Author Topic: Siglent SDS2000 new V2 Firmware  (Read 97769 times)

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Offline Wuerstchenhund

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Re: Siglent SDS2000 new V2 Firmware
« Reply #25 on: November 25, 2015, 07:53:57 pm »
OK, so I finally had a chance to give this new firmware a spin on my SDS2204. The latest v1 update was pretty much crap and the typical bugfest we've come to expect by now, so it ran the v2 beta which seemed to be more stable than the v1 mess, plus it has a much more logical UI (although there's still room for improvement).

It's of course great that Siglent has (for the first time!) kept its promise to come up with the v2 release firmware by the end of November  :-+ However, as with pretty much any firmware Siglent has come up with for the SDS2000, this one seems to suffer from silly bugs, too. I played with the scope for roughly an hour including the upgrade processes, and immediately found two.

The first one appeared after calling up the Acquisition menu, after which the waveform trace disappeared:



Any attempts to restore the trace failed, until I switched the scope off and on again.


The second one bug I found affects the trace offset at higher vertical sensitivity settings where the trace shifts vertically despite having a zero offset:











This is with open inputs, i.e. nothing connected. It doesn't matter if the termination is set to 1M, 50ohms or GND (actually, GND doesn't seem to do anything, but I haven't looked closer at it).

Reloading the firmware didn't help (I even tried the 2x reflash as in the manual, despite having upgraded from v2 beta), and a self-calibration didn't help, either. This is most certainly a bug in the firmware, but I don't have the scope long enough to know if this a new one or an old one that hasn't been fixed/has re-appeared.

Remember that I only played with the scope and the new firmware for less than an hour (and didn't even connect a signal) and immediately found two bugs, and I'm pretty sure that whenever the scope is used in anger that more bugs will surface. Not great for a product which is on the market for pretty much one and a half year.

So I guess the improvements are down to a slighlty better UI and more sample memory, but the scope seems to be still pretty much a bugfest   :--
« Last Edit: November 25, 2015, 08:05:40 pm by Wuerstchenhund »
 

Offline nctnico

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Re: Siglent SDS2000 new V2 Firmware
« Reply #26 on: November 25, 2015, 08:43:05 pm »
That DC shift may dissapear when you leave it on for a while (let it heat up properly). From the SDS2000 I had I recall it needed some warming up time (much more than a few minutes!) before the DC level of the trace got to 0.
« Last Edit: November 25, 2015, 08:45:50 pm by nctnico »
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Re: Siglent SDS2000 new V2 Firmware
« Reply #27 on: November 25, 2015, 09:45:28 pm »
I played with the scope for roughly an hour including the upgrade processes, and immediately found two.

The first one appeared after calling up the Acquisition menu, after which the waveform trace disappeared:
Any attempts to restore the trace failed, until I switched the scope off and on again.
Numerous attempts failed to reproduce this, anybody else seen this?


Quote
The second one bug I found affects the trace offset at higher vertical sensitivity settings where the trace shifts vertically despite having a zero offset

This is with open inputs, i.e. nothing connected. It doesn't matter if the termination is set to 1M, 50ohms or GND (actually, GND doesn't seem to do anything, but I haven't looked closer at it).
I see a small ofset too, ~60uV on the 1mV setting, mine looks less than yours.
If the Trigger level knob is pushed (set to 50%) the offset value will be displayed.

Here's a GND input coupled screenshot, other settings same as yours AFAICT.

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Offline Wuerstchenhund

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Re: Siglent SDS2000 new V2 Firmware
« Reply #28 on: November 25, 2015, 09:47:24 pm »
That DC shift may dissapear when you leave it on for a while (let it heat up properly). From the SDS2000 I had I recall it needed some warming up time (much more than a few minutes!) before the DC level of the trace got to 0.

I doubt it's the temperature, the scope was powered on for almost 45mins before I even started using it.
 

Online tautechTopic starter

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Re: Siglent SDS2000 new V2 Firmware
« Reply #29 on: November 27, 2015, 06:13:49 am »
Has anybody got any tweaks/additions needed for the V2 FW?
Bugs?

Siglent are watching this thread with interest.
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Offline jitter

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Re: Siglent SDS2000 new V2 Firmware
« Reply #30 on: November 27, 2015, 06:27:20 am »
That DC shift may dissapear when you leave it on for a while (let it heat up properly). From the SDS2000 I had I recall it needed some warming up time (much more than a few minutes!) before the DC level of the trace got to 0.

I doubt it's the temperature, the scope was powered on for almost 45mins before I even started using it.

SelfCal? I found my Rigol needed a self cal after upgrading the firmware, perhaps the same goes for this Siglent.
 

Offline cidcorp

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Re: Siglent SDS2000 new V2 Firmware
« Reply #31 on: November 27, 2015, 07:35:02 am »
Has anybody got any tweaks/additions needed for the V2 FW?
Bugs?

Siglent are watching this thread with interest.

I started to make a list, but then got side - tracked because of my Option serial Keys not working with the new firmware.
Still waiting for the person who was going to resend the keys to me. 

I haven't really checked this list over and it was what I started to see in the first  hours of using it... some/most are just opinions.
YMMV - I was going to go through the whole scope, Triggering, Digital Channels, Arb Gen, etc  but never got the options
activated.  This was just my personal notes, I was going to post something more formal - better explained/worded.

But just so I feel I'm contributing in some small way while I wait for the new keys.

Here's a PDF.

 

Offline 9a4wy

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Re: Siglent SDS2000 new V2 Firmware
« Reply #32 on: November 27, 2015, 08:36:02 am »
Did you install licenses in the FW V1??
I had a same problem with licenses and I had to load back FW v1, then install licenses and then go to FW v2  :(
 

Offline analogNewbie

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Re: Siglent SDS2000 new V2 Firmware
« Reply #33 on: November 27, 2015, 01:01:26 pm »
Does it mean that the SDS2072 can get 70M with the new V2 firmware?
 

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Re: Siglent SDS2000 new V2 Firmware
« Reply #34 on: November 27, 2015, 01:07:13 pm »
Does it mean that the SDS2072 can get 70M with the new V2 firmware?
Yep.  :-+
All models in the SDS2000 range benefit from this new V2 FW.

Check the Changelog file on the first page for the other improvements......now 140K wfps, 1mV range.....
« Last Edit: November 27, 2015, 01:25:43 pm by tautech »
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Offline analogNewbie

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Re: Siglent SDS2000 new V2 Firmware
« Reply #35 on: November 27, 2015, 01:33:08 pm »
Does it mean that the SDS2072 can get 70M with the new V2 firmware?
Yep.  :-+
All models in the SDS2000 range benefit from this new V2 FW.

Check the Changelog file on the first page for the other improvements......now 140K wfps, 1mV range.....

Does this model also have a upgrade bandwidth license input menu? >:D
 

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Re: Siglent SDS2000 new V2 Firmware
« Reply #36 on: November 27, 2015, 01:52:57 pm »
Does it mean that the SDS2072 can get 70M with the new V2 firmware?
Yep.  :-+
All models in the SDS2000 range benefit from this new V2 FW.

Check the Changelog file on the first page for the other improvements......now 140K wfps, 1mV range.....

Does this model also have a upgrade bandwidth license input menu? >:D
:)
Not with this V2 FW but Siglent has been adding BW upgrade options in the FW of their other products but for now they have not offered any upgrades or pricing.  ???
In the future we hope they will.  8)
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Offline cidcorp

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Re: Siglent SDS2000 new V2 Firmware
« Reply #37 on: November 27, 2015, 02:55:53 pm »
Did you install licenses in the FW V1??
I had a same problem with licenses and I had to load back FW v1, then install licenses and then go to FW v2  :(

No, but the Scope ID that I provided them was the one for the beta v2 firmware, and I tried to install the keys using the released v2
firmware.  So yes it was my own fault for assuming the keys were only related to the serial number (which wouldn't have changed).

Siglent and Batronix have been attentive and the codes were regenerated, all is fine now.
 

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Re: Siglent SDS2000 new V2 Firmware
« Reply #38 on: November 27, 2015, 09:27:58 pm »
Did you install licenses in the FW V1??
I had a same problem with licenses and I had to load back FW v1, then install licenses and then go to FW v2  :(

No, but the Scope ID that I provided them was the one for the beta v2 firmware, and I tried to install the keys using the released v2 firmware.  So yes it was my own fault for assuming the keys were only related to the serial number (which wouldn't have changed).

Siglent and Batronix have been attentive and the codes were regenerated, all is fine now.
I'm surprised the Beta would have affected the scope ID, but that's why they call them Beta's I suppose.  :scared:

Let's hope your option install goes properly this time.  :popcorn:

BTW, thanks for your V2 FW tweak ideas, look forward to more constructive ideas like these.  :-+
« Last Edit: November 27, 2015, 09:39:50 pm by tautech »
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Offline rf-loop

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Re: Siglent SDS2000 new V2 Firmware
« Reply #39 on: November 28, 2015, 03:10:08 am »

I'm surprised the Beta would have affected the scope ID, but that's why they call them Beta's I suppose.  :scared:


Yes, there was error in beta and it add one 0 to ID.
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Re: Siglent SDS2000 new V2 Firmware
« Reply #40 on: November 28, 2015, 07:35:20 pm »
Has the jump from 28M to 70M memory depth assisted users doing Decoding work in capturing longer communication strings?
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Offline Performa01

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Re: Siglent SDS2000 new V2 Firmware
« Reply #41 on: November 29, 2015, 08:35:13 pm »
Finally got the time to give the first release of the V2 FW a try and thought I’d share some of my findings…

I started with the new (and unexpected) features, in particular memory depth and vertical sensitivity.

First, I want to comment on some objections that have been raised already in this thread.

After FW-update, I noticed that the confirmation-beep for keystrokes was on, which I don’t want. So I walked through several menus (‘Utility’, ‘Display’ and ‘Acquisition’ in particular) to make sure that all settings were to my liking. After that, the trace was suddenly gone. Turning the corresponding vertical sensitivity knob once brought it back immediately. A very minor issue in my book.

The soft buttons generally show the currently selected option. They certainly do this when there is a menu behind the button, but also when it is just a toggle. This is consistent throughout the UI and seems very convenient to me. As far as I remember that’s not uncommon and I am pretty sure it is the same on the Rigols for instance. Generally, I would like it to stay that way.

Even though a small DC offset error is to be expected at high vertical sensitivities, I took a closer look on the SDS2000.  A self-calibration had been performed some 20 minutes after cold start and then the scope was running for several hours. After that, I checked the DC offset on my SDS2304 (without performing another self-calibration), and with GND-coupling, no significant error was visible on any of the 4 channels.

With DC-coupling, internal 50 ohms termination and open inputs, the errors at 1mV/div were as follows:
Ch.1: -740µV, Ch.2: -60µV, Ch.3: -360µV, Ch.4: -80µV.

After performing another self-cal, I got the values below:
Ch.1: -340µV, Ch.2: -360µV, Ch.3: -560µV, Ch.4: -640µV.

It appears like the self-cal cannot really tweak out the DC offset error. But with 2mV/div vertical sensitivity, only a minor DC offset error of <+300µV can be seen. Turning the sensitivity down to 1mV/div, the offset error changes sign and can get quite significant on some channels.
 

Offline Performa01

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Re: Siglent SDS2000 new V2 Firmware
« Reply #42 on: November 29, 2015, 08:35:56 pm »
70Mpts Memory Depth:

Now we actually get up to 35Mpts per channel and 70Mpts interleaved, but in terms of sample rate preservation, it is ‘only’ 28Mpts and 56Mpts, respectively.

With all channels on, we can have 1GSa/s up to 2ms/div, which translates to a record length of 28Mpts. At 5ms/div, the memory increases to 35Mpts, but still the sample rate drops to 500MSa/s, as we would actually need 56Mpts in order to preserve the 1GSa/s.

Likewise, in interleaving mode, i.e. just channel 1 or 2 plus channel 3 or 4 turned on, we get 2GSa/s up to 2ms/div, which results in a record length of 56Mpts. At 5ms/div, the memory increases to 70Mpts, but the sample rate drops to 1GSa/s

With the digital channels enabled, things get a little more complicated. Generally, the sample rate on digital channels cannot exceed 500MSa/s.

With all analog channels on, we can maintain 1GSa/s up to 1ms/div, which means 14Mpts. At the same time, digital channels have 500MSa/s and 7Mpts.
At 2ms/div, analog channels drop to 500MSa/s, thus now being equal to the digital sample rate, and memory depth is still 14Mpts on analog and increases to 14Mpts for the digital channels as well.

In interleaving mode, we can maintain 2GSa/s up to 1ms/div, which means 28Mpts. At the same time, digital channels have 500MSa/s and 7Mpts.
At 2ms/div, analog channels drop dramatically to 500MSa/s, and memory depth is s14Mpts for both analog and digital channels.
Slower timebase settings don’t affect memory depth any further, but sample rate on both analog and digital channels drops accordingly.

Conclusion:
When using the SDS2000 as a DSO, we actually benefit from the increased memory. As an MSO, nothing seems to have changed, so one might assume that a major portion of the additional 42Mpts memory comes from the digital part and consequently is only available when digital channels aren’t in use.
Anyway, I think this is a clever move and I’m quite comfortable with it.

EDIT: Corrected analog samplerate on interleaved mixed mode.
« Last Edit: December 14, 2015, 11:14:00 pm by Performa01 »
 

Offline Performa01

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Re: Siglent SDS2000 new V2 Firmware
« Reply #43 on: November 29, 2015, 08:40:09 pm »
Vertical Sensitivity down to 1mV/div:

One of the most amazing (and unexpected) gifts – for me, at least – is the increased vertical sensitivity. On the other hand, this scope has always shown exceptionally low noise, so making 1mV/div available appears to be logical step. Is this just a marketing gag or is it actually useful? Let’s see…

Since the hardware has not changed, it is rather unlikely that the increase in vertical sensitivity has been achieved by additional gain in the frontend – it is far more likely some form of software trick.

I tried hard to find a test setup that clearly reveals what’s going on and finally ended up with the following:
Scope: Single channel, 50ohms, x1, 20MHz BW limit, 500ns/div, normal acquisition, 14kpts, dot mode.
Gen.: 5MHz, 3mV rms.

All vertical sensitivities down to 2mV/div give 25 levels per division. Consequently, 200 levels are used for full scale and the difference to 256 (for an 8-bit ADC) is left over to give some headroom for overdriving the inputs. This can be verified by acquiring a waveform that doesn’t quite fit the screen vertically and we can still get an undistorted picture by reducing the vertical sensitivity after the fact – i.e. in stop mode. 
For 1mV/div, I can only see ~12 levels and, even more descriptive, I don’t see any significant difference compared to 2mV/div. zoomed to 1mV/div after stopping the acquisition.

Well, together with the rather weird DC-offset issue mentioned earlier, this indicates it is indeed just a software trick, but apart from that, is it of any use?

Same settings as above, DC coupled rising edge trigger, noise rejection off.
- at 2mV/div, I could trigger down to ~500µV rms (with tweaking the trigger level)
- at 1mV/div, I could trigger down to ~250µV rms (with tweaking the trigger level)

All in all, triggering seems to be a little worse than what it used to be with prior FW versions at 2mV/div, but with the new 1mV/div setting, it is certainly at least as good, probably even a bit better.

Last not least the most amazing surprise: the automatic band limit has gone!

That means, we can use the full bandwidth of >300MHz even at the 1mV setting!

This raises the question about the noise performance of the current implementation.

With 20MHz BW-limit on:
- <600µVpp for memory sizes from 70 down to 14Mpts.
- <520µVpp for memory sizes from 5.6Mpts down to 140kpts.
- <440µVpp for memory sizes from 56 down to 14kpts.


Full bandwidth (>300MHz):
- <1.28mVpp for memory sizes from 70 down to 14Mpts.
- <1.16mVpp for memory sizes from 5.6 down to 1.4Mpts.
- <1.08mVpp for memory sizes from 560 down to 140kpts.
- <1.08mVpp for memory sizes from 560 down to 140kpts.
- <1.08mVpp for memory sizes from 560 down to 140kpts.
- <1.00mVpp for memory sizes from 56 down to 28kpts.
- <920µVpp for memory size 14kpts.

The noise levels are still low for the bandwidth. All in all, apart from the DC-offset issue, the implementation of the 1mV/div sensitivity appears to be not too bad in my opinion.
 

Offline Performa01

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Re: Siglent SDS2000 new V2 Firmware
« Reply #44 on: November 29, 2015, 09:11:49 pm »
Waveform Update Rate:

Well, as this seems to be the darling topic of today’s DSO enthusiasts, I had to take a deeper look into that for the final V2 implementation.

I have only used 7/14kpts for this test throughout; longer memory would certainly slow down the waveform update rate on slower timebases, where the additional memory comes into effect.
Tests have been generally carried out in dot mode, as I don’t see any reason for using vector mode at all with this scope.

The results can be found in the attached image. Results for sin(x)/x are only given for timebases faster than 50ns/div, as the reconstruction filter is not used at the slower timebase settings, hence it makes no difference whether it’s turned on in the menu.



The differences between the six configurations reveal the relative complexity of the processing going on. It might be surprising at first, that Ch. 4 only and Ch. 2+ 4 are slower than the other configurations (except for digital channels on), but this is because of the 14kpts memory as opposed to just 7k in the non-interleaved mode.

As a conclusion, the banner spec. 140k Wfrm/s apply only for single channel at 5ns/div; apart from that, a maximum waveform update rate of 70k would be a more realistic figure.


EDIT: As mentioned before, memory depth was kept at 7/14 kpts during the entire test, so in order to prevent aliasing I could not do the test with a constant (high) input frequency. The 2nd column of the table below shows the input frequency used, and for timebases <10ns it has been chosen such that we always get one signal cycle per horizontal division.
All the measurements show the average over a period of 10 seconds. This is the only way to get close to the true sustained update rate, as the update occurs in bursts with major gaps between them.

EDIT2: corrected 14pts -> 14kpts
« Last Edit: January 23, 2016, 02:18:40 am by Performa01 »
 

Online tautechTopic starter

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Re: Siglent SDS2000 new V2 Firmware
« Reply #45 on: November 30, 2015, 05:36:12 am »
@Performa01
The apparent visible noise floor can be made much less with selection of Slow update in the Acquire menu as shown in reply #27. Doing this helped easily display the offset in the attached screenshot.
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Offline rf-loop

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Re: Siglent SDS2000 new V2 Firmware
« Reply #46 on: November 30, 2015, 06:11:19 am »
Here wfm/s rates tested with previous Rev 2.0 Beta test version
(Later I'm back in working I will also do more tests with official FW 2)
All wfm/s update rates are averages so that they include least several TFT update turns.

« Last Edit: November 30, 2015, 06:17:26 am by rf-loop »
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Offline Performa01

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Re: Siglent SDS2000 new V2 Firmware
« Reply #47 on: November 30, 2015, 10:02:11 am »
@Performa01
The apparent visible noise floor can be made much less with selection of Slow update in the Acquire menu as shown in reply #27. Doing this helped easily display the offset in the attached screenshot.

Good tip!
On the other hand, turning the 20MHz bandwidth limit on, plus limiting the memory depth to 14kpts significantly reduces the noise too - and this is what I did.
Maybe adding the slow update as a third measure might reduce the noise even further - will try this the next time I have to investigate offset levels...
 

Offline rf-loop

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Re: Siglent SDS2000 new V2 Firmware
« Reply #48 on: November 30, 2015, 01:48:14 pm »
@Performa01
The apparent visible noise floor can be made much less with selection of Slow update in the Acquire menu as shown in reply #27. Doing this helped easily display the offset in the attached screenshot.

Good tip!
On the other hand, turning the 20MHz bandwidth limit on, plus limiting the memory depth to 14kpts significantly reduces the noise too - and this is what I did.
Maybe adding the slow update as a third measure might reduce the noise even further - will try this the next time I have to investigate offset levels...

Limiting memory depth do not reduce noise. All noise is still there. But, it looks better due to less data. It can easy test. Turn persistence on with small meory/low sample rate and wait... all noise is there. More data, more peaaks come visible.
This is still valued paper for evaluating vertical noise charaacters. http://cp.literature.agilent.com/litweb/pdf/5989-3020EN.pdf

With slow update mode, we just only reduce collected data. It need also note that more wfm/s speed...more we collect data in some amount of time. Also this is well explained in Agilent paper where they talk about example where is very slow LeCroy and then fast agilent what collect thousends of times more data in same time and then trace looks more fat.

filtering  _random_ noise out, example for better visualization slow (nearly like DC) offset drift. My opinion is that averaging is one best method if want see offset (DC) level under noise. Also ERES can try.

When look offset drift with 2 - 5mV/div it need also note auto-cal function and if it is enabled, it some times do automatically offset corrections.

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Offline Performa01

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Re: Siglent SDS2000 new V2 Firmware
« Reply #49 on: November 30, 2015, 05:58:19 pm »
Limiting memory depth do not reduce noise. All noise is still there. ...
With slow update mode, we just only reduce collected data. ...

Nobody has claimed anything else. I thought it was clear that we were just talking about visible (perceived) noise on the screen.


filtering  _random_ noise out, example for better visualization slow (nearly like DC) offset drift. My opinion is that averaging is one best method if want see offset (DC) level under noise. Also ERES can try.

Yes, that's the obvious way to do it. Shame I didn't think of it right from the start - reason probably is, that visible noise with 20MHz bandwidth limit and small memory was already low enough to determine the DC-offset with reasonable accuracy.


When look offset drift with 2 - 5mV/div it need also note auto-cal function and if it is enabled, it some times do automatically offset corrections.

Ok, I've never tried auto-cal. yet. Should definitely give it a try next weekend, even though I am a bit skeptical that auto-cal. can do some additional magic when self-cal. has failed already.
As I've mentioned before, the offset error is tiny and absolutely insignificant at 2mV/div, whereas it gets quite large on some channels at 1mV/div and changes sign on top of that. Almost looks like the firmware just multiplies the RAW ADC values by 2 without taking the offset correction value into account (that is clearly in effect at 2mV/div, as there is barely any offset error visible).
 


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