Author Topic: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes  (Read 269034 times)

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Offline SMB784

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1675 on: August 10, 2020, 03:02:14 am »
I've been having the 1104 for several weeks now - still learning.
One thing that caught my eyes and I find pretty annoying is that I cannot see the top line of the screen unless I am looking perpendicular at the screen itself. If I'm standing in front of my bench - hence the scope is at "belly height" I cannot see it. The plastic frame around the screen should have been chamfered more to avoid this issue which I find pretty major as the top line has some crucial information!

I did a quick search on this thread and I do not see anybody else noticing it but it is so obvious to me.

I too have noticed the and it does annoy me. Viewing angles are important!

Offline Ringmodulator

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1676 on: August 14, 2020, 05:09:22 pm »
Has already someone botherd to exchange the Intensity/Adjust encoder with a detented encoder?

I did this with my two other DSOs (different brand) and found it to be a great enhancement for me.

More often than not, I manage to cause an unwanted jump in value or selection when pressing the knob.

Maybe, tis is just me...

Regards
Chris
 
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Offline tautech

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1677 on: August 14, 2020, 07:41:25 pm »
Has already someone botherd to exchange the Intensity/Adjust encoder with a detented encoder?

I did this with my two other DSOs (different brand) and found it to be a great enhancement for me.

More often than not, I manage to cause an unwanted jump in value or selection when pressing the knob.

Maybe, tis is just me...

Regards
Chris
Chris, you can bypass using the encoder for large adjustments by when the LED is lit for it signifying it needs input, press it again and the virtual keyboard appears where you can select digits and units.
I find using it between thumb and forefinger with other fingers resting on the top of the scope works best and better helps prevention of moving the encoder while a selection is made.
A larger knob works well to and you can exchange one of the larger knobs to it which makes it less sensitive to movements.
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Offline patman27

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1678 on: August 17, 2020, 01:44:44 am »
Has already someone botherd to exchange the Intensity/Adjust encoder with a detented encoder?

I've been wondering the same thing.  :popcorn:
 

Offline gamerpaddy

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1679 on: August 17, 2020, 09:27:53 am »
Hey,
i got a problem with my sds1104x-e, it wont recognize any usb drives anymore.
(i did that sds1204x-e firmware thing back in the day, usb worked after that no problems. it worked just 2 months ago when i last used it, havent done anything but maybe measuring one or two things since.)

when i insert a usb drive, it says "USB flash drive removed" hitting the screenshot button says, no usb flash drive detected.

i tried with 5 different drives ranging from 2 to 64gb, all FS from exFAT over FAT32 to NTFS. USB drives, usb card readers with sd cards in it. drives that definately worked before.
i hit (in windows) "format to device defaults" to reset block sizes, i tried with volume name and without..
i tried the back and front usb port, i hit default to reset settings, i disconnected power for a while, i tried rebooting..
i tried via the save/recall menu, via the system menu (firmware, configuration) also nothing.
 i cant get it to work for some reason.

anyone got an idea?


EDIT:
i have found 4gb sd card that works! no idea why my 2gb stick with fat32 didnt, nor the sticks that worked before.
updated firmware to 6.1.35R2 but still usb drive cannot be detected. i also tried formatting it on another computer and from within a virtual box running kali.
« Last Edit: August 17, 2020, 10:07:27 am by gamerpaddy »
 

Offline Ringmodulator

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1680 on: August 17, 2020, 10:25:54 am »
Hi,

I just use the webinterface for screenshots, so no juggling with USB sticks.

The 10€ WLAN adapter spares me from having to plug in the LAN cable in my non-permanent setup.

OK, not eaxtly a solution to your question, just a workarround...

Chris
 

Offline HendriXML

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Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes - C4:COUPLING?
« Reply #1681 on: August 20, 2020, 11:51:39 am »
Hi!,

When I execute the SCPI query C4:COUPLING? it fails, while C3:COUPLING? returns a valid answer: D1M. I'm quite sure it is a bug.

Also I cannot use the remote interface in Windows Edge browser, the mouse cursor dissapears when it enters the UI. Internet explorer however works fine.

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Offline HendriXML

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes - C4:COUPLING?
« Reply #1682 on: August 21, 2020, 10:58:28 am »
Hi!,

When I execute the SCPI query C4:COUPLING? it fails, while C3:COUPLING? returns a valid answer: D1M. I'm quite sure it is a bug.
This query returns wether the channel is AC, DC or GND, which is quite important. However EasyScope (uses SCPI) does not show this value. This makes me wonder wether it is a known bug.
I can't think of any reason why channels 1-3 work, but the 4th wouldn't.
Maybe someone is willing to verify this issue?
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Offline HendriXML

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes - C4:COUPLING?
« Reply #1683 on: August 21, 2020, 07:11:40 pm »
Hi!,

When I execute the SCPI query C4:COUPLING? it fails, while C3:COUPLING? returns a valid answer: D1M. I'm quite sure it is a bug.
This query returns wether the channel is AC, DC or GND, which is quite important. However EasyScope (uses SCPI) does not show this value. This makes me wonder wether it is a known bug.
I can't think of any reason why channels 1-3 work, but the 4th wouldn't.
Maybe someone is willing to verify this issue?
Found a workaround! Using the short version C4:CPL? seems to be having no problem.
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Offline HendriXML

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1684 on: August 21, 2020, 09:34:08 pm »
Found some buggy SCPI behavior:
If one has a fine adjustment of the V/Div, then setting the trigger level to a certain value goes wrong.
For example if the sensitivity is 5.10V/Div, and the trigger level is set to 10V. The actual trigger level becomes 5.1V.
I guess when the trigger "ADC value" is calculated, the coarse round up is used (10V/Div). Then this wrong ADC value, is then converted and shown as the triggerlevel. Thus: TriggerLevel SCPI -> TriggerLevel ADC -> TriggerLevel UI
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Offline HendriXML

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1685 on: August 24, 2020, 01:26:38 pm »
I'm in the process of develloping a script that not only extract a screenshot and trace data. But also reports the settings on the scope used in such a way that they can easily be redone (inifile data, see below).
Code: [Select]
[VISA]
ScopeRN=TCPIP0::scope::inst0::INSTR

[Scope]
AcquireWay=PeakDetect
MemorySize=70K
TDiv=50 ms·div⁻¹

[Scope.Trigger.Select]
TriggerSelect=WIN

[Scope.Trigger]
TriggerPattern=C1,X,C2,X,C3,X,C4,X,STATE,AND
TriggerDelay=0 s

[Scope.CH1]
Enabled=1
Unit=A
Attenuation=1
VDiv=100 mA·div⁻¹
VOffset=100 mA
Coupling=DC
BandwidthLimit=1

[Scope.CH2]
Enabled=1
Unit=V
Attenuation=1
VDiv=4.94 V·div⁻¹
VOffset=0 V
Coupling=DC
BandwidthLimit=1

[Scope.CH3]
Enabled=1
Unit=V
Attenuation=1
VDiv=1.3 V·div⁻¹
VOffset=0 V
Coupling=DC
BandwidthLimit=1

[Scope.CH4]
Enabled=1
Unit=V
Attenuation=1
VDiv=1 V·div⁻¹
VOffset=-3 V
Coupling=DC
BandwidthLimit=1
However in the case of the TRSE? query. Not all parameters are returned (depending on the trigger type). Most importantly the trigger source, which is needed to extract trigger levels and more.
I cannot understand why, because it is easier to encode the status in a responds, then it is to decode it.
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Offline heatbreak

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1686 on: August 26, 2020, 10:44:30 pm »
Why is the X-Cursor time measurement only works when both X1 and X2 cursors are visible on the screen?  Like I zoom in on a pulse making it span multiple screens, set X1 to the beginning of the pulse and X2 to the end and the time measurement is only accurate when both X1 and X2 are on screen.  If one or both is not visible on screen, then the measurement is off.  I don't remember seeing this behavior in Agilent scopes.  In the following two pictures, I haven't change the time scale nor move the cursors.  The only thing I did was move the pulse to the right.  I have FW 6.1.35R2.
 

Offline HendriXML

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes - C4:COUPLING?
« Reply #1687 on: August 27, 2020, 11:34:17 am »
When I execute the SCPI query C4:COUPLING? it fails, while C3:COUPLING? returns a valid answer: D1M. I'm quite sure it is a bug.
This issue is BTW resolved in the newest firmware update: C5:COUPLING? typo in name.
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Offline SMB784

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1688 on: August 27, 2020, 02:35:53 pm »
I noticed that fixing the restrictions on the WIFI network name has not been implemented in FW version 6.1.35R2.  Is this planned for a future release?

Offline tautech

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1689 on: August 27, 2020, 10:36:42 pm »
Why is the X-Cursor time measurement only works when both X1 and X2 cursors are visible on the screen?  Like I zoom in on a pulse making it span multiple screens, set X1 to the beginning of the pulse and X2 to the end and the time measurement is only accurate when both X1 and X2 are on screen.  If one or both is not visible on screen, then the measurement is off.
Yes this might be an issue in single timebase mode but it certainly isn't in Zoom mode.
A couple of screenshots attached for your study.

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Offline nez

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1690 on: September 15, 2020, 04:27:03 am »
EDIT:  Inline pictures didn't seem to work.. guess they are at the bottom of the post...



I think I found some problems/strangeness with phase and amplitudes when comparing two signals, depending on which channels are being used.

I just got an SDG2042X AWG (now unlocked for 120 MHz sine), and was messing around measuring the phase difference of two dissimilar BNC cables on my SDS1104X-E scope (unlocked to 200 MHz).

Can someone advise me on whether I'm seeing a problem with just my scope, or is it with the model/firmware in general?


Basically, I am seeing incorrect phase and amplitudes measurements when comparing two signals, depending on which channels are enabled and at what timebase is set.  There are big differences depending on if I'm using two channels from the same ADC, or one channel from each ADC.  For example, using chans 1 and 3, the phase difference is wrong by about 40 degrees (at 120 MHz sine) from what it should be -- at least, what I assume it should be.

The issues occur when directly viewing the waveforms and are also reflected in Bode plots done on the scope.


Test setup:
AWG - Both channels set to 120 MHz sine wave, tracking on, HiZ.
Using two different BNC cables with a slightly different lengths, without 50 Ohm terminators (just waiting for ebay order to arrive).
(One cable came with the AWG, the other is a PICO MI030)


Here are two BodePlot II plots demonstrating the difference while just changing which scope input channels are connected and enabled.

[attach=1]
[attach=2]



Case 1:
Using channels 1 and 3, vertical scale @ 500 mV/div, averaging on

  1 ns/div:  33.88 degrees,  780.00 ps skew
  2 ns/div:  34.56 degrees,  780.00 ps skew
  5 ns/div:  38.14 degrees,  883.33 ps skew,  3.32 Vpp
 10 ns/div:  38.07 degrees,  880.95 ps skew,  3.32 Vpp
 20 ns/div:  38.39 degrees,  846.15 ps skew,  3.32 Vpp
 50 ns/div:  72.09 degrees,    1.68 ns skew,  3.32 Vpp
100 ns/div:  72.11 degrees,    1.68 ns skew,  3.32 Vpp
200 ns/div:  72.22 degrees,    1.68 ns skew,  3.32 Vpp
500 ns/div:  72.22 degrees,    1.67 ns skew,  3.32 Vpp
  1 us/div:  72.22 degrees,    1.68 ns skew,  3.32 Vpp
     <etc>           <etc>            <etc>   3.32 Vpp
200 us/div:          <n/a>,           <n/a>,  3.66 Vpp * Sample rate drops to 500 MSa/s at this timebase


To get a more steady phase result I turned on averaging over 1024 samples in the Acquire menu, but the same changes across timebases are observed without averaging.

[attach=3]
[attach=4]



Case 2:
Using channels 1 and 2, vertical scale @ 500 mV/div, averaging on

  1 ns/div:  32.81 degrees,  720.00 ps skew,  3.66 Vpp
  2 ns/div:  32.43 degrees,  740.00 ps skew,  3.66 Vpp
  5 ns/div:  32.38 degrees,  750.00 ps skew,  3.66 Vpp
 10 ns/div:  31.97 degrees,  756.04 ps skew,  3.66 Vpp
 20 ns/div:  33.09 degrees,  742.86 ps skew,  3.66 Vpp
 50 ns/div:  32.38 degrees,  761.54 ps skew,  3.66 Vpp
100 ns/div:  32.67 degrees,  774.44 ps skew,  3.66 Vpp
200 ns/div:  32.87 degrees,  781.45 ps skew,  3.66 Vpp
500 ns/div:  32.98 degrees,  781.45 ps skew,  3.66 Vpp
  1 us/div:  32.29 degrees,  781.45 ps skew,  3.66 Vpp
 50 us/div:  33.18 degrees,  878.07 ps skew,  3.66 Vpp
100 us/div:  32.60 degrees,      <unstable>,  3.66 Vpp
200 us/div:          <n/a>,            <n/a>, 3.66 Vpp


NOTE 1:
Without averaging, the skew measurements start flipping around all over the place at 100 ns/div and longer timebases. At 50 ns/div and shorter, the skew values remain in the expected range of values (given the jitter specs of AWG, I think).

Even with averaging on, the skew values start having trouble at 100 us/div. It ranges around between 0.4 and 5+ ns, both positive and negative values.  Not sure why it has trouble however, because it is still at 500 MSa/s at this point.  Stopping the scope and zooming in, the signals and relative spacing look ok.

The case 2 phase measurements are ok all the way through 100 us/div, with or without averaging.  Further increases in time base drops the sample rate to 250 MSa/s, 100 MSa/s, etc. so I think aliasing prevents correct measurements of this frequency anyway.

NOTE 2:
For Case 1, when averaging is off the skew measurements do NOT vary wildly like in Case 2, all the way up to 100 us/div.  The values are still wrong in Case 1, but they are stable.

[attach=5]
[attach=6]



Case 3:
This case shows two separate problems.

1. Each time I disable and re-enable that third channel, the phase difference between the two waveforms changes randomly! Both displayed and auto-measured.  Assuming ~32 degrees is expected, I can get it to vary between 24-54 degrees without doing anything else, demonstrated in the pics below.

2. The amplitude of both waveforms changes when I enable a third (unused) channel, from ~3.33 to ~3.66 V (10%).  I think 3.66 V is the correct one, but I technically don't know for sure since I lack any other test equipment to valildate against.

[attach=7]
[attach=8]
[attach=9]
[attach=10]



I collected more info, but got bogged down with so many permutations of quirks I found, so I thought I'd make this initial post first and see where it leads.







« Last Edit: September 15, 2020, 04:31:57 am by nez »
 

Offline HendriXML

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1691 on: September 15, 2020, 08:35:01 am »
Maybe this is a result of sine intrpolation. On 1 Gs/s you would get like 8 samples / cycle, on 500 Ms/s you only get 4. I think that may explain the difference in enabling a channel. You could switch to dot mode and see wether something strange is also happening. My guess is that different lengths of cables result in different interpolation artifacts/sine fitting.
« Last Edit: September 15, 2020, 08:43:21 am by HendriXML »
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Offline nez

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1692 on: September 15, 2020, 09:37:17 pm »
I got some 50 Ohm terminators today, so I took some new screen caps that still demonstrate the issue, including dots mode and bode plots.

It's a very simple setup.

Test setup:
50 Ohm terminators at scope inputs.
The two cables have slightly different lengths, so some phase offset is expected.
Bode plots are 4 Vpp, 50 Ohm, swept from 10 Hz to 120 Mhz.

The other screen caps (waveforms) are with 120 MHz, 4 Vpp sine wave from AWG on both output channels (channel tracking on).

Result:
Bode plots have very different phase results across the entire sweep, depending on which pair of channels are used.
There is also a difference in amplitudes.

I noticed that the timebases used during the Bode plot capture are at 100 ns/div and up (slower).  This matches what I'm seeing while inspecting the waveforms at different timebases (the most error exists at 50 ns/div and up when using chan 1+3, for example).

Note the phase measurement in the screen cap of chans 1 + 3 @ 50ns/div.  The equivelent measurement with chans 1 + 2 don't have this phase error, even though the sample rate is halved.


 

Offline HendriXML

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1693 on: September 16, 2020, 09:23:19 am »
Nice screenshots. I think the differences on the simple sine graphs are now consistent (looking at the persistent dot display)?
That time difference would correspond to a cable length difference about 25 cm. I guess you could safely use skew to make them align. (I'm not a bode plot user, so won't comment on that)
« Last Edit: September 16, 2020, 09:27:31 am by HendriXML »
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Offline nez

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1694 on: September 17, 2020, 01:11:52 am »
Nice screenshots. I think the differences on the simple sine graphs are now consistent (looking at the persistent dot display)?
That time difference would correspond to a cable length difference about 25 cm. I guess you could safely use skew to make them align. (I'm not a bode plot user, so won't comment on that)

Well, that isn't exactly the issue.  The separate Bode plots should all show virtually the same curve values for all permuations of channels used -- each plot is using the same BNC cables and AWG signals, after all.

Yeah the lines are straighter when using the 50 Ohm termination compared to my first, unterminated trials, but I didn't mean that the curviness within an individual plot before was a problem (since it was expected anyway due to reflections). The problem is that multiple plots don't match each other, and I'm seeing various disparities when viewing the waveforms.

It seems like there are some problems with how the two scope ADCs interplay with each other.

Also, I just measured my cables, and they are only about 4 or 5 cm different in length.
Cable 1: ~104 cm
Cable 2: ~108.5 cm


I decided to stop being lazy about my screen caps, and mark them up with notes to illustrate the aspects I'm looking at, attached below.

The Bode plots here are using Vpp for amplitude instead of dB this time.

I've added a bonus Bode plot showing an even stronger error I saw once...

EDIT:  All plots are with 4 Vpp signals from AWG.


« Last Edit: September 17, 2020, 01:23:03 am by nez »
 

Offline HendriXML

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1695 on: September 17, 2020, 08:39:05 am »
I don't know how the fase difference is calculated, will the Siglent use the sampled data or the data that is made ready to display. One explanation of your problem would be the latter. There's about one pixel difference. Going on an even slower timebase, how does the fase difference calculation react?
Doing such calculations with a 1 Gs/s scope, with a 120 Mhz signal might be a bit too much to ask. I have no comparison, so I don't know what to expect...
« Last Edit: September 17, 2020, 10:19:34 am by HendriXML »
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Offline nez

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1696 on: September 17, 2020, 09:21:39 am »
I've got some data from different timebases in the tables in my original post.  In "Case 1" for chans 1+3, I've color coded where the measurements vary.

I'm hoping someone can test a similar setup!  I'll probably buy a 'matched' set of BNC cables soon for a better baseline without length differences.
 

Offline exe

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1697 on: September 17, 2020, 09:26:53 am »
Did you try swapping cables?
 

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1698 on: September 17, 2020, 10:26:10 am »
After thinking about this some more, my guess would be that the fase difference calculation is done after interpolation. Thus "display data". That data will have poor horizontal "resolution/cycle" (vertical reso is alway poor  :D) when displaying a large number of cycles. This would lead to the conclusion to do such a calculation with a minimal amount of cycles.
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Offline nez

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1699 on: September 17, 2020, 10:47:25 am »
Did you try swapping cables?

I just tried it out.  I swapped the cables, then kept that order while running the same Bode plot configurations as previously (see attached).  Problem remains, but of course the phase lines change to reflect the reversed order of cables.

After thinking about this some more, my guess would be that the fase difference calculation is done after interpolation. Thus "display data". That data will have poor horizontal "resolution/cycle" (vertical reso is alway poor  :D) when displaying a large number of cycles. This would lead to the conclusion to do such a calculation with a minimal amount of cycles.

Hmm not sure exactly, but whatever the cause, doesn't this make BodePlot II broken and instill uncertainty in general measurements? (...unless it's just a problem with my specific unit).  I can't really know what values to trust.

Edit:  Also, don't forget, the error is across the entire frequency sweep in the Bode plots.. so even much lower frequencies, the same time offset error is present (a 'fixed' amount of time then factored as a percentage of the 360 degree cycle, it seems to me).

« Last Edit: September 17, 2020, 10:59:16 am by nez »
 


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