Author Topic: Siglent SDS1104X-E anomaly on what should be a simple task.  (Read 6205 times)

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Online 2N3055

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Re: Siglent SDS1104X-E anomaly on what should be a simple task.
« Reply #25 on: November 05, 2022, 01:15:42 pm »
You posted a link to this from one of my threads and I agree your situation is terrible, the pictures show a stark contrast.

What do you think of a Rigol DS1052E?

I'm after a digital one to capture things that don't repeat and I'm not asking for recommendations as such, I'm asking "is it afflicted by the same deal breaking problem?"


Or was yours somehow defective? The probes perhaps?


Thanks

There is no problem. Whole signal should fit on a screen. If you have something going off the screen then your signal is out of dynamic range of that particular input settings.
That means you're overdriving something and will be at mercy of overdrive recovery.

To be honest, there will be a little area of the screen where it still works but it is not 5 screens high more like 10%.

So simple rule that works all the time: your whole signal amplitude should fit vertically on screen.
 

Offline bdunham7Topic starter

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Re: Siglent SDS1104X-E anomaly on what should be a simple task.
« Reply #26 on: November 06, 2022, 05:43:36 am »
Or was yours somehow defective? The probes perhaps?

It wasn't defective, it simply has a characteristic of having much, much slower overdrive recovery than the other scopes I compared it to.  It has been stated by others that this is simply the nature of modern DSO input amplifiers, but I haven't taken the time to compare any others nor do I actually have access to many to try.  AFAIK nobody has tried my fairly simple signal test on any fancier scopes.  It is possible that older designs may not have this issue even in cheapo scopes, but I don't know. 

Yes, keeping the signal on the screen fixes the issue, or at least almost does (there was a thread about this same scope showing a small dip on a very slow square wave and I think that is probably also related to the damping of the input amplifier somehow) but keeping it on the screen also reduces the resolution of your view of the signal that you actually want to see.
A 3.5 digit 4.5 digit 5 digit 5.5 digit 6.5 digit 7.5 digit DMM is good enough for most people.
 

Online 2N3055

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Re: Siglent SDS1104X-E anomaly on what should be a simple task.
« Reply #27 on: November 06, 2022, 10:37:34 am »
I'm sorry I don't know the links of top of my head (and won't be searching for it), but modern DSO scopes have more limited dynamic range than old CRT scopes. Members here did find that some old Tek DSO had a bit better overdrive behaviour but not much.
I tried with Keysight 3000T, people tried with R&S scopes and they all have overdrive recovery distortions (R&S RTB2000 and RTM3000 quite nasty ones too). Also I remember RTB2000 had squarewave droop on some timebases on some scopes, it was on here few weeks ago..

AFAIK nobody has tried my fairly simple signal test on any fancier scopes.  It is possible that older designs may not have this issue even in cheapo scopes, but I don't know. 

Would you be so kind and remind me as to what test you mean? Thanks.
 

Offline bdunham7Topic starter

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Re: Siglent SDS1104X-E anomaly on what should be a simple task.
« Reply #28 on: November 06, 2022, 02:24:17 pm »
Would you be so kind and remind me as to what test you mean? Thanks.

This one here:

https://www.eevblog.com/forum/testgear/siglent-sds1104x-e-anomaly-on-what-should-be-a-simple-task/msg3451402/#msg3451402

Quote
Members here did find that some old Tek DSO had a bit better overdrive behaviour but not much.

My Tek 2221A CRO/DSO hybrid did fine, but my Tek TPS2024 also seems to recover quickly enough to not have issues with this test.  Since the recent poster asked about the Rigol 1052E, I have to wonder if it might actually be OK here--it has the same analog trigger circuitry (well, not quite) and pitifully small memory as the TPS2024.   Looking at the thread again and in light of the more recent discussion regarding the 'dip' on a 10Hz square wave, I think there is visible distortion even on the first screenshot with the signal fully on the screen.  I think there is more than just overdrive recovery going on there.

Edit:  One additional data point--I just tried the SDS2104X+ on this test, it works fine down to 200mV/div, (15 divisions off the top of the screen) but fails below that. 
« Last Edit: November 06, 2022, 03:00:32 pm by bdunham7 »
A 3.5 digit 4.5 digit 5 digit 5.5 digit 6.5 digit 7.5 digit DMM is good enough for most people.
 

Online 2N3055

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Re: Siglent SDS1104X-E anomaly on what should be a simple task.
« Reply #29 on: November 06, 2022, 04:17:39 pm »
Would you be so kind and remind me as to what test you mean? Thanks.

This one here:

https://www.eevblog.com/forum/testgear/siglent-sds1104x-e-anomaly-on-what-should-be-a-simple-task/msg3451402/#msg3451402

Quote
Members here did find that some old Tek DSO had a bit better overdrive behaviour but not much.

My Tek 2221A CRO/DSO hybrid did fine, but my Tek TPS2024 also seems to recover quickly enough to not have issues with this test.  Since the recent poster asked about the Rigol 1052E, I have to wonder if it might actually be OK here--it has the same analog trigger circuitry (well, not quite) and pitifully small memory as the TPS2024.   Looking at the thread again and in light of the more recent discussion regarding the 'dip' on a 10Hz square wave, I think there is visible distortion even on the first screenshot with the signal fully on the screen.  I think there is more than just overdrive recovery going on there.

Edit:  One additional data point--I just tried the SDS2104X+ on this test, it works fine down to 200mV/div, (15 divisions off the top of the screen) but fails below that. 

Thanks fo the link. Yes these kinds of tests were done, and I cannot remember where exactly I posted this (there were dozens of these discussions on same topic over years) but pretty much all modern scopes (designed in the last 10ish years) will have same problem. R&S RTB2000/RTM3000 has really bad response to overdrive, my Keysight 3000T also.
There is a bit of range outside screen but maybe 10-20% (it will vary on input range , sometimes a bit more) and only way to do it right is to keep it on the screen. Inside signal path uses low voltage rails and if you apply 1 volt to input of amplifier with 20X gain that drives amp into clipping. Simple as that.
Even old CRT scopes had same problem, but they had very high voltages inside and therefore large dynamic headroom. Also they have been optimized for such use because with analog scopes you had to look at signal differently...

Vertical offset works to nullify large DC from signal that has large DC with some AC on top. In which case you subtract DC part and amplifier gets only the rest. You could do that with AC coupling, but DC coupling with offset retains absolute voltage values for correct measurements.
Different scopes have different DC offset ranges. One thing I like about SDS2000X HD is extended offset in comparison to other scopes in class.. Useful for work on power circuits, well complemented with 12 bit, low noise and analysis package..
 

Offline mawyatt

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Re: Siglent SDS1104X-E anomaly on what should be a simple task.
« Reply #30 on: November 06, 2022, 04:27:51 pm »

Vertical offset works to nullify large DC from signal that has large DC with some AC on top. In which case you subtract DC part and amplifier gets only the rest. You could do that with AC coupling, but DC coupling with offset retains absolute voltage values for correct measurements.
Different scopes have different DC offset ranges. One thing I like about SDS2000X HD is extended offset in comparison to other scopes in class.. Useful for work on power circuits, well complemented with 12 bit, low noise and analysis package..

Exactly!! The DC Offset is very beneficial when one doesn't want the low corner of the AC coupling to alter the signal of interest. The SDS2000X+ also has a nice wide DC Offset range that is stable and doesn't add noise!!

Does the HD version have a wider DC Offset range than the X+ ?

Best,
Curiosity killed the cat, also depleted my wallet!
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Online 2N3055

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Re: Siglent SDS1104X-E anomaly on what should be a simple task.
« Reply #31 on: November 06, 2022, 04:52:51 pm »

Vertical offset works to nullify large DC from signal that has large DC with some AC on top. In which case you subtract DC part and amplifier gets only the rest. You could do that with AC coupling, but DC coupling with offset retains absolute voltage values for correct measurements.
Different scopes have different DC offset ranges. One thing I like about SDS2000X HD is extended offset in comparison to other scopes in class.. Useful for work on power circuits, well complemented with 12 bit, low noise and analysis package..

Exactly!! The DC Offset is very beneficial when one doesn't want the low corner of the AC coupling to alter the signal of interest. The SDS2000X+ also has a nice wide DC Offset range that is stable and doesn't add noise!!

Does the HD version have a wider DC Offset range than the X+ ?

Best,

Hi Mike,

it does, quite more:
------------------------------------------
SDS2000X+ :

Offset range (probe 1X)
500 μV/div ~ 100 mV/div: ± 2 V
102 mV/div ~ 1 V/div: ± 20 V
1.02 V/div ~ 10 V/div: ± 200 V
------------------------------------------
SDS2000X HD
Offset range (probe 1X)

1 MΩ:
0.5 mV/div ~ 5 mV/div: ±1.6 V;
5.1 mV/div ~ 10 mV/div: ±4 V;
10.2 mV/div ~ 20 mV/div:±8 V;
20.5 mV/div ~ 100 mV/div: ±16 V;
102 mV/div ~ 200 mV/div: ±80 V;
205 mV/div ~ 1 V/div: ±160 V;
1.02 V/div ~ 10 V/div: ±400 V

50 Ω:
0.5 mV/div ~ 5 mV/div: ±1.6V;
5.1 mV/div ~ 10 mV/div: ±4 V;
10.2 mV/div ~ 20 mV/div:±8 V;
20.5 mV/div ~ 1 V/div: ±10 V

Take care!
 
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Offline mawyatt

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Re: Siglent SDS1104X-E anomaly on what should be a simple task.
« Reply #32 on: November 07, 2022, 02:45:08 pm »

Hi Mike,

it does, quite more:
------------------------------------------
SDS2000X+ :

Offset range (probe 1X)
500 μV/div ~ 100 mV/div: ± 2 V
102 mV/div ~ 1 V/div: ± 20 V
1.02 V/div ~ 10 V/div: ± 200 V
------------------------------------------
SDS2000X HD
Offset range (probe 1X)

1 MΩ:
0.5 mV/div ~ 5 mV/div: ±1.6 V;
5.1 mV/div ~ 10 mV/div: ±4 V;
10.2 mV/div ~ 20 mV/div:±8 V;
20.5 mV/div ~ 100 mV/div: ±16 V;
102 mV/div ~ 200 mV/div: ±80 V;
205 mV/div ~ 1 V/div: ±160 V;
1.02 V/div ~ 10 V/div: ±400 V

50 Ω:
0.5 mV/div ~ 5 mV/div: ±1.6V;
5.1 mV/div ~ 10 mV/div: ±4 V;
10.2 mV/div ~ 20 mV/div:±8 V;
20.5 mV/div ~ 1 V/div: ±10 V

Take care!

I thought the SDS2000X+ had a very good DC Offset range, the HD version is indeed outstanding :-+

Thanks for the quick reply, and the usual quality information  :clap:

Best,
Curiosity killed the cat, also depleted my wallet!
~Wyatt Labs by Mike~
 
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Offline py-bb

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Re: Siglent SDS1104X-E anomaly on what should be a simple task.
« Reply #33 on: December 27, 2022, 04:27:06 am »
Or was yours somehow defective? The probes perhaps?

It wasn't defective, it simply has a characteristic of having much, much slower overdrive recovery than the other scopes I compared it to.  It has been stated by others that this is simply the nature of modern DSO input amplifiers, but I haven't taken the time to compare any others nor do I actually have access to many to try.  AFAIK nobody has tried my fairly simple signal test on any fancier scopes.  It is possible that older designs may not have this issue even in cheapo scopes, but I don't know. 

Yes, keeping the signal on the screen fixes the issue, or at least almost does (there was a thread about this same scope showing a small dip on a very slow square wave and I think that is probably also related to the damping of the input amplifier somehow) but keeping it on the screen also reduces the resolution of your view of the signal that you actually want to see.

SOrry for the late reply, can you link me the tests you want to run? I can give them a go if I have the equipment.


One issue I've found with the DSO scopes around me (whether it generalises I can't say) is that if you use a voltage offset they get bad.

I am 99.9% sure that internally the ones around me amplify/attenuate/buffer the input so it is in the range -1v to +1v for the scale on the settings.

When I apply an offset and get above 70% of the range I can offset the edge of a square wave becomes really curved, it doesn't undershoot, it's just much slower - I'll take some screenshots later if it'll help.

What I'll try doing is adding a DC offset to a square wave that is in range and see if it persists.
 

Offline tautech

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Re: Siglent SDS1104X-E anomaly on what should be a simple task.
« Reply #34 on: December 27, 2022, 06:45:19 am »

One issue I've found with the DSO scopes around me (whether it generalises I can't say) is that if you use a voltage offset they get bad.
See Offset Range (Probe 1X) P8 in Datasheet:
https://int.siglent.com/u_file/document/SDS1000X-E_DataSheet_EN04D.pdf

Yep show us some screenshots.
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Offline py-bb

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Re: Siglent SDS1104X-E anomaly on what should be a simple task.
« Reply #35 on: December 27, 2022, 07:24:24 am »

One issue I've found with the DSO scopes around me (whether it generalises I can't say) is that if you use a voltage offset they get bad.
See Offset Range (Probe 1X) P8 in Datasheet:
https://int.siglent.com/u_file/document/SDS1000X-E_DataSheet_EN04D.pdf

Yep show us some screenshots.

I've literally just put that away. I've got an older LeCroy to hand I'll take screenshots in a bit. I've not tried the DC offset thing before, but I have tried adjusting the offset, the more extreme the offset the slower the rise time on the square wave is - this is just "panning" around on the calibrate hook.

It's an extreme effect and I do wonder how it works to generate it, I imagined it'd generate a voltage and feed that into an op-amp, that's what makes me think saturation could be in play.
 

Offline py-bb

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Re: Siglent SDS1104X-E anomaly on what should be a simple task.
« Reply #36 on: December 27, 2022, 07:29:43 am »

One issue I've found with the DSO scopes around me (whether it generalises I can't say) is that if you use a voltage offset they get bad.
See Offset Range (Probe 1X) P8 in Datasheet:
https://int.siglent.com/u_file/document/SDS1000X-E_DataSheet_EN04D.pdf

Yep show us some screenshots.

Okay it wasn't with the calibration port. I was using a function generator (but not changing the output just "panning" the waveform) - will definitely do it just to figure out what it's called, but not now sorry. Either in the next hour or two or tomorrow.
 

Online Performa01

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Re: Siglent SDS1104X-E anomaly on what should be a simple task.
« Reply #37 on: December 27, 2022, 10:33:17 am »
The topic of overload recovery pops up over and over again, and still doesn't seem to be understood by everyone (for instance it has nothing to do with semiconductor switching times or something like this) and it certainly can't be a deal breaker.

I've tried to explain the issue several times, the last one was reply #41 here:

https://www.eevblog.com/forum/testgear/rtb2004-still-worth-it-in-2021/msg3788153/#msg3788153

What I would like to add: A higher input offset compensation range in these split path input buffers will also result in worse input overload recovery beaviour.
 
 

Offline py-bb

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Re: Siglent SDS1104X-E anomaly on what should be a simple task.
« Reply #38 on: December 28, 2022, 11:58:25 am »
Okay I did the experiment.

First up the full wave we're viewing. There is a 50 ohm terminator in play (as with the DC offset the scope kept overloading and tripping)

1673830-0

As you can see not a bad square, the rise is pretty good.

1673836-1

Okay now we view the top - hmm... that wasn't there before.

1673842-2

In this picture I've added a positive DC offset which the square wave is on top of, as a result the square wave's amplitude is lower, as you can see - it's a lot less bad.

It's a pretty bad artifact. According to the service manual it's just a DC bias into an op-amp.

Great that those attachments didn't work when it did it that way.

BTW this is an extreme example, I had it at 6.84v offset (maxes out at 10) so it's not "terribly far" and a frighteningly large artifact but when viewing something riding on an offset that's nearby it's OK, so as long as the signal's "within view" it tends to be good.

There's a person here saying "oh that's expected behaviour" https://www.eevblog.com/forum/testgear/siglent-sds1104x-e-anomaly-on-what-should-be-a-simple-task/?action=dlattach;attach=1167288;image - this image is not. That's terrible! I agree with OP here and is on screen!

You need to trust the scope to reproduce a signal that fits in the range accurately, there's no excuse for that!
« Last Edit: December 28, 2022, 12:15:23 pm by py-bb »
 

Online 2N3055

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Re: Siglent SDS1104X-E anomaly on what should be a simple task.
« Reply #39 on: December 28, 2022, 02:00:33 pm »
Okay I did the experiment.

First up the full wave we're viewing. There is a 50 ohm terminator in play (as with the DC offset the scope kept overloading and tripping)

(Attachment Link)

As you can see not a bad square, the rise is pretty good.

(Attachment Link)

Okay now we view the top - hmm... that wasn't there before.

(Attachment Link)

In this picture I've added a positive DC offset which the square wave is on top of, as a result the square wave's amplitude is lower, as you can see - it's a lot less bad.

It's a pretty bad artifact. According to the service manual it's just a DC bias into an op-amp.

Great that those attachments didn't work when it did it that way.

BTW this is an extreme example, I had it at 6.84v offset (maxes out at 10) so it's not "terribly far" and a frighteningly large artifact but when viewing something riding on an offset that's nearby it's OK, so as long as the signal's "within view" it tends to be good.

There's a person here saying "oh that's expected behaviour" https://www.eevblog.com/forum/testgear/siglent-sds1104x-e-anomaly-on-what-should-be-a-simple-task/?action=dlattach;attach=1167288;image - this image is not. That's terrible! I agree with OP here and is on screen!

You need to trust the scope to reproduce a signal that fits in the range accurately, there's no excuse for that!

Do you plan to actually read what people answered and explained to you?

You are overloading scope input amplifiers by several order of magnitude. Distortion you see is caused by user insisting on doing what people are telling you is wrong.

ALL of your signal has to be on screen. If you have 100 mV P-P riding on top of 10V DC offset, you can set scope to 20mv/div, set offset for 10V (if scope has that offset in that range) and nicely see signal on the screen.
Because setting offset subtracted 10V DC component form the signal and you defacto have a 100mV P-P signal left for scope to analyse.

If you put in 10V P-P into scope set to 20mv/div and use scope offset to look at top level of signal, you are shoveling 10V signal in preamp set for 800mV full range... You get overdrive....

So in short, ifm when you are setting the scope, some part of signal goes under or over visible screen, you are doing it wrong.... signal has to enter the screen from the left, and exit to the right and never go outside top or bottom. It actually can, 10-20% more but that is it...

Once you accept that, I am willing to explain why is it so. And yes, all current digital scopes,cheapest to very expensive,  from all brands do this same very thing.

« Last Edit: December 28, 2022, 02:14:11 pm by 2N3055 »
 

Offline py-bb

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Re: Siglent SDS1104X-E anomaly on what should be a simple task.
« Reply #40 on: December 28, 2022, 02:22:49 pm »
Okay I did the experiment.

First up the full wave we're viewing. There is a 50 ohm terminator in play (as with the DC offset the scope kept overloading and tripping)

(Attachment Link)

As you can see not a bad square, the rise is pretty good.

(Attachment Link)

Okay now we view the top - hmm... that wasn't there before.

(Attachment Link)

In this picture I've added a positive DC offset which the square wave is on top of, as a result the square wave's amplitude is lower, as you can see - it's a lot less bad.

It's a pretty bad artifact. According to the service manual it's just a DC bias into an op-amp.

Great that those attachments didn't work when it did it that way.

BTW this is an extreme example, I had it at 6.84v offset (maxes out at 10) so it's not "terribly far" and a frighteningly large artifact but when viewing something riding on an offset that's nearby it's OK, so as long as the signal's "within view" it tends to be good.

There's a person here saying "oh that's expected behaviour" https://www.eevblog.com/forum/testgear/siglent-sds1104x-e-anomaly-on-what-should-be-a-simple-task/?action=dlattach;attach=1167288;image - this image is not. That's terrible! I agree with OP here and is on screen!

You need to trust the scope to reproduce a signal that fits in the range accurately, there's no excuse for that!

Do you plan to actually read what people answered and explained to you?

You are overloading scope input amplifiers by several order of magnitude. Distortion you see is caused by user insisting on doing what people are telling you is wrong.

ALL of your signal has to be on screen. If you have 100 mV P-P riding on top of 10V DC offset, you can set scope to 20mv/div, set offset for 10V (if scope has that offset in that range) and nicely see signal on the screen.
Because setting offset subtracted 10V DC component form the signal and you defacto have a 100mV P-P signal left for scope to analyse.

If you put in 10V P-P into scope set to 20mv/div and use scope offset to look at top level of signal, you are shoveling 10V signal in preamp set for 800mV full range... You get overdrive....

So in short, ifm when you are setting the scope, some part of signal goes under or over visible screen, you are doing it wrong.... signal has to enter the screen from the left, and exit to the right and never go outside top or bottom. It actually can, 10-20% more but that is it...

Once you accept that, I am willing to explain why is it so. And yes, all current digital scopes,cheapest to very expensive,  from all brands do this same very thing.

Your tone is somewhat twatish there and I must point out:

Did you see the picture linked? it is entirely on the screen!

As for my screenshots, I was asked to provide them and yes we already agreed it was saturation.

Finally: there's one difference between OP and I - mine rises quickly *then drops* then rises back up.

saying real world things are not ideal (no matter how twatty or twat-free the tone isn't helpful.
 

Online 2N3055

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Re: Siglent SDS1104X-E anomaly on what should be a simple task.
« Reply #41 on: December 28, 2022, 03:10:01 pm »
Okay I did the experiment.

First up the full wave we're viewing. There is a 50 ohm terminator in play (as with the DC offset the scope kept overloading and tripping)

(Attachment Link)

As you can see not a bad square, the rise is pretty good.

(Attachment Link)

Okay now we view the top - hmm... that wasn't there before.

(Attachment Link)

In this picture I've added a positive DC offset which the square wave is on top of, as a result the square wave's amplitude is lower, as you can see - it's a lot less bad.

It's a pretty bad artifact. According to the service manual it's just a DC bias into an op-amp.

Great that those attachments didn't work when it did it that way.

BTW this is an extreme example, I had it at 6.84v offset (maxes out at 10) so it's not "terribly far" and a frighteningly large artifact but when viewing something riding on an offset that's nearby it's OK, so as long as the signal's "within view" it tends to be good.

There's a person here saying "oh that's expected behaviour" https://www.eevblog.com/forum/testgear/siglent-sds1104x-e-anomaly-on-what-should-be-a-simple-task/?action=dlattach;attach=1167288;image - this image is not. That's terrible! I agree with OP here and is on screen!

You need to trust the scope to reproduce a signal that fits in the range accurately, there's no excuse for that!

Do you plan to actually read what people answered and explained to you?

You are overloading scope input amplifiers by several order of magnitude. Distortion you see is caused by user insisting on doing what people are telling you is wrong.

ALL of your signal has to be on screen. If you have 100 mV P-P riding on top of 10V DC offset, you can set scope to 20mv/div, set offset for 10V (if scope has that offset in that range) and nicely see signal on the screen.
Because setting offset subtracted 10V DC component form the signal and you defacto have a 100mV P-P signal left for scope to analyse.

If you put in 10V P-P into scope set to 20mv/div and use scope offset to look at top level of signal, you are shoveling 10V signal in preamp set for 800mV full range... You get overdrive....

So in short, ifm when you are setting the scope, some part of signal goes under or over visible screen, you are doing it wrong.... signal has to enter the screen from the left, and exit to the right and never go outside top or bottom. It actually can, 10-20% more but that is it...

Once you accept that, I am willing to explain why is it so. And yes, all current digital scopes,cheapest to very expensive,  from all brands do this same very thing.

Your tone is somewhat twatish there and I must point out:

Did you see the picture linked? it is entirely on the screen!

As for my screenshots, I was asked to provide them and yes we already agreed it was saturation.

Finally: there's one difference between OP and I - mine rises quickly *then drops* then rises back up.

saying real world things are not ideal (no matter how twatty or twat-free the tone isn't helpful.

Yes I'm a twat... Thank you... You are so kind. That comment definitely elevated this discussion.. Thank you.

This image ?

https://www.eevblog.com/forum/testgear/siglent-sds1104x-e-anomaly-on-what-should-be-a-simple-task/?action=dlattach;attach=1167288;image

What is wrong with it?



 

Offline py-bb

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Re: Siglent SDS1104X-E anomaly on what should be a simple task.
« Reply #42 on: December 28, 2022, 03:40:41 pm »
Twatish is bad..... but OK

You see where it changes and is all over the place - that's what wrong with it. I can't believe you consider that OK.
 

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Re: Siglent SDS1104X-E anomaly on what should be a simple task.
« Reply #43 on: December 28, 2022, 03:58:53 pm »
Twatish is bad..... but OK

You see where it changes and is all over the place - that's what wrong with it. I can't believe you consider that OK.

Thank you for being kind....

As for signal, that is how source signal looks. ...
 

Offline bdunham7Topic starter

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Re: Siglent SDS1104X-E anomaly on what should be a simple task.
« Reply #44 on: December 28, 2022, 10:32:00 pm »
As for signal, that is how source signal looks. ...

Pretty much--this was intended to be the 'good' example, but there is a small bit of settling after the large transition even with that screenshot with all of the signal on the screen.  I didn't think much of it at the time since it is so small, but there does appear to be a bit of damping/settling behavior at these slower timebases.  Others have remarked on a small 'dip' in slow square waves on this scope as well.
A 3.5 digit 4.5 digit 5 digit 5.5 digit 6.5 digit 7.5 digit DMM is good enough for most people.
 


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