EEVblog 1597 - Zoyi ZT-703S $80 2CH 50MHz Oscilloscope/Multimeter Review
ฝัง
- เผยแพร่เมื่อ 9 พ.ค. 2024
- Looking at the new $80 Zoyi/Zotech ZT703S Dual channel 50MHz 25,000 count 0.05% handheld oscilloscope/multimeter compared to the single channel 10MHz 10,000 count ZT702S
s.click.aliexpress.com/e/_DeS...
ZT-702S review: • EEVblog 1540 - The $80...
Forum: www.eevblog.com/forum/blog/ee...
00:00 - The new $80 ZT-703S vs the $60 ZT-702S
03:40 - Power on and screen differences
06:25 - Multimeter
07:49 - The Bargraph is still a complete JOKE
08:50 - Power-off memory test
09:41 - Dumb Arse Dave BRICKS the ZT-702S !
10:23 - The SAME current measurement FAIL
12:19 - 0.05% ?
13:17 - Same BNC connector issue
13:44 - The signal generator is still a joke
15:53 - Trigger level issue FIXED
16:39 - Range overload bug FIXED
19:10 - Teardown
25:07 - Oops...
25:21 - Battery life and current consumption test
26:54 - Conclusion
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#ElectronicsCreators #Review #Oscilloscope - วิทยาศาสตร์และเทคโนโลยี
If you buy the kit that includes two probes, they ship it with the second probe taped to the box containing the scope and wrapped in a mountain of bubble wrap. Unwrap it carefully and don't just cut the wrap off like I did, or you'll end up with a single probe kit plus 6 pieces of scope probe cable.
They need a college football player majoring in 'packaging engineering' to solve this problem.
Use a machete to open the package?
@@_BangDroid_ that's not a noife
@@_BangDroid_ thats not a knife! 🤣
lol
Well, I've seen Dave get excited over an oscilloscope AND seen an oscilloscope get excited by Dave all in one video now! Haha!
A guy I met on a flight, saw some of the videos I watch and recommended your channel. I wish I could find that guy. He knew me better than half my close friends.
If he recommended the channel, you probably will find him if you put the same comment in all the videos until he sees it. :) People will probably vote you up haha. Maybe Dave notices it and mentions you in a video or the amp hour haha
Is your name Ron?
@@Dont_Gnaw_on_the_Kitty No. Josh and a big guy that needed more arm room.
I can see a good use in the automotive field. Having a battery operated scope with live feed and trigger save can be a blessing for catching intermittent problems. Intermittent problems are the worst!
I totally agree with you. A device like that can be quite useful for any kind of test or repair which can't be done in the lab. Being able to see waveforms is great for debugging complex problems, but sometimes using a normal oscilloscope is just not possible
Came here to say that, if there was only a bit more rugged version it would be perfect
I do not know they survive that. I have seen a lot fried Fluke scopemeters used automotive. And those are pretty well protected. On the other hand, you can fry 50 of these against one Fluke. If you buy them 10 at one time you could probably get a discount.
@@xani666 Being able to save waveforms to an SD card would also be great (I haven't finished the video yet, so maybe it actually can)
@@pa4tim I do not think this one would fry more often but I do think it would do far worse on dropping and other mechanical abuse.
Maybe the mechanics try to probe the high voltage part of ignition lmao
love it man.. you cover the entry level stuff with just as much detail and insight as you do the high end gear. thanks
He never used to, KeepOnTesting made him think twice about calling CHEAP-O's crap. Muhahaha 😅
Oh man, I don't need this, but I want one so bad.
The bargraph is useful when you are watching to see if the reading is moving up or down. Visually seeing a meter needle move in a direction is easier than remembering and comparing numbers in your head. The needle also shows the rate of change. Quite useful.
I really like how you present these products. Great work 👏
one of the best things that i learned about these handheld scopes is that they are isolated from ground.... that makes them really useful for analysing signals in machinery where you dont neccesary know if the pin is safe to be grounded or where you need a relative measurement.
ive blown a couple breakers by accidentially hooking up the scope ground to a port that was not happy about getting grounded through the earth of the scope.
Interesting review. Nice to get these from you.
Though possibly getting upset about the 10A/mA issue is being a bit picky.
I won't be upgrading. The 702 suits me fine for measuring all that I do. 10MHz is good for checking power supplies, analog, and switching. Audio circuits. The analog multimeter is great for tuning rf and if circuits. The meter is accurate for most uses. Thanks for the review of the 703.
Dave, I've been watching your channel for a number of years, and I just have to say that I absolutely love your content. I am far removed from the field you're in, and I originally watched your videos sheerly out of amazement in regard to the knowledge you have with electronics (which of course makes perfect sense given your background lols). Pretty much every word that came out your mouth went in one ear and out the other, but your charisma makes it worth following videos through just to see what kind of crazy thing you end up tearing into next lol.
I have learned so many incredible things through your channel, like so many things, and I can't thank you enough! You're inspirational in your willingness to share your knowledge! I am not and likely will never be an electrical engineer, but damn do you ever make me wish I even knew the basics of the industry when I was in school, because I'd for sure have jumped into it headfirst haha!
You rock good sir!
Dave, you may have been a little harsh in your evaluation of the Zoyi ZT-703S with regard to its stated 50MHz bandwidth. The scope comes shipped with the bandwidth setting (shown under the menu setting “Run Mode”) set to “Normal Mode”, which limits the bandwidth to a maximum of 30MHz. This is done to lower power consumption. To measure signals up to the 50MHz maximum, you need to change this setting to “High-Speed Mode”, although it states the power consumption will increase. I would like to see you re-evaluate this scope with the setting on High-Speed Mode and see if it does reach its full 50MHz bandwidth and maybe check the power consumption in this High-Speed Mode compared to Normal Mode and let us know how it compares. Thanks!
Imo it should show "30kHz mode" for a brief second then, so people know there's another mode. I wouldn't know either.
This, exactly this. Although to be fair, if I used this, I wouldn't know better either. Hidden modes like this are why we read the manual.
Be honest though, the first thing we do is throw it out for simple use gadgets like this one, oh well I guess the 50MHz mode is hidden.
I remove the user manual, read it thru, then remove the device, check it to make sure they agree.
Nothing broken, missing, etc.
I can't imagine doing any other way.
All tools require inspection and familiarization, for safety, and best-bang-for-bucks.
If you don't your a fool.
@@snakezdewiggle6084 Sometimes I download the manual before I actually buy or before it arrives and read it through to know all about the device's features and test them immediately when my purchase is my hands.
I got one to review too, will be publishing it today, had to split into two videos, with second part being published later… I ended up with 2 hours of footage !
Would be a good cure for insomnia.
Been put off buying it now after this review. I will wait. Thanks for your input.
Dave, I bought a 702 a few months ago and the unit delivered has a defective probe. The switch would not select x1 ... x10. Amazon sent me a new scope and didn't require me to return the original one. So I bought a new probe and now have 2 scopes. ..... Lucky Me!
Dave, you should look at your own forum - there's a thread where we've done a bunch of testing, and identified a bunch of issues already. There are some new firmware versions available, but not all of the known bugs are fixed yet
So the output mode works at the same time the oscilloscope does, but the "other apps, gen" one only works as a standalone generator - you can't use the scope at the same time. In the "output" one that works with the oscilloscope, the regular square wave is fixed at 1khz for the probe calibration. There's a different square wave mode that allows you to change the frequency and the duty cycle. BUT the limitation is if you have the "output" on, it limits the timebases (and sampling rates) available in oscilloscope mode. Took quite a while to figure out that limitation, though it is mentioned in the manual.
That was for the 702S. I didn't see another one for the 703S. Forum currently down, so I can't check.
@@EEVblog The thread is titled 'New Zoyi multimeter+oscilloscopes - ZT-70xS, up to 50MHz/250MSps (nov 2022)' - I have the tab open from before (even if the forum is currently down). I also picked up the Owon HDS2202S at the same time - it's definitely a much more polished product - just better in every way, but 3x the price too. Neither of them are my main scope - they're for places the Keysight one shouldn't go - out in the rain, on a ladder, in the back cabinet of greasy cnc machines, etc etc.
@@EEVblogThat's what I came to find out about. Is it likely to be down for long? Did someone forget to pay your bill? :D Hope it all comes good soon.
Two years ago I bought the OWON HDS272S 70 MHz Oscilloscope 3 in 1 (2 channels plus built-in function generator) with 20,000 count multi-meter. Its totally rectangular so its a bit "boxy", but its got two 18650's and every function works as it should. Its a totally usable oscilloscope (and multimeter) when I need isolation or something to carry portable, like finding a bad fuel injector on my truck.
The Zoyi does have the edge on form and style, though. I like the rounded face and the slightly curvy body - it just looks better.
I have the 100Mhz version and I'm very pleased.
In that thing the multimeter side is completely isolated, it has a switch mode power supply and 7 optocouplers, very expensive, give me more buttons instead to make it more useable.
The needle gauge (bar chart) should definitely go. No use whatsoever. BUT, I think it would be great to put a histogram (voltage vs time) in that spot, so you can see a selectable time slice of previous values (like a little o-scope). Automotive multimeters have done this for a long time, and it is very useful when you are trying to capture some kind of change in value over time and you have step away from the meter in order crank the motor/press the gas/whatever.
I would recommend paying a little more and going with the Owon HDS242S. That’s a two channel 40 MHz scope, 20,000 count meter and 25 MHz function generator. I easily found it listed for $140 US, but I assume you could find it for less. It is worth paying a little more because the Owon instrument meets or beats the promised specifications. The Owon uses two 18650s which are easily field swappable under a removable cover. Accessories are similar: carry case, meter probes, one scope probe, alligator clip co-ax cables, charger/cable, manual. I carry the 100 MHz version of the Owon in my tool bag.
It would be interesting to see an OWON review. I've got a couple of their DMMs and they are solid units.
@@button-puncher There are several reviews of the Owon HDS200 series on TH-cam. I own both the 100 MHz and 200 MHz versions. I believe the best value/price proposition is the 100 MHz model unless you need the extra bandwidth on a regular basis. There seems to be a little less noise in the vertical amplifiers of the 100 MHz model even though it uses a multiplexed ADC chip versus dual ADC chips of the 200 MHz version. I’ve got an Owon clamp multimeter in my tool bag too and it is surprisingly good, not as nice as a Fluke, but like 1/6th the cost.
@@wtmayhew I love the DATA LOGGING function through blue tooth on OWON. I OWN couple OWONS and very happy with their quality.
Yep, I have the 100MHz model in my toolbag as well. It's been handy when working on cars and seems pretty well sorted, no major bugs. As usual with these things they can be a bit frustrating to use compared to a bench scope, but that's always going to be true when you have buttons instead of knobs and a small screen.
I have a 70Mhz OWON for a portal scope. I dont like that continuity its very slow to respond and the battery drains itself when powered off
what's the power draw when switched off? I mean how long can I store it? Or how often will it be dead every time I need to use it?
Just taken delivery of 703S using your aliexpress link after watching your video. £76 with two sets of probes delivered to the UK in 7 days. Mine has firmware version 1.2.7 which seems to be the very latest. While testing 703S, I found a bug whereby if you make any changes the function generator settings in the 'Output Setting' menu, the time base cannot subsequently be set to any value less than 100 uS. To fix the problem, go to the 3rd menu and choose 'Default ON' to restore settings back to factory defaults.
Ooh, under the bottom can, looks like a little left over flux on the solder mask with a nice partial fingerprint In it. Quality work.
Would be interesting to see how this compares to some of the cheapest desktop oscilloscopes. At least comparing the problems and jankyness
I would love to see a review video of a good/recommended portable scope.
Rigol-like scope interface on the new one. At least the little icons and whatnot.
I'd like a graphing function (chart recorder) more than the bargraph.
Dave, do you think this MM would be okay for analysing serial comms e.g. Modbus? Thanks for the review.
Thanks for the video. In your opinion what is the best oscilloscope under $200 in the market currently?
I am really considering a handheld formfactor as I won't use it very often but am also open to buy a bench one.
Thank you
Nice review! Thanks!
Hi Dave, thanks for the review, Please could you show us how to Un Brick the 702, because what happened to you will happen to us and I can't find anything anywhere to show us how. Bob. UK
FNIRSI had a similar one called the DMT-99 which does live trend capture
Liked for the yellow pointer (no really it is better contrast). I'd like to have a compact oscilloscope as I do not have much space at home. Thank you for the review!
I bought a 702 off the back of your review of that. It's been pretty good for what I use it for, which is occasional fault finding and testing. If this two channel version had been available I'd definitely have got it for the slightly higher cost - the increased specs are definitely worth it, but I don't think I'd bother to buy it in addition.
I recently grabbed the 702 due to your video more or less because i needed another meter and didn't know if i had use for an oscilloscope and want to see if i would use it.
Apparently i do use one now that i have the option and eventhough it is pretty limited i figured out its still very handy.
now debating if i should get something like rigol to sit on my bench.
Mainly tinkering with arduino's and stuff like that.
Spotted at 19:45 that they did fix the screw clearance on the 703.
The "jitter" problem with the frequency measurement around 18:40 seems a bit odd. Both adjacent timebases 50ns and 250ns appear to work fine-ish, just the 100ns one gives 3.2MHz instead of 4MHz, suspiciously close to 4/5 of the correct value.
Is there a systematic issue with this timebase? Maybe there's a wrong denominator lookup value in the firmware somewhere?
Regarding the 23m mark, is it common to do the length-matching on the adc's digital outputs? I assume this would be only for parallel interfaces (i.e. not spi) and only for fast (>? Mhz) , and only if the traces need to travel a large distance (>? mils) ??
About time technology caught up and we get a cheap portable o-scope!
China came to the party
Would love to know what would be considered to be reliable brands for a device with similar specs and capabilities.
Like are Uni-T to be trusted?
"yeah, nah" 😁. Great review. I think I want one in spite of its A/mA range flaws.
I just bought a FNIRSI 2C23T from aliexpress for a project. Good to know these cheap Oscilloscope Multimeters aren't complete garbage.
I’m waiting for mine to arrive as well, saw this video only after buying it 😂
Dave, at 3:20.There is a small difference to be spotted. There's a little temperature/thermometer icon above the positive terminal (bottom right) at the left/old version. The new one doesn't have that.
my cheep 30 bucks china multimeter has a 10Hz bargraph. i love this litle detail and i use it sooooo often.. the Bargragh is exactly so fast like an analog meter
Thanks Dave. Good enough for Australia.!
awesome! cant wait to see this review.. now all we need is a chinese special SpecAn!
I've had a 702S in my toolbox since your last video, so I will be also buying a 703 for sure, worth it just to be able to remember to boot up in multimeter mode 🤣
Being able to have a disposable scope in your toolbox at all times is worth the entry price
702S also remembers the mode on more recent firmware updates.
@@samuraidriver4x4 that's good to know thanks
Interesting to see this. I have had a 702S for a while, and upgraded firmware twice with no problem, it now remembers the mode after power off (but not all settings). The 703S lets you view saved screenshots, which the 702S did not. However there are still glitches on the 702S, especially when zooming and scrolling through captured waveforms. So I won't be switching to the 703S, I would rather put the money towards an Owon handheld scope.
Спасибо большое! Очень подробно и понятно!🙂
My 30 year old Philips/Fluke scopemeter 95 is not going to be retired just yet.. it has a 25MHz sampler but an analog jitter added to the clock by putting a lower frequency sawtooth wave on one side of a differential clock so it does make it to 50MHz bandwidth.
I got the 702 for automotive which is my day job. It was excellent for crank, cam etc signls and with an attenuator is could show spark plug waves. I upgraded to software version 58 I believe and it's has been frustrating ever since. It struggles to do the same things it used to do just fine before.
Can you say an example of what it is stuffing up now?
One example is freezing up and being unresponsive to any button except off.
is it possible to downgrade?
When do we get a Blue EEVBlog Scope/DVOM combo meter??
They had some nice melf resistors in there. Everybody likes a good melf.
Is the XY mode any decent? (Assuming it's got one)
This scope is really nice for hobby benches and the 5 digits is very cool. This little guy can do lots before getting the big scopes out. 😎 Thanks for the video.
It looks like the bar graph is just setup for 25000 counts? Good for watching things like a DC motor speed going up and down?
Nope, the whole idea of a bargraph is that it's faster updating than the display, in this case it's not
@@EEVblog Thank you.
Nice channel. Can you tell me if one could read eye pattern from a optical pu with a digital scope. Thanks jim
Take your meds please.
It says in the manual that you should put it in the High-Speed mode for frequencies >30MHz. Maybe that's why it didn't trigger after 30MHz.
Just a general question regarding DMM/Scope Combos: Does anyone know such a device where the scope part can not only be coupled to the BNC-inputs but - at least for lower sample rates - also to the DMM inputs? I think It´d be really sexy to have such a device where you could e.g. bring up the current measurement to the time-resolved scope display. Or the resistance. Or temperature.
In other words, I´m asking for the combination of the input variability of a DMM with the measure/trigger flexibility of a scope.
Of course this seems impossible with 50MHz bandwith, but even with 10 or 50 ksample/s I would spend money on it.
Is it Android based or some proprietary embedded OS? in any event, it needs comprehensive user interface (UI) and function reprogramming to turn it into a semi-professional useful test instrument.
Looks a heck of a lot better than the “DSO Shell” cheapo portable scope I ended up buying several years ago.
that flat tipped iron, nice... brand? Love ur channel.... Queensland
_I have a UNI-T UT161B and it does not have the option for manual calibration. As such can it be computer calibrated. A 2200mF electrolytic capacitor shows 2650mF on the screen. Thank you._
So if one had to choose between the Fnirsi DPOX-180H from a few months ago and this one, which would be the best choice?
At least it does tell you to swap jacks on A vs mA... I give them credit for that.
I still have my mini dso form a decade ago, made in a mp4 player enclosure.
For the 702, i read about a year ago on the product page there is a warning that a certain firmware is NOT upgradable. I dont know if it was that firmware specifically, but I 💯% did read that
When you were using the built-in function generator, I noticed the one ground was not connected. Perhaps the probes do not share a common ground? And that might produce different signal levels?
Volt scales for the two probes were different as well.
Regarding the voltmeter: Maybe the bar graph auto-ranges no matter what? For example the meter is in a fixed (manual) lower range, maybe the bar graph will auto-range no matter what and let you know how far out of range you are relative to the fixed range selected?
I have Zoyi ZT-702 for few months usage and notice that the big drawback is the inaccuracy of amps. The good thing on this is that the measurement of Ohm and Voltage are quite accurate and the Ohm measurement can go below 0.1 Ohm which most cheap multimeter can't. So I never use to measure amps on this one, I use dedicated amp meter to do that. Another big drawback is the inability to save the last mode (but this is addressed in this ZT-703) and the battery drop quite fast when in Oscilloscope mode.
The 702S does remember the last mode with latest firmware update, no submode memory though, it just remembers whether to turn in oscilloscope or multimeter.
What is the tested accuracy on the capacitance measuring option?
Does it decode CANbus (or other protocols)?
The bargraph showing the reading in terms of counts might be vaguely useful for something, like reaching the end of a range, but like... give me min/max, frequency, ect with the extra space....
At around 11 minutes...I think the beeping is due to the battery level. The graph near the upper right is showing a rectangle with a red line; I think that's the battery level indicator.
It is a crazy price for a full product! A Fluke like that would cost a couple thousand $
It is crazy, but Fluke Scopemeters, at least the vintage one where rugged and really you get your money back because you can use them, all thay long and they never break down. Even the probe were overkill. They are expensive, but they delivers value. For casual probing I wouldnt even bother to think in a Fluke. This is hats off to the Chinesse, that made scope affordable and there is one for every budget. You can use it with some freedom,, you dont need to be so carefull ... in the event you damage the front end, you can afford another one.
@@38911bytefree Well actually i had a quick look at ebay and the Fluke 123 sells for around 400-500$. Might be worth comparing the 2. But personnally I would always prefer using a picoscope in any situation
Any recommendations for an oscilloscope for retro consoles NES to PS1?
i bought one for automotive. works great
Could you review and compare with Tooltip ET120MPRO? Thanks
Please test the ZEEWEII DSO3D12.
It seam to torch all of the other cheap Chinese hand held scope/multimeter.
As a voltmeter it is not yet a Brymenkiller. But because it is all singing and dancing the blue ones could be the Brylcream for the red's hair?
for the price..thats really nice for a maker or tinkerer...
it says "1 probe" on the screenshot you showed. like ALL the descriptions, the link shows the cheapest price for some option, then one is forced to read the screen. ;-) i bought this for my own work, with the Rigol DHO800/900 series on deck, based on your reviews.
Thanks!
For checking EV chargers, this all in one solution would work just fine.
For automotive services, it would be nice if it could read CAN messages.
It clearly has a cell charging capability. How long does it take to charge it to let say 50%, so you can continue working in the field if the battery is flat?
X-Y mode on dual ch for testing Shaft encoders?
I'd love to see the TEMPERATURE reading back, as the 702S had.
Can it measure inrush currents?? What is the best device for inrush measurement? I need to test LED installations for inrush. Also some relay inrushes.... As an electrician. 230V AC
Unit ut 216 , with this cheap oszi you can measure thinks Like this save. I have owon ,ist a Bit netter as zoyi Bit the multimeter works Like a 20 USD multimeter . Not very nice. The zoyi works a Bit better as multimeter as the owon. But not for current and goes only to 300v whats in Europe useless . So you have to Go for a real device Like unit or Fluke Ar similar.
This would be an awesome product if they could isolate the two BNCs from each other.
Imagine a sub $100 50mhz handheld 2cb scope with isolated probes.
I will wait for the next version without the speedometer ZT-704S when?
It can be very useful to connect probes without worrying about grounding. SMPSes in particular must be responsible for too many early scope deaths.
Agree, bar graph must be scaled to the selected range to be useful. I have never used the bar graph on a meter - what, I have a digital readout and I want to see if is about ... Larger digits would be better.
I just got one. I've never had a scope before and the price seems right to learn with this, especially as it seems somewhat rugged and more splash proof than a bench scope. Also, it wouldn't be a big deal if it died somehow
Best digital bar graph i saw was on my fluke 990 copperpro. That was best at testing insulation and seeing if it breaks down though
The lcd display looks cool Does anyone have any idea where I can buy one ? I need it for one of my projects
Looks similar to my ET829 80Mhz but it's got a sig gen and DMM good cap testing etc. I like it. I want to use dual scope mode to run a dual input curve tracer component tester kit. 2x 18650! Just get ET829 for a bit extra. Why not?!
Can I yank the display out and use it to upgrade my GBA SP?
Is there something to calibrate it?
Awesome device need to buy one 👍 But yeah the bar graph should be removed or fixed :)
I want to know what they do to unbrick the old one for you now!
The problem with screwing the probe in lock-tight-position is with the sticker on the bottom of the case for the BNC terminals. The tolerance is too small, e.g. the sticker is thick enough to block screwing the probe in the right position. The problem with this is that, if you don't set the probe right, you'll never know wheather the measurement is correct or not. I have removed the sticker under the terminal (leaving the half to cover the other hole on Zoyi ZT-702) and now the probe (and every other BNC connector) locks in place.
So Dave actually writes home to his Mum with the component level descriptions of the electronic gadgets he tears down?
Dave, I think you missed the measurements on the screen when you thought there was something wrong with the probes, at 15:15 the yellow channel is reading a volt per division and the blue channel is reading 100, why does it default to that, IDK, but that's the difference you're seeing.
Thanks