EEVblog #1007 - Is a $25 Multimeter Any Good?

hi we're going to do something a bit different today and probably something you wouldn't think you'd see on the EEV log and that's a review of a cheap-ass multimeter this is the aiming an8 a double o8 multimeter and it sells for 25 US dollars delivered from the aiming store on Aliexpress which is where I got it from it's the official one you can buy from other stores or you can even buy it cheaper maybe around $20 or maybe even under that delivered and there was a bit of talk about this on the EEV vlog it is in you not a model don't confuse it with the in8 double-o - they've got different models this is like the upgrade the new upgraded more expensive version and why would I take a look at this well I thought it might be interesting because it's got a couple of low-level modes which are useful for electronics and of course you know let's have a look okay a lot of people say they have a bias against cheapest multimeters and yes I do I don't like cheapest multimeters but I do know that they have their place you want to you know you don't want to work on main stuff you just want to work on some breadboard stuff and and you know buying a twenty twenty five dollar multimeter okay you know it's probably going to do the job so let's have a look at see what you get now the first thing is that it's actually a 10,000 count meter 9999 which is better than your usual you know five or 6,000 count multimeters on the market you actually get the extra digit if you're measuring say seven volts for example then you got to get seven point zero zero zero instead of going up a range and getting seven point zero zero you're going to get that extra digit of resolution so right there it's handy now they're going to claim that at 600 volt cap three thousand volt cat - absolute rubbish of course you know don't like these cheap-ass multimeters not independently tested at all you wouldn't trust of any further that you can throw on four main juice I don't recommend you you know test mains with these or any other high energy high voltage stuff but the simple you know hobbyist breadboard low voltage type work it's it could do the business now you actually get a fair few accessories for your twenty a bus to live it you get your regular our probes with the shrouds on they're not that you need bloody those things they're really annoying reasonably well they're actually quite sharp and they actually got decent finger guards on there and they're okay they're only rated cat to 600-volt 10m if you believe that you know take it with a grain of salt but they do know the actual probe is compact enough it's it's reasonably nice these are not our silicon leads of course they're just regular PVCs but they feel and I'm reasonably decent not going to cut one open to see how much coppers in the thing but you also get these ones as well so you can't look these little plug in ones which are you can get all these accessories spade lugs and things like that handy probes and in four millimeter banana jacks to go into there and a bunch of alligator clips and a bunch of screw on protip suit quite handy for the money little manual and look at the pouch look at the pouch got to be worth it just for that gorgeous pouch and out of the box it doesn't look like there's a better in there or it's completely dead well now the first thing you notice about this thing is it's absolutely tiny it's almost pocket like if we compare it to the be m23 five which is already a small compact multimeter you can see that the physical difference in there in fact they obviously design this thing to match the size exactly to the fluke 101 and there are photos oh oh oh edit in a photo there but yeah they are identical sizes are width height and thickness apparently to the Fluke 101 but it's open it's not a direct competitor but they just copied the form factor and the tilting bail well it's you know pretty crusty you it's like like there's just no heft in this thing it's so light that you know you really have to sort of put a force down onto that to use it and if you can't even press the buttons with the dam like forget we don't turn it off before we take it apart so do a quick a teardown little self tappers in the thing and it you can actually replace the two double A batteries didn't come with it without taking out the screws but and that does have a metal threaded insert for that which is nice but if you want to replace the fuses because both ranges are fused apparently yeah you got to take up a self-tapping so let's can we open it's probably got a clip in there somewhere and we're in like Flynn and that's exactly what you expect in a cheap-ass multimeter like this where like the contacts are just yeah the not even the solid ones just that like the pressed spring metal going over and you know pretty terrible 10 amp con shop but interestingly look at the fuses yeah both ages of users fuse and yes they are HRC high rupture capacity fuses in quote marks but they're absolutely tiny so that's a 10 amp job at 250 volts and on this high-voltage rubbish and 200 milliamps down here for the combined volts end milliamp micro amp jack down there so yeah so right off the bat I can't see any protection in here apart from the fuses where are the PTC s where are the mobs they're just not there nice little arm elf resistors there you know I'm a MILF resistor fanboy but unless the protection devices are on the bottom side what do we have over here we've got one there it is PTC right up there on the other side of the battery contact right near the chip so that's a interesting that placement so yeah like two bare minimum input protection there's a fuse where do you even find those they're 10 millimeters by 3 millimeters by the looks of it ah geez like why in 205 at least thank you so the lack of any input protection like moles and we've got a single PTC but there's no like diet looks like unless it's on the bottom there's no do protection for the amps important stuff like that like I just this is why I do not recommend these for anything probing around on the mains or other high energy high voltage circuits just don't and we've just got our chip on board blob there I believe it's a high contact chipset then we've got our a squared prom next to that which holds the calibration and other setup varies you might actually I think some people on the forum been talking about maybe changing some register settings and stuff like that because it's external you could actually modify that and play around with it but you know very interesting levers a PCB context switch here I wonder what that one does hmm and there's a voltage reference there tío 92 packages it looks like a genuine inter-cell genuine in quote marks it could be anyway it's an IC l8er 69 it's the DC Zed R which is 100 ppm version there is a 50 ppm version so you know it didn't add adequate for a 10,000 count multimeter interestingly they got the silkscreen wrong they say ICL 1896 instead of 1869 oops and the soldering qualities you know man it's what you expected it's window Lomita it's fine well hello solder joints for your 10 mm current shunt you saw the joints via fuses they're all manually done of course they look dry as a bone daily Wow that but apart from that and that's exactly what you'd expect on the top and then no there were no additional wire components underneath for our protection area you know I bet pretty typical why I arranged switch implementation and as for the contacts down in there yep all pretty standard fare they switch it on and first thing you notice it's a nice high contrast large digital really like them you know like you can compare glare and stuff until the cows come home it is a little bit Larry with its a curved top on it and stuff well I can probably you know get it to like yeah anyway it's a pretty good screen I like it and I like the big crisp high contrast digits they're really quite nice they're real it's really good at most angles so yeah big thumbs up for the screen that's for sure now the first thing you should have noticed is that look 10 micro volts a resolution here on the 100 million range because it's a you know ten thousand count so you might think that's and that is really good right that's better than most meters already but this thing has another one up its sleeve put in manual range look it's got a 10 millivolt mode with one that millivolt resolution it's overloading because it's you know just getting noise on the input let's give it a bill this is awesome so use my MV 106 our transfer standard here 10 millivolt range and even my seven-and-a-half digit keysight only gives us one that digit better than this look and it's bang on basically 1 millivolt 1 microvolt resolution this is great if you measuring our tiny voltage drops across current shunt resistors or something like that brilliant whatever meter let alone a you know a $25 meter has a 1 microvolt resolution that's crazy and it's pretty close to being on in the upper range there too and that's 90 millivolts and 10 millivolts being on and it's bang on it's 10 millivolts on the 1 volt range because it's 9999 count it's like it's great I love the high account meters it can be a bit initially confusing if you used to the regular ones but there you go it's pretty quite like plus it's it's bang on there's 9 volts not too far off at all that's on the 10 volt range go down to 1 volt bang on nice 90 volts there's only a couple of least significant digits off and well let's go up two three four five six hundred volts 700 volts 800 900 988 there you go so that's yeah that's pretty close to what a couple of least significant digits there and we'll just flip that voltage around negative there you go don't like the extra rows zero out there on the key side that's a bit how you doing hmm anyway let's bang on to the keysight 7f digit meter and i've checked the inverse on other ranges too and it's basically like one least significant digit on the negative and on my AC voltage standard here let's have a look at AC because AC can do the 1 microvolt resolution to true RMS in quote marks it's not going to be high bandwidth just like one or two kilohertz or something like that depend on the chipset 1 microvolt ac true RMS resolution look at that it matches my seven and a half inch digit keysight that's just crazy it's pretty much bang on dude that's it one kilohertz by the way a true RMS in quote marks these things you know only going to do a couple of kilohertz but at 1 kilohertz bang on and a 400 Hertz to the 1 volt range at 1 kilohertz we're talking 30 counts out but me what's that in percentage and that looks to be a frequency dependent thing because it's only 10 nine or 10 counts are different at 400 Hertz so that's on exactly the same voltage yes so it you know it's starting to taper off at a kilohertz well taper off wasn't the right word if it's starting again but that's common they can like have a big lumpy gain at the end and then roll-off no in volts 400 Hertz 9 volts 1 kilohertz is bang-on 90 volts 400 Hertz and 600 volts 400 Hertz 700 volts are the keysight might our poor little keysight's not going to yeah overload there you go way and overload on that twos I can't do a thousand volts I can't do up to a thousand volts AC but it's 700 volts no are you swimming oh I couldn't off on the resistance but it's ranged up there yeah near enough oh yeah it's doing the business good enough it's hanging in there not too shabby on the 10 Meg range unfortunately that is the best it can do it can only go to 10 Meg it can't go any higher it might be a little bit annoying but I'll give it a pass and if I have a look at the basic specs here exactly where you expect from such a meter to your typical half percent in our fuel II significant division digits one percent on the AC true RMS and stuff like that DC current point eight you know it's like you're not going to write home about it but that's what you get for 20 bucks it's fine and just for completeness there's the rest of the specs three times the second screen updating or the rest of the stuff as for the manual man you know it takes what you expect for a twenty dollar multimeter it's all in English and I won't get your measure of the accuracy of the capacitance Ranger couldn't be bothered but the good thing about it is that it's got one tough resolution on the thing and if you disconnect it it actually gives you a true zero result because there is no relative function so that's a one disadvantage of this meter which is I would have been really great if it had that but yeah like it zeros out a lot of meters don't do that very nice and I'd use my reference capacitor on this thing but I lost it in the middle of a lab cleanup dull you cannot manual range on the capacitance range though just it's just completely disabled why continuity tester can get it to occasionally skip but that's pretty good it's latched and it's pretty quick let's pass and diode test mode you are limited by the two double-a battery voltage because I've got brand-new batteries in there we're getting three point two eight but that will change as your battery voltage drops but that's going to be good enough for a white LED sweet feel that that can give out our one point six odd milliamps yeah good enough to light the LED and one rather interesting mode is this digital out and look you selected 50 Hertz hundred two hundred and there it is there I mean it's okay it's our three volts peak-to-peak and obviously they're getting that from the regulator because the battery is like 3.2 but it goes up in light well once he jumps from 101 kilohertz to 2 but before that there you go I mean I I don't know but you like someone might find a world there we go but to go up to folk healer someone might find a use for that you know it's got a frequency counter seems to be a bit off I mean that's supposed to be 10 megahertz you know half a volt but it's not doing it so but it's but below that no problems whatsoever I mean 65 2.6 Meg here you go bang on just it though well there we go sorry at the higher frequencies it's not terrific but up to a couple of Meg it's fine and dandy it seems to need about a hundred and 50 millivolts i peak to peak to get anything actually it just seemed to be the lower amplitude that was a problem there at a higher amplitude eight point five volts peak-to-peak yeah it's bang on it almost the full 10 Meg range not too shabby on the one milliamp range look at that this had me stumped for a few seconds look at this generating nine milliamps and I feel like I just go to the milliamp range it's only four is the voltage jacks under shared with the micro amp range and so it gives you just some crap value there on the input I there we go yeah we talk and hang on oops there we go that's not great is it now check it out on the micro amp range okay hundred micro amp range at 10 nano amp resolution fan-freaking-tastic once again a great meter for like you know a low value a precision electronics stuff well when I say precision I don't mean accurate you know like in any way it can go down to relatively low currents but look the ranges that we've got okay so we've got a hundred micro amps and then we've got one a thousand micro amps which is one milliamp but then if we go over to our milliamp range here so our highest was one so we had a one milliamp range but where is our 10 milli ampere Ange we've only got a thousand so we don't know 10 milliamps or a hundred milliamps we've only got like a Saturn now we've only got the one amp or would it like it no sure enough if you go to the manual there's the fine print there's the two micro amp ranges a thousand one hundred micro amps and a thousand migrants but then it jumps up to one hundred milliamps so you miss your 10 milli amp and 100 milliamp ranges like their God that's practically a shows and look it's probably going to be accurate enough but like I like it's getting to the point where I'm not going to bother to generate the higher currents have to get other gear and like in yeah I don't forget about the backlight for all you backlight fanboys there you go not too shabby at all so it works alright one thing with this like auto if you go into manual range like that then I'm not sure how you actually get like back to auto without switching on the thing and it like I did like you've got to change ranges or whatever now that's fine actually I can't work that back one and I just measured the battery current around about 1.7 million on there so you can do the calculations for two doublea's to get your battery life shouldn't it's going to be okay so there you have it that's the aining if I'm pronouncing it correctly let me know if I'm not a n8 a w8 I can go into more detail and measure the true RMS bandwidth and measure all sorts of stuff but you know because that's enough for a little more than enough for a little 25 or you know sub $25 meter and well it's not too bad it's got some useful ranges on here it's you know it's going to survive a few knocks and things like that and for the price I mean you get all the accessories and stuff with it the leads may not be the best quality or whatnot and the input protection don't go use this on mines or other high energy circuits but for sub $25 multimeter I love some of the low ranges on this thing it really is quite neat seems to you know it astly exceeds its accuracy specs at least the one-off unit I've got here it could vary but that you know has got a half reasonable little reference in there the build quality is okay but you know I like it's as good as you can expect if you're after $25 moly meter you can do worse than this little thing I suspect anyway hope you enjoyed that look at a 25 buck multimeter it is what it is okay you could say that excellent meter for its 25 bucks there I said it but the lack of the current ranges is terrible those you know Russ you're real sweet spot stuff where you want that that's almost a showstopper I love the 10,000 count but geez the missing current range is there what is it 10 milliamps and 100 milliamps oh my goodness what is the water oversight what have they done that crazy anyway hope you liked that video and you know I'm not necessarily I think about all 25 dollar multimeters a crap it is what it is that you get more than more value than your 25 bucks in this thing it really is you know it is serve you quite well it's rather cute fun little meter anyway I'm not going to give it like a thumbs up or anything I can't bring myself to do that for $25 multimeter but you know for 25 bucks it probably beats probably most other ones on the market I don't know especially for instil compact size it's cute anyway if you liked the video give the video a big thumbs up as always discuss it eevblog forum down below all the comments catch you next time you

Channel: EEVblog

Views: 324,437

Keywords: eevblog, video, aneng, an8008, an8002, multimeter, review, teardown, voltage, current, resistance

Id: xdGQEVdxmQQ

Length: 21min 21sec (1281 seconds)

Published: Fri Jul 14 2017