New toy(?) scope Fnirsi DPOX180H, claimed 180MHz/500MSps (May 2023)

[PA4TIM]

All my DSO's remember the last setting, That saves me a lot of time. I often make measurements that need a lot of settings. My serious scopes are the 60 MHz Siglent SHS1062 scopemeter and my 300 MHz R&S RTB2004, also the R&S 350 MHz scope I had before (can not remember the type-number)

But I have a "low budget" (compared to real scopes, not to useless graphical indicator toys  )  scope-meter, the CEM DT9989 this one does not remember the settings but I do not mind because I do not use it a lot. Just a handy compact thing I can take with me. If I know upfront I need a scope outside the lab I take the Siglent.

[ptluis]

would be like this, CH2

thanks ru_tash for the example.  it really is a strange way of using cursors, they should modify this function and make it similar to what we are used to.  it's a shame to operate this way because this little device could be a best seller in this price range.  if fnirsi reads these posts it should follow the advice of those who use oscilloscopes.  I'm suspending purchases for now until I see if fnirsi decides to improve this function.

[Rooster Cogburn]

if fnirsi reads these posts it should follow the advice of those who use oscilloscopes.  I'm suspending purchases for now until I see if fnirsi decides to improve this function.

Seems like they accept suggestions & bug reports by messaging their AliExpress store?

[ptluis]

if fnirsi reads these posts it should follow the advice of those who use oscilloscopes.  I'm suspending purchases for now until I see if fnirsi decides to improve this function.

Seems like they accept suggestions & bug reports by messaging their AliExpress store?

I already sent them a message through AliExpress page.

I have found a new video showing a new bug/crash of this device when using the usb function. Try on your units to see if it happens.
https://youtu.be/NLNTrn9KVrk

[RAPo]

I don't think this will be solved. The developers state it is working as described in the manual (which indeed it is).
I've had several conversations with them and the version 2 software only made a clearer indication on the screen, but no change of functionality.

would be like this, CH2

thanks ru_tash for the example.  it really is a strange way of using cursors, they should modify this function and make it similar to what we are used to.  it's a shame to operate this way because this little device could be a best seller in this price range.  if fnirsi reads these posts it should follow the advice of those who use oscilloscopes.  I'm suspending purchases for now until I see if fnirsi decides to improve this function.

[RAPo]

I also had several messages sent to them.
Never had the USB lockup.

if fnirsi reads these posts it should follow the advice of those who use oscilloscopes.  I'm suspending purchases for now until I see if fnirsi decides to improve this function.

Seems like they accept suggestions & bug reports by messaging their AliExpress store?

I already sent them a message through AliExpress page.

I have found a new video showing a new bug/crash of this device when using the usb function. Try on your units to see if it happens.
https://youtu.be/NLNTrn9KVrk

[ru_tash]

would be like this, CH2

thanks ru_tash for the example.  it really is a strange way of using cursors, they should modify this function and make it similar to what we are used to.  it's a shame to operate this way because this little device could be a best seller in this price range.  if fnirsi reads these posts it should follow the advice of those who use oscilloscopes.  I'm suspending purchases for now until I see if fnirsi decides to improve this function.

I would not call Fnirsi DPOX180H as device for measurement, it is more like for signal evaluation, so cursor function is just to help you not to move finger along the grid on screen counting intervals.

look at the attachments: I measure lithium battery with both polarity, and result not as expected. Vp and Vmax not equal for + and - connections. The real voltage of battery 4.09V

[Evi]

I wrote my suggestions to fnirsiofficialcs@gmail.com
and now got an answer:


> Hi, Dear friend; Thank you very much for your suggestion;
> 1. Can the current settings be saved automatically when the power is turned
> off? ----Need to save settings in settings.
> 2. Internal generator has significant DC offset. Are you going to delete
> it? --------- Technicians are trying to fix it.
> 3. The firmware version cannot be checked in the current firmware (3.0).
> Maybe show it on the splash screen? ----------I will mention this plan to
> the technical staff;
>
> You can follow our official website;
> http://www.fnirsi.cn/support
> If there is a new plan; we will post it above;
> have good day!
> by Fnirsi

[Aldo22]

I guess you could place one cursor on 0?

You can always find a workaround, why not measure with a ruler? 

Imo they started this wrong.
They should not attempt to display cursor information for both channels at the same time on a small screen.
That's probably why they left out the Y1_1, Y2_1, Y1_2, Y2_2 because the screen was getting too crowded.
The cursor box on the Zeeweii is also a bit large/full, but at least it only contains the measurements for the selected channel (See yellow/green in the attached image).

[RAPo]

agreed.

[ptluis]

I don't think this will be solved. The developers state it is working as described in the manual (which indeed it is).
I've had several conversations with them and the version 2 software only made a clearer indication on the screen, but no change of functionality.

would be like this, CH2

thanks ru_tash for the example.  it really is a strange way of using cursors, they should modify this function and make it similar to what we are used to.  it's a shame to operate this way because this little device could be a best seller in this price range.  if fnirsi reads these posts it should follow the advice of those who use oscilloscopes.  I'm suspending purchases for now until I see if fnirsi decides to improve this function.

well if fnirsi don't improve this product it will definitely looks like an unfinished project for school. If they follow this topic like they said on the replied email, they will create a product that could stop being a toy to view colors. At this moment we also need to buy some extras like a calculator and a ruler  , or we can save some money and start doing the math by hand...

[Rooster Cogburn]

You can always find a workaround, why not measure with a ruler? 

Imo they started this wrong.

I agree completely, what they did is a bad choice since it's super confusing initially and still awkward when you get what they're doing.

look at the attachments: I measure lithium battery with both polarity, and result not as expected. Vp and Vmax not equal for + and - connections. The real voltage of battery 4.09V

Hm, I wonder how this could possibly be so wrong. The same thing happens when you just measure your bench PSU, even with a longer timebase?

[RAPo]

..  At this moment we also need to buy some extras like a calculator and a ruler  , or we can save some money and start doing the math by hand...

well you could save it as a .wav file, go to the right offset and look for the measured values (see this post).

[BillyO]

Has anyone verified the bandwidth of these yet?  I've seen references like "go back and read my 300 posts, it's in there somewhere".  I did that, but must have blinked because I did not see a plain and direct statement of measured bandwidth.  Can anyone let me know?

[RAPo]

Did the same test but with my Owon 3033 power supply.
Indeed a difference if the polarity is reversed.

I guess you could place one cursor on 0?

You can always find a workaround, why not measure with a ruler? 

Imo they started this wrong.
They should not attempt to display cursor information for both channels at the same time on a small screen.
That's probably why they left out the Y1_1, Y2_1, Y1_2, Y2_2 because the screen was getting too crowded.
The cursor box on the Zeeweii is also a bit large/full, but at least it only contains the measurements for the selected channel (See yellow/green in the attached image).

[Rooster Cogburn]

That's really interesting, I wonder what causes this bug and what support says about this

[Aldo22]

Do not exaggerate.
An oscilloscope is not a multimeter.
DC accuracy is +- 2%, so that's still within tolerance.
Zeeweii had a similar problem and I guess it is fixed in the latest versions.
Read the comment from 25 Apr 2023: "Arrived to Kyiv in 23 days..."
https://de.aliexpress.com/item/1005003085753955.html

Btw: Isn't there a measurement type called "AVG" or something like that?
The Zeeweii has "Mean" for DC measurement.

[RAPo]

I'm okay with not presenting exact numbers. But not changing polarity to different numbers (even in spec).
There is a measurement called V-avg. Will test this later.

[RAPo]

This post gives a statement that I concur with.

[ru_tash]

Do not exaggerate.
An oscilloscope is not a multimeter.
DC accuracy is +- 2%, so that's still within tolerance.
Zeeweii had a similar problem and I guess it is fixed in the latest versions.
Read the comment from 25 Apr 2023: "Arrived to Kyiv in 23 days..."
https://de.aliexpress.com/item/1005003085753955.html

Btw: Isn't there a measurement type called "AVG" or something like that?
The Zeeweii has "Mean" for DC measurement.

From Kyiv guy: "He sent me a file with new firmware and detailed instructions for installing it and additional calibration of the device"
That is good for Zeeweii, let's see if Fnirsi will not hide similar instructions for his consumers.

By the way, I discovered that measurements get more or less acceptable if to turn-off another channel.

[RAPo]

V avg gives a bit better results.

[Evi]

Bravo!
Precision measuring DC voltage with oscilloscope is a new achivement in a world of measurements!

Maniacs, try this with serious scopes and observe the same results.

[dietert1]

Doesn't the DPOX180H include a DVM? I mean for DC i normally use a DVM if i want some accuracy.

Regards, Dieter

[Rooster Cogburn]

Bravo!
Precision measuring DC voltage with oscilloscope is a new achivement in a world of measurements!

Maniacs, try this with serious scopes and observe the same results.

The lack of absolute correctness or the difference when reversing polarity? The former seems absolutely fine to me, but the latter strikes me as off.

Doesn't the DPOX180H include a DVM? I mean for DC i normally use a DVM if i want some accuracy.

Nope!

---

Another question:

I was looking again at similarly priced scopes and was wondering if there's anything around the hundred bucks mark that includes any protocol decoding?

[RAPo]

As stated multiple times above: we are not in a race to measure voltages to x-digit precision with an oscilloscope.
We are exploring how the oscilloscope reacts in different test circumstances ie switching polarity.
If a forum user asks if there is something like avg, people are helping out and present results.
So why  this kind of tone in your post?

Bravo!
Precision measuring DC voltage with oscilloscope is a new achivement in a world of measurements!

Maniacs, try this with serious scopes and observe the same results.