New 2ch pocket DSO+SG - Zeeweii DSO2512G

[Aldo22]

Compare your results with my results. As you see Zeeweii is not to apart from the Siglents scopes

Yes, I actually find it amazingly precise for such a basic device.

I'll check everything with the FY3224S, which I've only had for a few days.
This is also a basic device, but at least it can generate 20Vpp and DC offsets (also negative) etc.

I will check whether there are deviations in the various vertical sensitivities.
How accurately it measures DC and negative DC, how the two channels match etc.

If I find substantial deviations (>2-3%) I will do the update, otherwise maybe later or never.

[ptluis]

Thank you for the answers! 

3. how is the automatic calibration via menu related to this manual calibration?
Automatic calibration is part of the upgrade procedure, after the scope updates the firmware it enters the calibration mode automatically. You can always enter this mode manually

I would be interested to know if it affects the same parameters. Does a manual calibration override the automatic calibration and vice versa?
Have you ever tried a downgrade to the original version?
Will an automatic calibration make everything normal again, or were parameters manually changed that I can no longer reach with the original version?

If you don't feel confident and are happy how your scope operates, honestly you shouldn't do it. Like I said you need to have a stable FG so that calibration is done properly .

I actually think that a FY3224S would be sufficient.
It is not very accurate to adjust, but it generates a stable 1 kHz sine wave at ~2.5 Vpp.
I can adjust the amplitude (mV) using the An870.
The feeltech AWGs can also be adjusted, but I'm not sure that makes much sense.


I would like to try it, but actually my DSO2512G is not that far off on the measurements. I'm not sure if I can even get it to be more accurate.
And so I'm still hesitant...

Thank you.

I see we are having a communication problem  "Automatic calibration" means the scope enters into the calibration function automatically BUT you need to adjust the values manually. It's the same as manual mode. Entering this function automatically after upgrading the firmware is part of the upgrade procedure.

I never downgrade to the original firmware, zeeweii sent me the original firmware in case i wanted to revert back. I won't revert back because this firmware is stable and doesn't mess with the other functions, just adds zoom and the hidden calibration function

Like i said before if you like the way your scope works be on the safe side and Don't upgrade. if one day for some reason you see your scope is way out of specs you have the firmware and try it.

[ptluis]

Compare your results with my results. As you see Zeeweii is not to apart from the Siglents scopes

Yes, I actually find it amazingly precise for such a basic device.

I'll check everything with the FY3224S, which I've only had for a few days.
This is also a basic device, but at least it can generate 20Vpp and DC offsets (also negative) etc.

I will check whether there are deviations in the various vertical sensitivities.
How accurately it measures DC and negative DC, how the two channels match etc.

If I find substantial deviations (>2-3%) I will do the update, otherwise maybe later or never.

Turn your FG on at least 15 minutes,  before doing any kind of calibration so that it stabilize in operating temperature

[Aldo22]

I see we are having a communication problem  "Automatic calibration" means the scope enters into the calibration function automatically BUT you need to adjust the values manually. It's the same as manual mode. Entering this function automatically after upgrading the firmware is part of the upgrade procedure.

Yes, communication problem. 
Let's try with a picture.
I mean by "automatic calibration" what you can trigger in the "Aux" menu. (-> Attached photo).
My question is: Does a manual calibration override the automatic calibration (from the "Aux" menu) and vice versa?

[ptluis]

I see we are having a communication problem  "Automatic calibration" means the scope enters into the calibration function automatically BUT you need to adjust the values manually. It's the same as manual mode. Entering this function automatically after upgrading the firmware is part of the upgrade procedure.

Yes, communication problem. 
Let's try with a picture.
I mean by "automatic calibration" what you can trigger in the "Aux" menu. (-> Attached photo).
My question is: Does a manual calibration override the automatic calibration (from the "Aux" menu) and vice versa?

No no no! we are talking about different things here. The calibration added to the plus firmware is a function to adjust the measurements values, meaning the Vpp and Mean. it's all explained in the log.txt file. The auto calibration you show in picture is another thing and you should do it after the firmware upgrade steps completed at least i did it.

The plus firmware allows you to enter a hidden function where you can manually adjust the values of the Vpp and Mean measurements to correct the displayed values.

This function is usefull if for example after an automatic calibration (the one you show in picture)  to make corrections on the values displayed in Vpp and Mean . This is how they calibrate the measurements on this scope.

The auto cal you show in picture must be done if you change places or when temperatures changes

I hope i made myself clear this time

[ptluis]

Added some text in the <calibration> section of the firmware post

[Aldo22]

I will probably upgrade. No risk, no fun. 

There's just something I don't quite understand yet:
After the DSO will be upgraded and restarts (with God's help), do I then have to calibrate manually directly as a step in the upgrade procedure, or can I start the device normally and calibrate/adjust later?

I ask among other things because I would then warm up the FY3224S for 15 minutes before upgrading, as you suggested.

Thank you.

[ptluis]

I will probably upgrade. No risk, no fun. 

There's just something I don't quite understand yet:
After the DSO will be upgraded and restarts (with God's help), do I then have to calibrate manually directly as a step in the upgrade procedure, or can I start the device normally and calibrate/adjust later?

I ask among other things because I would then warm up the FY3224S for 15 minutes before upgrading, as you suggested.

Thank you.

after the scope restarts it enters the manual calibration automatically. read the log.txt file to find out about the keys to operate on this mode. If after it you don't like the results you can later enter this hidden function and do manual calibration of the measurements as many times you wish.

The 15 min wait time for the FG, is to allow it to stabilize in a proper working condition so that the output sinal become the most stable as possible.

You can also use your multimeter connected at the same time to compare with the values displayed on the scope, specially when doing DC calibration vs Mean value on the scope.

[Aldo22]

OK, the upgrade worked smoothly.
So far so good. It is not bricked. 

A little irritating is that it is set to Chinese after the upgrade.
I was a bit helpless at the "Gain Calib" screen after power on. But after pressing OK you are in normal mode and you can switch the language.

I will experiment with the manual adjustment later.
After an "auto calib" it is already usable again.

Thanks for the FW and for the support! 

[ptluis]

OK, the upgrade worked smoothly.
So far so good. It is not bricked. 

A little irritating is that it is set to Chinese after the upgrade.
I was a bit helpless at the "Gain Calib" screen after power on. But after pressing OK you are in normal mode and you can switch the language.

I will experiment with the manual adjustment later.
After an "auto calib" it is already usable again.

Thanks for the FW and for the support! 

I'm glad everything went smoothly my friend. You can easily calibrate de measurements latter, is a little tricky to enter into that mode, but i think you can do it without much problems.
Enjoy your "new" scope!

[Aldo22]

I'm glad everything went smoothly my friend. You can easily calibrate de measurements latter, is a little tricky to enter into that mode, but i think you can do it without much problems.
Enjoy your "new" scope!

Thank you!

Here you can see my improvised adjustment setup, including 1980s programmable Pocket Computer Casio FX-710P. 
The Casio is still useful to do e.g. quick RMS -> PkPk conversions.

So far, the accuracy looks very good.
Only in the negative DC range I probably won't get it right.
But well, it is an oscilloscope, not a voltmeter. 

[ptluis]

I'm glad everything went smoothly my friend. You can easily calibrate de measurements latter, is a little tricky to enter into that mode, but i think you can do it without much problems.
Enjoy your "new" scope!

Thank you!

Here you can see my improvised adjustment setup, including 1980s programmable Pocket Computer Casio FX-710P. 
The Casio is still useful to do e.g. quick RMS -> PkPk conversions.

So far, the accuracy looks very good.
Only in the negative DC range I probably won't get it right.
But well, it is an oscilloscope, not a voltmeter. 

wow the Casio is piece of art! I had one in my school days. Really nice to see one working 

For DC you set your FG to DC wave and adjust until Mean measure on scope get equal or close to the set value. You could use your multimeter at same time for a more precise adjustment.

[Aldo22]

wow the Casio is piece of art! I had one in my school days. Really nice to see one working 

Yes, it's a cute thing!
It looks like new and works like new (see attachment).
It must be 40 years old soon.
I like the dedicated buttons more than touch screens and it's very straightforward to use for programmed calculations like this.

For DC you set your FG to DC wave and adjust until Mean measure on scope get equal or close to the set value. You could use your multimeter at same time for a more precise adjustment.

Have you tried this out yet?
The problem is that if it's accurate for DC+, it's not equally accurate for DC-. I can only change one offset though.
Probably a hardware thing (of my HW version?).

On the other hand, let's not exaggerate. It's maybe 3-4% off in the negative DC range.
As I said, it's not a voltmeter.

Thanks.

[ptluis]

wow the Casio is piece of art! I had one in my school days. Really nice to see one working 

Yes, it's a cute thing!
It looks like new and works like new (see attachment).
It must be 40 years old soon.
I like the dedicated buttons more than touch screens and it's very straightforward to use for programmed calculations like this.

For DC you set your FG to DC wave and adjust until Mean measure on scope get equal or close to the set value. You could use your multimeter at same time for a more precise adjustment.

Have you tried this out yet?
The problem is that if it's accurate for DC+, it's not equally accurate for DC-. I can only change one offset though.
Probably a hardware thing (of my HW version?).

On the other hand, let's not exaggerate. It's maybe 3-4% off in the negative DC range.
As I said, it's not a voltmeter.

Thanks.

Your casio looks like new, it's a nice piece of engineering, I used one maybe 40 years ago, it was a luxury owning one at that time. Mine didn't last so much time maybe 20 or so much years.

About the DC calibration I only adjusted the positive DC. I adjusted the Mean measurement of the scope to be as close as possible to the DC signal Voltage, i also used a multimeter in this case UT61E at same time to certify the correct DC value. you can adjust Vpp or DC independently. I was able to adjust each value with a precision of 2 digits in the mV range. But of course this is a cheap scope and may occur some deviation when it's not operated in ideal temp, but anyway it's according to specs. It's not a multimeter but it's enough for many task and I can save my good equipment in situations where a mistake could blow it.

[Aldo22]

About the DC calibration I only adjusted the positive DC. I adjusted the Mean measurement of the scope to be as close as possible to the DC signal Voltage, i also used a multimeter in this case UT61E at same time to certify the correct DC value. you can adjust Vpp or DC independently. I was able to adjust each value with a precision of 2 digits in the mV range. But of course this is a cheap scope and may occur some deviation when it's not operated in ideal temp, but anyway it's according to specs. It's not a multimeter but it's enough for many task and I can save my good equipment in situations where a mistake could blow it.

Yes.
After some fiddling, I am happy now. 
The effort with the upgrade was worth it.
Attached are a few examples: 50mV, 100mV, 500mV, 5V, 20V (Roughly, the SG has steps), and DC: +2V, +3V, +5V.
Considering that the signal comes from the cheap FY3224S, it is very satisfactory.

Thanks again.

[ptluis]

About the DC calibration I only adjusted the positive DC. I adjusted the Mean measurement of the scope to be as close as possible to the DC signal Voltage, i also used a multimeter in this case UT61E at same time to certify the correct DC value. you can adjust Vpp or DC independently. I was able to adjust each value with a precision of 2 digits in the mV range. But of course this is a cheap scope and may occur some deviation when it's not operated in ideal temp, but anyway it's according to specs. It's not a multimeter but it's enough for many task and I can save my good equipment in situations where a mistake could blow it.

Yes.
After some fiddling, I am happy now. 
The effort with the upgrade was worth it.
Attached are a few examples: 50mV, 100mV, 500mV, 5V, 20V (Roughly, the SG has steps), and DC: +2V, +3V, +5V.
Considering that the signal comes from the cheap FY3224S, it is very satisfactory.

Thanks again.

That's really nice! as you see it was not to difficult when we know how to do.it. It worth the time spent.
The values look nice, and the small difference between Ch1 and Ch2 also happens on mine,  So no big deal. For a cheap scope it behaves real good 👍 and the manual calibrations of the measurements is a must have!

Thanks for sharing the photos of all steps. That's what I should have done, but I'm out of time, have a deadline on the actual job.

[Aldo22]

I took a look at the zoom feature.
Yes, it's a gadget and unfinished.
I didn't crash it though (Didn't try to).

As I figured, it's not that useful.
It may be a somewhat useful to "navigate" through non-repetitive signals.

Good luck with your job!

[ptluis]

I took a look at the zoom feature.
Yes, it's a gadget and unfinished.
I didn't crash it though (Didn't try to).

As I figured, it's not that useful.
It may be a somewhat useful to "navigate" through non-repetitive signals.

Good luck with your job!

Check if your scope freeze/crash following this steps:
with your scope in OFF state

1. remove probes
2. Turn ON scope, wait for boot to complete
3. set horizontal timebase to 200us
4. Long press "s" key to enter zoom mode
5. Press AUTO
6. Keep short pressing "s" key to zoom out until scoope freezes and crash (arround 500us)

 This is one of many ways to crash the scope. Solution is to never press AUTO in zoom mode

[timschuerewegen]

I am considering to buy this oscilloscope to analyze ~1MHz digital/analog LCD signals.

The manual says "in stop mode, the user can move the waveform left and right".

How far can I move the waveform left and right in stop mode when the timebase is set to 1us? In other words, how much captured data can I view/analyze that way? 14us? 15us? 16us? ...

Would the DPOX180H be better suited for this use case?

Thanks.

[Aldo22]

In zoom mode you can get an idea of this.
What you see in the lower part corresponds to the dark section above.
I hope it helps.

[csuhi17]

DPOX180H is what you see at the moment of recording, there is no data to the right or left.
A maximum of 25K points have gone down on the display.
The zoom function does not give better resolution.

[battlecoder]

I'm compiling a list of  key combinations not shown in the Menus or indicated above the keys (Some are documented in the manual, others are not). My idea is to print this on a card and put it inside the oscilloscope case as a cheat sheet. If you know of any combination I'm missing please let me know.

<MENU> : Has to be done inside this menu
((KEY)): Hold down for a couple of seconds

High Refresh Rate	<Disp> ((Run|Stop))
XY Mode	Power + OK
Check version	<Set> ((V))
Direct Trigger Level Adj	Power + 🡄 / 🡆
Zoom Mode	((s))
Overclock Mode	<Aux> ((🡅))
Normal Clock Mode	<Aux> ((🡇))
Freeze Wave As Reference	((F1))
Measurement Background Color	<Set> ((s))
USB Connection Mode	<Set> ((ns))
Reset Osc. Settings	<Set> ((Auto))
Grid On/Off	<Set> ((mV))
TV Output	<Set> ((Run|Stop))
DC Offset Calibration	<Meas> Press "CH1/CH2" then ((V))             Use 🡅/🡇 to calibrate CH1. 🡄/🡆 for CH2.             Must be done for every vertical scale.
AC Gain Calibration	<Meas> Press CH1/CH2 then ((mV))             Use 🡅/🡇 to calibrate CH1. 🡄/🡆 for CH2.

Keep in mind that Zoom and Calibration modes are only available in firmware 1.2.8C+
ALSO, Changing the measurement background is a bit more annoying in that version of the firmware, because every time you keep "s" pressed, even inside a menu, the zoom mode will kick in. So you need to long-press "s" again to disable the zoom mode AND change the background color from inside the menu.

It would be great if Zeeweii would fix this, so once you are inside a menu long-pressing "s" doesn't toggle zoom mode.

EDIT:
I was casually looking into calibration-related posts in this thread, and discovered that Aldo22 had already made a great cheatsheet that is pretty much exactly what I had in mind  . I'm keeping my post because unlike the PDF I guess this post is "searchable" and will lead people to Aldo22's great work.

[ptluis]

Keep in mind that Zoom and Calibration modes are only available in firmware 1.2.8C+
ALSO, Changing the measurement background is a bit more annoying in that version of the firmware, because every time you keep "s" pressed, even inside a menu, the zoom mode will kick in. So you need to long-press "s" again to disable the zoom mode AND change the background color from inside the menu.

It would be great if Zeeweii would fix this, so once you are inside a menu long-pressing "s" doesn't toggle zoom mode.

You just have to live with that or downgrade to the stock version v1.2.8C that I included in the zip file, and loose of course, the ability to manual calibrate the scope, and the zoom feature although buggy and incomplete it could be useful in same situations. Zeeweii won't fix that, they won't work on this firmware for the near future. They collect suggestions to release new products, just like most of the manufacturers of this low cost devices do.

[Aldo22]

EDIT:
I was casually looking into calibration-related posts in this thread, and discovered that Aldo22 had already made a great cheatsheet that is pretty much exactly what I had in mind  . I'm keeping my post because unlike the PDF I guess this post is "searchable" and will lead people to Aldo22's great work.

Thanks, that reminded me to update the cheat sheet.

By the way, there is also a graphically designed cheat sheet by Old man 45.

[timschuerewegen]

Thanks. I ordered one. I am probably going to hack/modify the firmware, to make it look nicer.

In zoom mode you can get an idea of this.
What you see in the lower part corresponds to the dark section above.
I hope it helps.