New Zoyi multimeter+oscilloscopes - ZT-70xS, up to 50MHz/250MSps (nov 2022)

[nikbry]

@ Nikbry, is this choise for FW 1.32 a conscious choise based on some criteria that were important to you or did you just stick with it over time more like randomly?
In the first case I could decide to start with 1.32 too. If it is the latter I'd could just start with what it comes with, or even the latest one and stick with it from there.

In my mind an oscilloscope has to do at least three things correctly:

1) Display the right waveform without distortions or artifacts (sine, square, AM, FM, pulse, etc)
2) Trigger reliably
3) Display data accurately and as precisely as possible

To answer your question:

FW 1.32

1) Displays the waveform correctly, except: a) with medium/high MHz signals  a jitter becomes evident b) at very low frequencies and large time bases periodic signals show a somewhat randomly appearing distortion of the wave.

2) Trigger works reliably (FW 1.38 and upwards introduced trigger HD and Peak, and corrected the jitter. This broke the trigger function, specially with fast pulses. Autorange was broken too.)

3) The measurements done by the scope are mostly inaccurate for voltages and OK for frequency and period. I suggest you use the cursors to get a better quantification. This is true for all FW versions.

Some minor problems of FW1.32 are that when you autorange with no signal, CH2 activates itself. Also when holding an image the cursor lines sometimes disappear when moving them.
With FW1.32 you miss out on: the trigger peak/HD option, the FFT function, ...

The biggest problem with my unit and @IC_Toaster's seems to be a hardware one. In my case at 10x probe setting I do have a noticeable signal attenuation in @IC Toaster's it's even more severe.
The normal behavior of the Zoyi should be to see no attenuation up to 10MHz.

If you can, get access to a reliable signal generator (and ideally a second reliable oscilloscope) and test your unit to see how it behaves.

The Zoyi firmware works just fine on an Aneng.

A good beginner's exercise with an oscilloscope is to "design" RC low pass, high pass, band filters. Here are two links:

https://www.homofaciens.de/technics-base-circuits-rc-circuit_en.htm
https://www.electronics-tutorials.ws/filter/filter_1.html

[gazsiazasz]

I cannot update the firmware from 1.3.9 to 1.4.2 because it says the disk is full. (it says 592k is free from the 608k, but the fw file is 636k)

How to overcome this issue?

[nikbry]

I cannot update the firmware from 1.3.9 to 1.4.2 because it says the disk is full. (it says 592k is free from the 608k, but the fw file is 636k)

How to overcome this issue?

How about deleting some screenshots to free up space?

[xKertx]

but about the firmware, anyone else owning the aneng version.
Can one use the zoyi FW?
this seems to be a question that has been asked before, but i haven't found an conclusive answer on yet (I might have just read over it though)

Yes, you can use zoyi FW. It's the same unit with different labels.
I personally think the latest FW works best.
Yes, it still has some bugs, but many bugs are fixed and the autoset works also.
I don't unerstand why would anyone want to use old firmware intentionally. The old FW does not have nothing that the latest FW don't have.

In addition to calibration, also remember to compensate the probes properly. And don't swap probes after that (use the colourcoded rings to identify them).
If you adjusted one probe to match CH1, then use it in CH1. And if you want to use it in CH2 then you would need to re-adjust it's compensation.

[nikbry]

but about the firmware, anyone else owning the aneng version.
Can one use the zoyi FW?
this seems to be a question that has been asked before, but i haven't found an conclusive answer on yet (I might have just read over it though)

Yes, you can use zoyi FW. It's the same unit with different labels.
I personally think the latest FW works best.
Yes, it still has some bugs, but many bugs are fixed and the autoset works also.
I don't unerstand why would anyone want to use old firmware intentionally. The old FW does not have nothing that the latest FW don't have.

In addition to calibration, also remember to compensate the probes properly. And don't swap probes after that (use the colourcoded rings to identify them).
If you adjusted one probe to match CH1, then use it in CH1. And if you want to use it in CH2 then you would need to re-adjust it's compensation.

I'll try not to take your somewhat harsh comment offensively... I don't understand why people just install the newest firmware 1.42, even if it has critical issues like a faulty trigger. It must be the sign of the times of updating frenzy...
And YES the Autorange on 1.42 is much worse than on 1.32. Try it.

Also the issues I described with the attenuation have nothing to do with the probes or their compensation, this has been discussed by IC_Toaster and myself....

[indman]

In my mind an oscilloscope has to do at least three things correctly:
1) Display the right waveform without distortions or artifacts (sine, square, AM, FM, pulse, etc)

I agree, but since now the oscilloscope does not reliably cope with this most important function №1, all other conditions become secondary. This is especially true for a portable instrument, as it is often the only tool an engineer has in the field. If I need to find a fault in the circuit, I do not have to guess what exactly distorts the shape of the signal - oscilloscope or some faulty element in the circuit. And I'm not going to pester people to provide me with a more reliable tool to analyze it. Buy a toy to find bugs in it and play continuously with version updates that remove old bugs and add many new ones - these adventures are not for me. I apologize if my harsh comment offended anyone.

[xKertx]

And YES the Autorange on 1.42 is much worse than on 1.32. Try it.

I have tried both. The autoset works fine with 1.42. Atleast on my unit.

Also the issues I described with the attenuation have nothing to do with the probes or their compensation, this has been discussed by IC_Toaster and myself....

I answered to spikey, who said is new to oscilloscopes.
But the same applies to all oscilliscopes, even expensive ones. If you swap the probe to other channel, you should to check the compensation.

I am a newbee on Scopes, I have a basic theory on how to use them...
Additionally I was wondering if there are special things I need to do before using the scope tool

[matefon]

To gazsiazasz (#776):
I had a similar issue that prevented me from capturing screenshots. When I tried, it showed that it failed to take a screenshot. I had a couple of pictures on the device, but for some reason all of them disappeared. When I tried to revert the firmware, my PC showed just the empty screenshot folder, nothing else. I panicked, but after a reset from the oscilloscope menu (I think it's called "reset settings" or something like that), I could take screenshots and USB mode works now just fine. After that, I couldn't reflash the latest firmware because it was saying I don't have sufficient memory. I installed 1.39 without a problem, then flashed 1.42.
I have no idea what caused the device to soft-brick itself.

[spikey1973]

@nikbry

thank you, a very informative and constructive response.
I actually have a signal generator i could use (fairly descent one I believe),
I also have some sort of USB scope, but I never seem to use this, it is (for me personally) to much of an hassle.. but at least I have some sort of fall back when I need to compare stuff..
even though its not the best one either, it misses a lot of option like bandwith/sample rate, also it is also fairly old by now so.

about the firmware version, I do tend to be someone that prefers the latest FM, but in case of a faulty trigger.. well, lets say I will be seriously rethinking things.  seems rather important / critical to me.

@xKertx
thank you, I would've understand that one would need to check compensation when swapping probes,
but I gues it could've skipped my mind. So it is good you pointed it out to me. thank you.

Do you do have trigger issues with 1.4.2?

@Indman, I completely understand your point of view, and absolutely correct and essential for a professional, but for me I feel I can and will just have to deal with it for now.

I tried to look around for a good textbook on oscilloscope usage and bumped into the following:

* oscilloscopes: a manual for students engineers and scientists by David Herres

does anyone have any reccommendations on if this is worth the time and effort?

Kind greats

Matthieu

[nikbry]

Do you do have trigger issues with 1.4.2?

I get the feeling that you didn't read the thread in detail...

Look at page 29 reply 706, which illustrates the trigger issue on FW 1.42

https://www.eevblog.com/forum/testgear/new-zoyi-multimeteroscilloscopes-zt-70xs-up-to-50mhz250msps-(nov-2022)/700/

[csuhi17]

I cannot update the firmware from 1.3.9 to 1.4.2 because it says the disk is full. (it says 592k is free from the 608k, but the fw file is 636k)

How to overcome this issue?

I have about 10MB of free space with two pictures.
the other 3.4MB is some kind of hidden file.
Looking in the Windows file manager, I only have files in the "pic" folder, the others seem to be empty.

Do you do have trigger issues with 1.4.2?

I get the feeling that you didn't read the thread in detail...

Look at page 29 reply 706, which illustrates the trigger issue on FW 1.42

https://www.eevblog.com/forum/testgear/new-zoyi-multimeteroscilloscopes-zt-70xs-up-to-50mhz250msps-(nov-2022)/700/

That post is partly wrong, I later wrote that my method was wrong.
I wanted to continuously give a 2V sine wave to the scope, set the trigger to 3V and check with a single trigger what the wave is like, how long the delay is between the green arrow of the trigger and the real first trigger point. And to see if there is any distortion.

Unfortunately, I didn't know my signal generator well enough, I didn't know that if I changed the voltage, it would turn off the output and then turn it back on. This is why my measurement is not correct.

I tested it with a 1kHz 5Vpp color, which I checked on my sure-to-be-good scope.

At 250ns there is a slight delay in the trigger.
That doesn't mean it's unusable.

[IC_Toaster]

@ Nikbry, is this choise for FW 1.32 a conscious choise based on some criteria that were important to you or did you just stick with it over time more like randomly?
In the first case I could decide to start with 1.32 too. If it is the latter I'd could just start with what it comes with, or even the latest one and stick with it from there.

In my mind an oscilloscope has to do at least three things correctly:

1) Display the right waveform without distortions or artifacts (sine, square, AM, FM, pulse, etc)
2) Trigger reliably
3) Display data accurately and as precisely as possible

To answer your question:

FW 1.32

1) Displays the waveform correctly, except: a) with medium/high MHz signals  a jitter becomes evident b) at very low frequencies and large time bases periodic signals show a somewhat randomly appearing distortion of the wave.

2) Trigger works reliably (FW 1.38 and upwards introduced trigger HD and Peak, and corrected the jitter. This broke the trigger function, specially with fast pulses. Autorange was broken too.)

3) The measurements done by the scope are mostly inaccurate for voltages and OK for frequency and period. I suggest you use the cursors to get a better quantification. This is true for all FW versions.

Some minor problems of FW1.32 are that when you autorange with no signal, CH2 activates itself. Also when holding an image the cursor lines sometimes disappear when moving them.
With FW1.32 you miss out on: the trigger peak/HD option, the FFT function, ...

The biggest problem with my unit and @IC_Toaster's seems to be a hardware one. In my case at 10x probe setting I do have a noticeable signal attenuation in @IC Toaster's it's even more severe.
The normal behavior of the Zoyi should be to see no attenuation up to 10MHz.

If you can, get access to a reliable signal generator (and ideally a second reliable oscilloscope) and test your unit to see how it behaves.

The Zoyi firmware works just fine on an Aneng.

A good beginner's exercise with an oscilloscope is to "design" RC low pass, high pass, band filters. Here are two links:

https://www.homofaciens.de/technics-base-circuits-rc-circuit_en.htm
https://www.electronics-tutorials.ws/filter/filter_1.html

I have attenuation even in DC.
Someone commented that it is importanto to know your measuring instrument. Of course it is, but you need also a reliable instrument to compare when the instrument under test is working right and when is having a bug. Otherwise you can't know a measuring instrument which has bugs.

but about the firmware, anyone else owning the aneng version.
Can one use the zoyi FW?
this seems to be a question that has been asked before, but i haven't found an conclusive answer on yet (I might have just read over it though)

Yes, you can use zoyi FW. It's the same unit with different labels.
I personally think the latest FW works best.
Yes, it still has some bugs, but many bugs are fixed and the autoset works also.
I don't unerstand why would anyone want to use old firmware intentionally. The old FW does not have nothing that the latest FW don't have.

In addition to calibration, also remember to compensate the probes properly. And don't swap probes after that (use the colourcoded rings to identify them).
If you adjusted one probe to match CH1, then use it in CH1. And if you want to use it in CH2 then you would need to re-adjust it's compensation.

I'll try not to take your somewhat harsh comment offensively... I don't understand why people just install the newest firmware 1.42, even if it has critical issues like a faulty trigger. It must be the sign of the times of updating frenzy...
And YES the Autorange on 1.42 is much worse than on 1.32. Try it.

Also the issues I described with the attenuation have nothing to do with the probes or their compensation, this has been discussed by IC_Toaster and myself....

I agree. The signal amplitud shown and the measurement given by the device coincide and it makes me think it is not a software problem. But it is important to determine when it happens to find a behaviour pattern in order to know our measurement instrument.

In my mind an oscilloscope has to do at least three things correctly:
1) Display the right waveform without distortions or artifacts (sine, square, AM, FM, pulse, etc)

I agree, but since now the oscilloscope does not reliably cope with this most important function №1, all other conditions become secondary. This is especially true for a portable instrument, as it is often the only tool an engineer has in the field. If I need to find a fault in the circuit, I do not have to guess what exactly distorts the shape of the signal - oscilloscope or some faulty element in the circuit. And I'm not going to pester people to provide me with a more reliable tool to analyze it. Buy a toy to find bugs in it and play continuously with version updates that remove old bugs and add many new ones - these adventures are not for me. I apologize if my harsh comment offended anyone.

I think the same. In the field you need to trust your measurement instrument because in some situations you have only that device and depending on the result given by it you have to take decisions.

@nikbry

thank you, a very informative and constructive response.
I actually have a signal generator i could use (fairly descent one I believe),
I also have some sort of USB scope, but I never seem to use this, it is (for me personally) to much of an hassle.. but at least I have some sort of fall back when I need to compare stuff..
even though its not the best one either, it misses a lot of option like bandwith/sample rate, also it is also fairly old by now so.

about the firmware version, I do tend to be someone that prefers the latest FM, but in case of a faulty trigger.. well, lets say I will be seriously rethinking things.  seems rather important / critical to me.

@xKertx
thank you, I would've understand that one would need to check compensation when swapping probes,
but I gues it could've skipped my mind. So it is good you pointed it out to me. thank you.

Do you do have trigger issues with 1.4.2?

@Indman, I completely understand your point of view, and absolutely correct and essential for a professional, but for me I feel I can and will just have to deal with it for now.

I tried to look around for a good textbook on oscilloscope usage and bumped into the following:

* oscilloscopes: a manual for students engineers and scientists by David Herres

does anyone have any reccommendations on if this is worth the time and effort?

Kind greats

Matthieu

You what to buy a book to learn to use oscilloscopes without having a serious oscilloscope. I think that won't work.

I cannot update the firmware from 1.3.9 to 1.4.2 because it says the disk is full. (it says 592k is free from the 608k, but the fw file is 636k)

How to overcome this issue?

I have about 10MB of free space with two pictures.
the other 3.4MB is some kind of hidden file.
Looking in the Windows file manager, I only have files in the "pic" folder, the others seem to be empty.

Do you do have trigger issues with 1.4.2?

I get the feeling that you didn't read the thread in detail...

Look at page 29 reply 706, which illustrates the trigger issue on FW 1.42

https://www.eevblog.com/forum/testgear/new-zoyi-multimeteroscilloscopes-zt-70xs-up-to-50mhz250msps-(nov-2022)/700/

That post is partly wrong, I later wrote that my method was wrong.
I wanted to continuously give a 2V sine wave to the scope, set the trigger to 3V and check with a single trigger what the wave is like, how long the delay is between the green arrow of the trigger and the real first trigger point. And to see if there is any distortion.

Unfortunately, I didn't know my signal generator well enough, I didn't know that if I changed the voltage, it would turn off the output and then turn it back on. This is why my measurement is not correct.

I tested it with a 1kHz 5Vpp color, which I checked on my sure-to-be-good scope.

At 250ns there is a slight delay in the trigger.
That doesn't mean it's unusable.

I don't understand what you try to show there because I don't see any relationship between the three images. I must have lost something.

[csuhi17]

I wrote it because of the trigger bug.
Around post 706, it was said that one of two rapid pulses in a row is lost.
We didn't know if it was a memory bug or something else, so I'm testing it based on what I described above, which led me astray. I don't know my signal generator well enough.

In the current three pictures.
I recorded the beginning of a slow sine wave at 250ns/div. With single trigger. PIC_6520.png
In order to rule out the case when the previous waves in the memory are still visible.

Then I shrunk it to 100us/div setting.PIC_6521.png
In order to see how much the trigger is "delayed"
And how does the wave that is in the memory look like.

Occasionally, there can be quite a big difference between the first trigger point and the point triggered by zoyi. I have already measured a delay of 6-7us, 11us, 44us.

Zoyi has some memory management issues and I've noticed that it sometimes trashes the wave.

The third picture is just a check to make sure I don't make the same mistake as in my previous test. where I didn't know that my signal generator turns off the output for several ms if I change the voltage.

At PIC_6521.png you can see a cut on the wave, it was not done by my signal generator, it is some kind of bug of Zoyi.

I hope they fix it this year.

[IC_Toaster]

I wrote it because of the trigger bug.
Around post 706, it was said that one of two rapid pulses in a row is lost.
We didn't know if it was a memory bug or something else, so I'm testing it based on what I described above, which led me astray. I don't know my signal generator well enough.

In the current three pictures.
I recorded the beginning of a slow sine wave at 250ns/div. With single trigger. PIC_6520.png
In order to rule out the case when the previous waves in the memory are still visible.

Then I shrunk it to 100us/div setting.PIC_6521.png
In order to see how much the trigger is "delayed"
And how does the wave that is in the memory look like.

Occasionally, there can be quite a big difference between the first trigger point and the point triggered by zoyi. I have already measured a delay of 6-7us, 11us, 44us.

Zoyi has some memory management issues and I've noticed that it sometimes trashes the wave.

The third picture is just a check to make sure I don't make the same mistake as in my previous test. where I didn't know that my signal generator turns off the output for several ms if I change the voltage.

At PIC_6521.png you can see a cut on the wave, it was not done by my signal generator, it is some kind of bug of Zoyi.

I hope they fix it this year.

I think now I undestand what you mean.
I have also noticed that the signal is capturated quite after the triger point and the scope makes you think the signal is not captured but when you change the time base to a larger value you find the signal, as you represented.
Notice also that the maximun value of the signal at PIC_6512 is 2,5V but the measure says 1,8V.
I don't understand why the signal is cut either.
Because of what you have shown, could we can say it is unusable? What is the utility of a measuring instrument which cut the signals and give wrong measurements?

[spikey1973]

@IC_toaster

I am not looking for a book to learn to use a oscilloscope but to understand the theory behind it in more depth.
sorry if i wasn't clear in that. But generally speaking books tend to be ggod for theoretics.

But also, I am not buying a book, plenty of books are available through official site in pdf. this one is too (#no torrent)
But I read through it and it is definately not usefull, not forme at this point anyway.

@nikbry
and yeah, I didn't read the full thread completely. by the time i was on page 25 i started to read more and more diagnolly. so I acdmitt I missed that part. but thank you for pointing it out to me.

still the question remains does anyone know a good book for more in depth theories on oscilloscopes.

Kind greats

Matthieu

 
 

[nikbry]

@IC_toaster

I am not looking for a book to learn to use a oscilloscope but to understand the theory behind it in more depth.
sorry if i wasn't clear in that. But generally speaking books tend to be ggod for theoretics.

But also, I am not buying a book, plenty of books are available through official site in pdf. this one is too (#no torrent)
But I read through it and it is definately not usefull, not forme at this point anyway.

@nikbry
and yeah, I didn't read the full thread completely. by the time i was on page 25 i started to read more and more diagnolly. so I acdmitt I missed that part. but thank you for pointing it out to me.

still the question remains does anyone know a good book for more in depth theories on oscilloscopes.

Kind greats

Matthieu

Not sure what you mean with "in depth theories on oscilloscopes", you should maybe state what you are interested in: mastering its use, designing one, practical applications with examples?  Maybe the subject is worth starting its own thread instead of hijacking this one ....

[indman]

What is the utility of a measuring instrument which cut the signals and give wrong measurements?

The usefulness of such a tool tends to zero and it cannot be called a measuring tool. It's just a toy.

[apollo11fan]

Respectfully, and no offense in the slightest intended to Indman - the simplest of objects: a stick or a wooden box can be extremely handy tools. So is a pencil or piece of chalk.
Might we agree - we could put a junior technician in possession of the best in portable Fluke or Techtronix instrumentation, but if they didn't know how to use the devices, the outcome of their efforts with same would be dubious.

This class of device being produced now are experiencing growing pains. I'm a proponent of helping Zoyi discover and correct tool shortcommings where possible / practical, not dwelling on how these aren't multi-thousand dollar test equipment items used by highly experienced people, or devices of medium price-point beginners would have trouble affording out of the gate.

While there are going to be shortcomings and real compromises in terms of hardware for low-end equipment, the utility and the performance of this particular product we are discussing - aimed at people without a lot of extra $$$ comes down to software maturity.
In otherwords, before we shoot them, IMHO there is an opportunity space for additional development, test and validation that remains here.

[nikbry]

Respectfully, and no offense in the slightest intended to Indman - the simplest of objects: a stick or a wooden box can be extremely handy tools. So is a pencil or piece of chalk.
Might we agree - we could put a junior technician in possession of the best in portable Fluke or Techtronix instrumentation, but if they didn't know how to use the devices, the outcome of their efforts with same would be dubious.

This class of device being produced now are experiencing growing pains. I'm a proponent of helping Zoyi discover and correct tool shortcommings where possible / practical, not dwelling on how these aren't multi-thousand dollar test equipment items used by highly experienced people, or devices of medium price-point beginners would have trouble affording out of the gate.

While there are going to be shortcomings and real compromises in terms of hardware for low-end equipment, the utility and the performance of this particular product we are discussing - aimed at people without a lot of extra $$$ comes down to software maturity.
In otherwords, before we shoot them, IMHO there is an opportunity space for additional development, test and validation that remains here.

Absolutely, amen to that! And thank you for expressing it so eloquently.

It’s like how pilots are taught to "fly the plane first!"—stay in control and question your instruments at all times.
Even the best Fluke or Tektronix tools are useless if the user doesn’t know how to use them or doesn't understand its limitations.

[spikey1973]

@nikbry

I meant, 'mastering its use', sorry if this wasn't clearly stated by me.
But I agree, it might be a thread high-jack, and that was definately not intended as such.

@apollo11fan
well thank you! very nicely stated.

Kind greats

Matthieu

[spikey1973]

Small other question,

From what I read in this thread, i understand that the probes this 'toy' comes with are not really good at all. Is this correct? I did read the recommendation to get a pair of p6100 probes, so I will look into that but now for the time being I have some Uni-T P03 probes 60Mhz probes. Can I judge this as even so slightly better then the ones the ZT703 comes with or not at all? Does anyone have any experience  with UT probes? I looked for some reviews on them but didn't find any, none on any of there probes really.

Kind greats

Matthieu.

[nikbry]

Small other question,

From what I read in this thread, i understand that the probes this 'toy' comes with are not really good at all. Is this correct? I did read the recommendation to get a pair of p6100 probes, so I will look into that but now for the time being I have some Uni-T P03 probes 60Mhz probes. Can I judge this as even so slightly better then the ones the ZT703 comes with or not at all? Does anyone have any experience  with UT probes? I looked for some reviews on them but didn't find any, none on any of there probes really.

Kind greats

Matthieu.

Look at page 31, post #756 where @IC_Toaster did some tests comparing the P6100 to a Zoyi and a Sigilent.

[spikey1973]

Oke I recieved it today, and was ofcourse very happy.

But after a few hours trying to do just some basic stuff i have decided. it's going back.

so now it's time for me to read back on all the other alternate proposals that were made over time
anyway (not wanting to hijack the thread again, but general though of people here that are not on the Zeeweii Dso3d12?
seems similar, to wat Aldo22 suggested in a diff thread, the DSO1C81 . in his words, it seems to be more mature.

[indman]

But after a few hours trying to do just some basic stuff i have decided. it's going back.

What happened that you came to this decision? Previously, you convincingly and solemnly assured that this instrument was created just for you!
Who then will help Zoyi detect and correct tool deficiencies?

[spikey1973]

Never claim to be anywhere near skilled enough to do thaat. you would be much better at that IMHO.

Kind greatz


Matthieu