons (FUNCATION) is an unforgivable oversight. But the tool still works. I'll chose to believe that I have a rare early edition error that will only become more valuable as this tool becomes the new go to form factor. Hey, it could happen. I checked this against a Rigol DS1052E which is a low end 50Mhz scope from a decade ago. The wave forms actually look better on this screen. More smaller pixels on roughly the same size display. If you are a complete noob, the FNRSI is probably easier to figure out how to get a first scope measurement. That is quite a feat given the Rigol has 24 buttons and 6 knobs, 25 silkscreened legends and 5 buttons with on screen legends. The FNRSI has 5 buttons with legends including the power button, and a touchscreen. The Rigol is easier to get real work done. Because, knobs. A small touchscreen for everything results in many accidental touches, loss of work. Sometimes a lot of work, for a single errant touch. Some important features have touch boxes much smaller than my finger. So I try over and over to hit the right one, finally got it. Run Oops, changed mode to multimeter instead. Start over from the beginning. That will have you hating this interface in a short while. Each tool does not need to have its own screen mode. The probes(2 scope, 2 multimeter, 1 signal generator) can all be plugged in at the same time, they should all be usable at the same time. That would make this a useful tool. Right now it is a frustrating toy. Hopefully that is something that can be added with firmware, but I suspect that they put the switch in hardware and are reusing peripheral to make this trick work. Some of the largest touch elements on screen are the run/pause indicator, even though that function has a dedicated hard button. And that indicator stays on screen even in modes that dont use it. Just dumb. But it will get better. I hope.

I have some other FNIRSI equipment and have always been pleased. The output is accurate enough to be actionable, and goes a good way in helping me learn where I really need extra protections and filtering. As an example, I was able to use this to monitor transient spikes from HVAC relays I've been working on, to see if I actually need a flyback diode given the transistor I used; it had no problem seeing the spikes and showing them to me. The measurements I get from this device are in line with other tools I use, which I think's pretty excellent for its feature set and price. The device is more precise and at least as accurate as the handheld multimeter I've been using for decades, and is likely to replace it (particularly because I'm not a fan of replacing alkaline batteries). I was surprised to find the "auto" mode so helpful and generally able to quickly put me in the view/scale I wanted. The touchscreen is also decent at picking up where I pressed and I found it to be very usable; it's much improved over previous FNIRSI units I've tried with tiny buttons which handle many different roles. The closest I can come to a real complaint is I wish the DDS/generator could handle up to 5V output rather than being limited to 3V.

This FNIRSI 2C53P Plus is an incredible value, packing three essential tools into one compact device. The oscilloscope offers a respectable 50MHz bandwidth and 250MS/s sample rate, which is more than enough for most hobbyist projects. The multimeter is accurate and reliable, and the built-in DDS signal generator is a handy bonus for testing circuits and components. The 4.3-inch touchscreen interface is intuitive and easy to use, making navigation and control a breeze. I'm incredibly impressed with the functionality and performance of this device, and I highly recommend it to anyone who enjoys working with electronics!

Overall this is pretty dang cool. The multimeter functions surprisingly well, and the oscilloscope and signal generator are okay. I honestly find FNIRSI's 1013D touchscreen oscilloscope to be a bit more intuitive and definitely more feature reach (as a scope) for a similar price. I'd argue this is well suited for someone who wants the basic functionality of these three tools in a highly compact form factor. FNIRSI get's bonus points from me on this unit though for making the cutouts around the BNC connectors large enough to accommodate standard insulated oscilloscope probes from other manufacturers. For folks looking for a deep dive before they buy I'd highly recommend checking TechCornerTV's YouTube channel. He covers a lot of the nitty-gritty in much better detail and with much better expertise than I can.

Wow, this is an impressive scope for the money! Oscilloscope 2 Channel 50MHz Bandwidth 250Ms/S Counts with a 4.3 Inch display. What's not to like? This oscilloscope performs better than my old digital Fluke oscilloscope that cost 15 times this price 25 years ago. Not only is it two channels at 50 MHz bandwidth, but you can also do basic math functions with the waveforms. So you can do a Lissajous pattern between X and Y axis to see the phasing outputs. It also outputs a myriad of details of the waveforms from voltage and frequencies to peak and RMS and other items too. It has a touch screen display and is very intuitive for operating it. It also has a built in multimeter mode that is quite versatile, and also has a built in DDS function waveform generator that can output 12 kinds of waveforms up to 10MHz, with a step of 1Hz. The display is super easy to view, and in color too. You can save the waveforms. This is an amazing scope for the price point. Having two channels and the math functions is key for me. All at an excellent price point.

When I was still doing commercial & public safety radio I would lug out a heavy service monitor to check a customers radio before bringing it to my bench. This scope/multimeter easily replaces a 40 pound cart mounted instrument. The scope function is very customizable. Likely it will do almost everything you need in the field. Won't replace your expensive bench scopes though. With the volt meter I can check blown fuses and corroded butt splices. The scope allows me to see if audio is getting to a speaker, and the ohm meter lets me test the speaker and wiring. The signal source functions are wonderfully customizable and quite useful. There are more options than I'd likely ever use. Included voltage probes and scope probes are very nice, better than expected for this price range. A few issues: The scope doesn't seem to show anything until there is a minimum voltage present. Anything less than about 2% of full screen doesn't trigger the scope. Just go to a lower range. Also I wish the graticule top and bottom were full size. They are compressed a bit, but you can deal with it. Dragging the scope 0 volt line is a bit of a pain with the touch screen, but do able. The Fourier analysis function of the scope is very useful. But setting the time base requires a precise touch. Kinda tricky. You need to press the Gear label to manually select modes using the multimeter. It can be hard to press in just the right place. It might take some practice. The FUNCATION label is good for a laugh. Using the voltmeter - I placed the voltage probes across a lithium battery. The voltage showed 3.2v (expected). When I put my fingers across the battery terminals to hold the probes on, the voltage display jumped around like crazy giving a bad reading. Odd. All in all, not a perfect instrument, but more than good enough. Won't replace your bench instruments, but good for field use. I really like this.

I have tested like 5 other handheld multi scopes and now including this one When first receiving this, I allowed the unit to get fully charged using the USB cable this comes with but you must supply a USB charger. It is odd though that when charging devices it is best to do it when the unit is turned off, and it has some visual way to know if the internal battery is still charging or is fully charged. This product has none, so you have no way of knowing to take it off the charger or not the lettering for all the ports and connectors are the same black color of the case, so be sure you're connecting to the function you're going to connect a voltage or frequency to Next is I went onto the website for the maker of this and found there was already a newer firmware version so I downloaded the update and copied that to a folder on the unit and after rebooting it the newest version was showing being used The user's manual is only about 20% content in English. It really needs to be rewritten and more content on how to use. It tends to use English words that make little sense, like keep's mentioning "Gears" which really is functions The manual is only about the size of a hand and the fonts are small, be better if both are larger Good coloring on the screen but no adjustments for contrast Using 2 other handheld multi scope brands to use as a compare to this one, I tested 1. Using an adjustable D/C power supply with the unit in meter mode went from 0 to stepping up to 30 volts, the unit was correct each time 2. Plugging into a 120 volt A/C socket, meter read correctly 3. Using different resistance value resistors, unit read the Ohms correctly 4. Using a signal generator, test both single and both channels in scope mode with different frequencies 5. went to signal generator mode and had 2 other scopes attached to assure this function worked correctly 6. tested the temperature function, was fine Overall testing showed all functions worked just fine so due to its larger screen size for a handheld should be a useful test tool, even when debugging problems with vehicles