Siglent SDS800X HD 12 bit DSO's

[eTobey]

There is not the slightest bit of intelligence in that way of displaying. On the contrary, it causes a lot of confusion.

There are many more (confusing) situations like this. Like showing measurements with an accuracy of nanoseconds, when the accuracy is much less (in the order of magnitudes); Displaying wrong decoded bytes when having the wrong scale; not showing search events, when running through them... the list goes on...
If you believe the scope in those cases, then you are wasting time, looking for problems in your circuit, that are actually not there.

That stupidity should be stopped. 

I also would like to add the stupidity, of using pale colors for the channels (in general) here.    (No thats not this Siglent, and thats one of the reasons i like it, because its less stupid in this regard).

[Kleinstein]

The measurement results are often shown with more digits than the accuracy - that is normal and OK. Showing only the accurate digits would be too little and a real fail. It is only the digits well below noise levels that make no sense. How much noise is actually there can take quite some extra effort. It is thus common and no problem to show a few extra digits.
It already looks like the SDS800 is limit the digit in some cases quite reasonable  - looks more on the good side.

[mawyatt]

Agree with rf-loop, the DSO FFT display can be a source of user interpretation errors. The DSO has the proper information to limit the FFT display within Nyquist sampling limits and reduce the possible user misinterpretations and should attempt do so.

WRT the numeric display of "digits", here the user can easily judge for themselves which digits are stable and not, then choose which are important, even in some cases doing a little "mental averaging" to resolve a "noisy" digit (or even better, let the instrument do it for you!!). This is not the case with the FFT, where one must apply extra effort to determine if the displayed results actually represent the input signal or artifacts of the Signal Processing on said signal. This is not a good scenario for the casual DSO FFT user IMO.

Best

[Kleinstein]

The last FFT screens are still below the nyquest limit. Unless there is a really bad glitch the scope should know the scaling for the FFT data and there should just be not data beyond the Nyquist limit. They are however extending to beyound the input amplifier BW.

The extra peaks at 250 MHz / 500 MHz and 750 MHz could be an artifact from the ADC internals of coupling of some clock.
With the rather fast ADCs there is not only the option to use 1 fast ADC and if needed alternate to 2 or 4 channels.There is also the option to start with 2 or 4 chip internal ADCs that are used interleaved and the data than combined. If there is mismatch between the ADCs this would lead to extra spurious signals at the observed and similar frequencies. Having the artifacts outside the normal band of interest makes them less of an issue. They could still confuse the user. There could be sense in limiting the FFT display range to the actual scope BW and not very much beyond. This way only the weak 250 MHz peak would still be just in the range. I would consider such an range limit a nice to have, but not a must have.

[mawyatt]

Believe all the higher speed/resolution DSO ADCs in use are "interleaved", even the single ADC chip. The ADC is implemented with an array of slower "core" ADCs that are interleaved in time to achieve the higher sample rate. This applies to a single or multiple ADC within a single chip, or multiple chips.

Interleaving artifacts are common, but can be identified by doing a shorted input FFT on different input ranges and knowing the ADC sampling rates and clocks.

We are surprised that the NUSADC has not appeared in DSOs yet, this unique ADC has the Nyquist Limit created by the very signal its digitizing, which is Digitized Time and Amplitude.

Best 

[newbrain]

Believe all the higher speed/resolution DSO ADCs in use are "interleaved"

Almost, but not quite completely, OT:
For really state of the art ADC interleaving, look at The Signal Path video about Keysight UXR 110 GHz scope!
https://youtu.be/DXYje2B04xE?si=4fDcsXCp32WAZrzn

[mawyatt]

Believe all the higher speed/resolution DSO ADCs in use are "interleaved"

Almost, but not quite completely, OT:
For really state of the art ADC interleaving, look at The Signal Path video about Keysight UXR 110 GHz scope!
https://youtu.be/DXYje2B04xE?si=4fDcsXCp32WAZrzn

Yes, the ADCs in the Keysight are highly interleaved, even within each chip. Here's an wafer shot we did of an early development CMOS ADC chip that was used, called StingRay, which used 8 Interleaved 8GSPS ADCs, thus achieving 64GSPS thru-put.

We have more detail if interested.

Best,

[gamalot]

For some reasons, I just opened my SDS804X and took a picture of the frontend.

You can also donwload the higher resolution picture here:  https://github.com/gamalot/SDS804X-Pictures
 

[newbrain]

It would seem Siglent has the nice habit of releasing updated FW when I'm 2000 km away from my bench!
(I should travel more often then!)

Version 1.1.6.2 has been released, this is from the revsion history pdf:

1. Support decode after roll stop
2. Support decode hysteresis
3. Support Blackman-Harris and Gaussian window of FFT
4. Support XY split screen display
5. Support movable channel label
6. Support saving measurement statistics results
7. Remote reading acceleration(SERVICE->WAV ACC)
8. Optimize UI
a) Add confirmation dialog for save To Default Key
b) Remove excess zeros in the axis labels
c) When the horizontal axis labels are too long, they will be
displayed alternately up and down
d) Use real "µ" instead of small letter "u".
9. Fixed several bugs
a) When Beep enabled, physical buttons beep only until first
move of any encoder
b) When the probe is not 1X and the vertical reference is
Offset, the zoom area is unreasonable when changing the
vertical scale
c) After NTP synchronization time, the history list time is
wrong
d) When the points is ≥10M, FFT has unreasonable spurious
signals

PS: did not find any other post reporting this, if I missed it, apologies for duplicated info.

[nanopico]

Maybe it would have been more appropriate to post the announcement here:

https://www.eevblog.com/forum/testgear/sds800x-hd-bug-reports-firmware

However, it seems that some of the bugs reported by @eTobey have been fixed in this version.

[Martin72]

4. Support XY split screen display

Nice !

d) When the points is ≥10M, FFT has unreasonable spurious
signals

Even nicer....

[AndyC_772]

Anyone know if an equivalent update is due for SDS3000X HD any time soon?

[eTobey]

Had a bit of a play with it.

Movable label is very nice, it stays on the border, when the trace is moved off screen, and even comes back to the place where it was originally set.

Finally those useless zeros are gone, and even more, the grid is now aligned. The changelog states "When the horizontal axis labels are too long, they will be
displayed alternately up and down", but i cant think of a situation, where this could happen without zeros. Maybe that bug has been hit with two seperate fixes?

The XY Split view is a bit of a facepalm. Looks like 50% of the screen is not used. I really expected it to show it side by side, utilizing the whole screen. But with having less zeros, its not that bad.

The "continues run", through search events still skips events.

Still no sapce, "_" or "-"  on the first page of the keyboard.

No quick load of a created mask in the mask test has been added yet. Some issues with the mask test seem to be fixed though.

BTW:
Be aware, that some of you folks could not revert to a previous firmware version!!! (See changelog)

On the first glance it looks, like there was some effort put into it. 


EDIT:
Lists do now move in realtime, when the bar of the scrollbar is moved. It does however not work perfectly with the touchscreen: When first touching the scrollbar it does not move it, only if a minimum distance is beeing moved. But then it jumps over a few items.
It does not move the list itself, but rather the item selection (and then the list only if it exceeds the current visible items).
The scrollwheel still only works, if the mousepointer is hovering over the scrollbar.
Lists still have no alternativ background, that would make them easy to read.

Edit 2:
Gate cursor "set to border" bug still present.

Edit 3:
Encoded data (CAN) on high timescale still shows wrong values (500kbits at about 200ms/div).

[2N3055]

None of the things you mention are bugs.

Those are things you wish would be done differently on the scope.

It was explained ad nauseam to you by now.

[markus_jlrb]

Could someone be so kind and give me a hint how to list the FFT spectrum markers on top of every vertical line as a tab list on the DSO screen. (dBm values)

I was not able to find a proper menu for enabling this.

Or is this not yet included in the latest FW version?

May thanks in advance for your effort/answer.

Markus

[2N3055]

Could someone be so kind and give me a hint how to list the FFT spectrum markers on top of every vertical line as a tab list on the DSO screen. (dBm values)

I was not able to find a proper menu for enabling this.

Or is this not yet included in the latest FW version?

May thanks in advance for your effort/answer.

Markus

FFT -> Tools

In both Peaks and Markers mode, you set detection threshold, min excursion detected and enable show table.

[markus_jlrb]

Thanks for this hint 2N3055, I will try to reproduce the mentioned steps.

Markus

[markus_jlrb]

Thanks for pointing me the proper way to show the harmonic list.

Markus

[2N3055]

Thanks for pointing me the proper way to show the harmonic list.

Markus

 

[markus_jlrb]

One point to mention the reason I was not able to find the proper menu point to
activate the FFT harmonic list was the fact that some parameters and selection
points are below the bottom line of the selected window and you have to use the
vertical scrollbar to let appear the section to be used for the special purpose.

Hopefully this comment help others running in the same issue I was trapped in
not noticed that some sections of the GUI could be only made visible if the windows
slider is used.

@2N3055 thanks for your help

Markus

[tautech]

One point to mention the reason I was not able to find the proper menu point to
activate the FFT harmonic list was the fact that some parameters and selection
points are below the bottom line of the selected window and you have to use the
vertical scrollbar to let appear the section to be used for the special purpose.

Hopefully this comment help others running in the same issue I was trapped in
not noticed that some sections of the GUI could be only made visible if the windows
slider is used.

The blue slider as you call it also indicates there is more menu below the bottom of the display which can be accessed with a mouse pointer or with touch to drag the menu up to see it all.

Each will have their preference on how to do this.....

[miro123]

Hello,
I'm considering buying an oscilloscope based on the following parameters: price, analog front-end (AFE) noise level, and SFDR (spurious-free dynamic range). My current shortlist includes:
    Siglent SDS 2104X HD
    Siglent SDS 1104X HD
    Siglent SDS 814 HD
    Rigol HDO1104/1074

I have a couple of questions:

    1. Has anyone compared the noise levels and SFDR of the current generation of 12-bit Chinese scopes (Siglent/Rigol/Micsig)?

    2. Are there any hardware differences in the analog front end between the SDS2000X HD SDS1000X HD and  SDS 800? Has anyone done a teardown of these models?

I have read the datasheets but it was difficult to me to make cross-cromparision.  I cannto find the test condition of noise tests - e.g. Sample rate time base acquisition windows, oversampling ratio/hi-res. 50ohm or short  etc.etc.  I have no idea what those datasheet numbers means without explaining the test conditions.
Magnova scopes describes clear the test conditions and their numbers means something to me.

Thanks in advance for your insights
Miro

[BillyO]

Hello,
I'm considering buying an oscilloscope based on the following parameters: price, analog front-end (AFE) noise level, and SFDR (spurious-free dynamic range). My current shortlist includes:
    Siglent SDS 2104X HD
    Siglent SDS 1104X HD
    Siglent SDS 814 HD
    Rigol HDO1104/1074

If you decide on the 800 series I'd go with the SDS804X HD.  In 5 minutes you can make it a SDS824X HD and save about $300.

Also, is there an SDS2104X HD?  I see only an SDS2204X HD on the 2000 series low end?  And its nearly $2000 more than the 800 series.  Not in the same ball park at all.

As to noise floor, that should be listed in the data sheets.

The SDS2000X HD series is rated up to 500MHz, the other Siglents you mention only go to 200MHz, so I would imagine the AFE on them is a cut above the lower end models.

[2N3055]

Hello,
I'm considering buying an oscilloscope based on the following parameters: price, analog front-end (AFE) noise level, and SFDR (spurious-free dynamic range). My current shortlist includes:
    Siglent SDS 2104X HD
    Siglent SDS 1104X HD
    Siglent SDS 814 HD
    Rigol HDO1104/1074

I have a couple of questions:

    1. Has anyone compared the noise levels and SFDR of the current generation of 12-bit Chinese scopes (Siglent/Rigol/Micsig)?

    2. Are there any hardware differences in the analog front end between the SDS2000X HD SDS1000X HD and  SDS 800? Has anyone done a teardown of these models?

I have read the datasheets but it was difficult to me to make cross-cromparision.  I cannto find the test condition of noise tests - e.g. Sample rate time base acquisition windows, oversampling ratio/hi-res. 50ohm or short  etc.etc.  I have no idea what those datasheet numbers means without explaining the test conditions.
Magnova scopes describes clear the test conditions and their numbers means something to me.

Thanks in advance for your insights
Miro

Quickly:

1. Yes.There are several topics on this specifically.
2. No they are not the same. 2000xHD is 500 MHz design, and 1000 is similar to 800 250MHz design, but has 50 Ω impedance options. At high sensitivities (like 500µ/div) 2000 will have slightly less noise at the same BW.

But what are you going to do with the scope? What kind of measurements?

[mawyatt]

Not sure it belongs here, so moderators can move if desired.

While commenting on another thread.

https://www.eevblog.com/forum/projects/bode-plot-(-1hz-to-10-mhz)/

We've noted some "Suggestions" wrt to the Bode Function (some may have already been requested) on the 800 and other Siglent DSOs.

1) Have the ability to do some form of "Calibration/Normalizing", Thru for example which should produce 0dB reference.

2) Allow the user to select/modify the Frequency Selective Measurement Filter Parameters/Sample Number to trade measurement Speed vs Performance.

3) Allow below 10Hz with user notification of expected measurement time, and utilized 2) to improve such.

4) Allow user to select DC Channel Coupling for low frequency work from 3)

5) Allow upper end frequency to extend to available companion AWG frequency range (500MHz for SDG6000X series).

Anyway, just some thoughts on improving an already quite good Bode Function

Best