Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes

[GregDunn]

Right, I went both ways to the scope limits - that's what I meant by "extremes".  No change unfortunately; the shape of the waveform is pretty much the same no matter what timebase I choose, unless I increase the vertical sensitivity.

[tautech]

Greg, I've tried to replicate your measured values some to keep things in context and the way to clean the traces up is to use Eres and the full 3 bits of enhancement available.

I've got no signal on ch3 as it's only ON to reduce the sampling rate to what you have.

[GregDunn]

All eres  +3 bits seems to do is clear up the waveform jitter.  If I have sensitivity set too low (here 50V to make it obvious), the resolution of the Math waveform is heavily degraded.  At normal sensitivity, with or without eres, the Math waveform looks fine.  I note that you're using a sensitivity of 500mV which makes the source waveforms take up a large part of the screen and so would probably look even better than the 2V I use.  I stopped at 2V only because I didn't want to change the offset of the waveforms between captures to keep them on the screen at the higher sensitivity.

It really seems that the Math is performed on the data after it has been scaled to the screen values, and so there's no way to reduce sensitivity without also reducing the quality of the Math waveform generated.   I can deal with this, but I just wanted to be sure I wasn't overlooking an obvious mistake in setup.

[tautech]

Where's the ripple on waveforms 3 and 4 coming from ?

[rf-loop]

No, I've tried setting the timebase to extreme values and it doesn't change at all.  It really does look like the Math function is working with too little vertical resolution on the source waveforms.  At the sensitivity I'm using here they look pretty pixilated as well, though the input signal is fine.

Waveforms vertical resolution come from 8 bit ADC.  ADC full scale is around 10 vertical division on display.
One ADC step is 2 display pixel. Now your scale is then multiplied by 5 (your channels are 50V div and Math is 10V div (50/10=5). So, your Math trace steps on the display are now 10 pixel height)
This same happen if you capture signal, stop scope and zoom in vertically) It do not use interpolation between math result data points or other tricks for produce more nice looking "art" image.

Now also original traces CH3 and CH4 looks smooth. These waves update rate is much higher than Math trace and there is several waveforms overlayed in every TFT frame. If you change Acquistion mode from fast (default) manually to Slow then these all waveforms are updated around same speed, one wfm one TFT frame. Very specially it can see if you change display mode to Dots and then change between fast and slow acquisition mode.

What ever you use: Trace average or ERES result is always 8bit but method is different and for different needs.  (and example some manufacturer advertise 12 bit after box car averaging. Result is 8 bit and nothing more.)

Also if use display mode Vector it is wise some times to look with interpolation Sin(x)/x on and off. (in Vector display mode. Dots mode do not use interpolation at all.

But then. Also there is possible something wrong in Math if Math sources a A and B are from different ADC groups. (CH1 and 2 is group one and CH3 and 4 is group 2 ... because there is 2 ADC's)

Math function FFT have display mode "Exclusive" and this display mode turn source display off.
I hope Siglent add this display function available also with other Math functions.
Now example with CH1 - CH2 only thing what user can do is dim A and B traces to minimum but even then they are very visible.

But, because Math is not only function where example I miss feature that I can shut off channel trace display but only display. Example some times if I need use one channel just as Ext Trig and I do not want this signal is always visible.  If Siglent develop this (and with good ergonomy-usability) but it need experienced and intelligent UI designer, not only programmer, then it also can use with some Math functions.

[StillTrying]

2) So I can't move the waveforms offscreen and if they're onscreen the display gets really cluttered.  For some types of analysis, I really don't want to see CH3-4 on the screen - it prevents me from getting a good look at the output; however,

I would think you could press STOP and then move CH3-4 off screen, - not ideal but it should leave you with just the input and MATH waveforms on screen.

[innkeeper]

Is the SAG1021 the only option compatible with the bode plotting, or can it be used with other siglent AWG's?

[tubularnut]

Is the SAG1021 the only option compatible with the bode plotting, or can it be used with other siglent AWG's?

I believe any Siglent AWG's will work. I'm using an SDG1062X, no license needed either

[GregDunn]

Tautech: it's a cheap Class D amplifier; that is the switching (PWM) signal leaking through on the output at approximately 600KHz.  Normal for low-end Class D amps.

rf-loop: yes, and thanks for the added viewpoint.  I'm using CH3-4 so the same ADC.

StillTrying: no, even in STOP mode Math takes into account the values and locations of the source waveforms.  It causes the same problem as though I were in RUN mode.   

Appreciate all the comments; I think I've figured out what's going on and will be able to deal with it now.  As rf-loop notes, there are other good reasons to be able to enable/disable trace display and it would be handy if Siglent looks at this for a future release.

[innkeeper]

Is the SAG1021 the only option compatible with the bode plotting, or can it be used with other siglent AWG's?

I believe any Siglent AWG's will work. I'm using an SDG1062X, no license needed either

very cool
i count find any write-up on it on siglents site.
i wonder if its just the X series AWG's?

[tautech]

Is the SAG1021 the only option compatible with the bode plotting, or can it be used with other siglent AWG's?

I believe any Siglent AWG's will work. I'm using an SDG1062X, no license needed either

very cool
i count find any write-up on it on siglents site.
i wonder if its just the X series AWG's?

I no longer have any pre X model AWG so I can't say for certain but as far as we know all Siglent AWG's can be tethered to SDS1*04X-E models to perform Bode plots.

This from the User manual:
http://old.siglentamerica.com/USA_website_2014/Documents/manual/SDS1000X-E_UserManul_UM0101E-E03A.pdf
P219/229
The bode plot application for the SDS1000X-E (only 4 channels scope supports this
application) controls a external arbitrary waveform generator(AWG, only the Siglent’s
arbitrary waveform generator can be supported ) to sweep a sine wave across a range of
frequencies while measuring the input to and output from a device under test (DUT). At
each frequency, gain and phase are measured and plotted on a Bode chart.

And later:
USB Connect the oscilloscope USB Host to the external AWG’s USB Device via a USB cable.
LAN Connect the oscilloscope and the external AWG to your local area network.
 If LAN is selected, press IP softkey, a dialog box named “IP” will pop up; then; turn the universal knob to enter the value. The IP is the external AWG’s IP.
 Press Test Connection softkey to check the connection.

You can do direct LAN connection but IP configuration becomes important to get exactly correct. It is much simpler through a network switch.

[innkeeper]

anyone have problems with long PSK's on wifi?
I am using a long PSK ~25 characters long with spaces in it, and it doesn't seem to be working.

[tautech]

anyone have problems with long PSK's on wifi?
I am using a long PSK ~25 characters long with spaces in it, and it doesn't seem to be working.

So I'm guessing you can't connect.
Is WiFi finding your access point with no problem ?

If you have more than one be sure to select the correct one before keying in the PSK password.
And just to check, which model USB dongle are you using ?

[innkeeper]

So I'm guessing you can't connect.
Is WiFi finding your access point with no problem ?

If you have more than one be sure to select the correct one before keying in the PSK password.
And just to check, which model USB dongle are you using ?

it's finding the access point, no problems.
yes, connecting to the correct one.
usb dongle is TL-WN725N

[tautech]

So I'm guessing you can't connect.
Is WiFi finding your access point with no problem ?

If you have more than one be sure to select the correct one before keying in the PSK password.
And just to check, which model USB dongle are you using ?

it's finding the access point, no problems.
yes, connecting to the correct one.
usb dongle is TL-WN725N

Thanks.
I'll check mine to see if there's a character # constraint/limit.

[innkeeper]

additional info.

so i created a guest network with a short password, and still, it didn't work.
i changed the guest network from WPA2 to WPA, and it connects. unfortunately, the guest network is isolated and only usable for internet access, so it's not a solution

so its coming funky with it authenticating/connecting via WPA2.

i must have 30+ devices on my network all connecting via wpa2, so i am fairly confident it is not a router issue.

[tautech]

additional info.

so i created a guest network with a short password, and still, it didn't work.
i changed the guest network from WPA2 to WPA, and it connects. unfortunately, the guest network is isolated and only usable for internet access, so it's not a solution

so its coming funky with it authenticating/connecting via WPA2.

i must have 30+ devices on my network all connecting via wpa2, so i am fairly confident it is not a router issue.

OK so it would seem you have the PSK character set correct.
Hmmm

From the datasheet:
802.11b/g/n, WPA-PSK, the adapter must be supplied by Siglent to ensure working. (yeah right, we know the gold version works !)


Does your adapter have a silver body or gold ?
The gold body TL-WN725N on the box lists WPA-PSK and WPA2-PSK capability.
The gold body version was originally the only one supported however recent FW changes allowed for silver body  TL-WN725N usage too.

Interesting, anyone else ?

[innkeeper]

OK so it would seem you have the PSK character set correct.
Hmmm

From the datasheet:
802.11b/g/n, WPA-PSK, the adapter must be supplied by Siglent to ensure working. (yeah right, we know the gold version works !)


Does your adapter have a silver body or gold ?
The gold body TL-WN725N on the box lists WPA-PSK and WPA2-PSK capability.
The gold body version was originally the only one supported however recent FW changes allowed for silver body  TL-WN725N usage too.

Interesting, anyone else ?

it has a gold body, it is a TL-WN725N V3

[17_29bis]

Hello,
I noticed a couple of things that can be confusing to new users who just started using the device.
Moment N1:

Imagine the trigger was set to channel 3:



Later you turned the channel 3 off and the trigger settings became invalid i.e. the trigger will not work although you still see on the screen the trigger info box and the trigger level icon (in blue):



One could say - the user has enough info/hints on the screen to figure out that the trigger will not work and this is true to some extend - enough if you know where to find those hints on the screen. Another way to tell the user that the trigger is basically disabled is to make  the trigger info box or the trigger level icon or the button blink (red color is great for this purpose) to immediately inform the user that the trigger is assigned to the disabled channel.

[4x1md]

anyone have problems with long PSK's on wifi?
I am using a long PSK ~25 characters long with spaces in it, and it doesn't seem to be working.

There is a bug with network SSIDs which contain spaces. The scope will see this network but won't be able to connect to it.

Siglent confirmed this bug but I don't know when it will be fixed.

My WiFi dongle was not supplied by Siglent and works fine with networks without spaces in SSIDs.

[4x1md]

I have found a new bug in bode plots.

When the waveform cursors are shown on the waveform screen, the bode cursors on the bode plot won't move.

To reproduce the bug:
1. Display a waveform.
2. Show the cursors (using Cursors button).
3. Enter the bode plot mode and build a bode plot.
4. Show the bode cursors.
5. Try to move the cursors on the bode plot. They'll not move.

To be able to move the cursors on the bode plot return to the waveform screen and hide the cursors. Return to the bode plot. Now the bode cursors will move as expected.

[bugi]

Another way to tell the user that the trigger is basically disabled is to make  the trigger info box or the trigger level icon or the button blink (red color is great for this purpose) to immediately inform the user that the trigger is assigned to the disabled channel.

Actually, if considering colors for indication of statuses, red isn't great for that particular purpose.
Red is typically meant for things that can result in damage (to living or non-living things) if not paid attention to, or for the cases that are simply disallowed (without a good reason, say, emergency break). The typical color for other kinds of warnings would be yellow.  Of course, they are not that set in stone, and what to use may depend on the context.

Other than that, in general, it would be helpful if a scope would indicate any kind of reason why something would not work (be it signal out of range, trigger channel being off, or edge trigger being driven by input set to ground, whatnot, etc.), if and when the scope can detect such a situation. I tend to bump into "why does it not show the stuff" or "why is it not triggering, signal goes right there" situations almost every time I use my scope. Sometimes wasting tens of minutes to finally figure out some obscure setting buried deep somewhere, which I had perhaps tried a little earlier and forgot I changed it.  (And I am still trying hard to make myself remember that nice button which returns to the default settings.)  (I have to slightly compensate my noobness by noting that at least for the triggering issues, they have sometimes been obvious bugs and/or limitations of the hardware. It is just sometimes difficult to figure out whether the reason is in the device or the user; in the latter case spending time to adjust settings would help, in the former it is usually a waste of time.)

[tautech]

Hello,
I noticed a couple of things that can be confusing to new users who just started using the device.

All things to new users of DSO's are confusing !

This is why the Autoset button is added.

We must remember the most powerful tool in oscilloscope use is the ..................... TRIGGER !
Learning how to use it, assign it and its advanced features are mandatory to competent use of a scope, any scope.

[17_29bis]

Other than that, in general, it would be helpful if a scope would indicate any kind of reason why something would not work (be it signal out of range, trigger channel being off, or edge trigger being driven by input set to ground, whatnot, etc.), if and when the scope can detect such a situation. I tend to bump into "why does it not show the stuff" or "why is it not triggering, signal goes right there" situations almost every time I use my scope. Sometimes wasting tens of minutes to finally figure out some obscure setting buried deep somewhere, which I had perhaps tried a little earlier and forgot I changed it.

I fully agree with bugi  although I don't wasting tens of minutes for troubleshooting of those things.

We must remember the most powerful tool in oscilloscope use is the ..................... TRIGGER !
Learning how to use it, assign it and its advanced features are mandatory to competent use of a scope, any scope.

Sorry, this is just a general statement like saying "water is wet". Sure, users have to learn how to use their DSO, DMM, to drive the car,  to respect older people etc. But its also clear that the thoroughly designed and implemented  User Interface of a device should avoid displaying incorrect/misleading information. In other words those things (users' education and proper implementation) are not mutually exclusive, they are complementary.

tautech, I have a question for you    Can you please  check the screenshot shown below and describe the signal/trace for the channel 3? Thanks!

This is why the Autoset button is added.

Life would be wonderful is the Autoset button could be a single solution for all problems but it is not.

[4x1md]

If it is to drive a non-Siglent AWG, maybe they can charge for it.

Maybe ? 
It's very unlikely command protocols will work with other brands.

When doing Bode plots the AWG is swept through many frequencies/second so commands must be correct.

Plotting bode plot with a non-Siglent AWG is possible with a protocol translation software.

At certain point after getting the SDG1204X-E oscilloscope I wanted to know if it might be possible to use the bode plot function with a non-Siglent waveform generator.

After some researching and fuzzing I wrote a program in Python which acts as a small server. The oscilloscope connects to it using LAN and the program makes it think that it communicates with a genuine Siglent AWG. The program extracts the commands sent by the scope to the generator, parses them and translates to the command set, that the connected to the PC non-Siglent AWG is able to understand.

The video shows bode plot of an LPF with R=1kOhm and C=0.22μF. On the left you may see my program running on a netbook. For the first try I took the well known JDS6600 generator which is sold on eBay/AliExpress. Later I'll add drivers for two more AWG models.

That surly will be of interest to the community.

I hope to have during the next weeks enough free time to publish the program on GitHub with detailed description on how it works.

Great work and looking forward to your further efforts. 

Finally, I published the code on GitHub:

https://github.com/4x1md/sds1004x_bode

I also started a new topic for questions and discussing:

https://www.eevblog.com/forum/testgear/siglent-sds1104x-e-and-sds1204x-e-bode-plot-with-non-siglent-awg/