Siglent Technologies SDS1202X-E 200 mhz Digital Oscilloscope 2 Channels

[13hm13]

I purch'd this scope about 2.5 years ago. Haven't used it much because I'm a bit addicted to my old analog Tek 465.

That said, if any of you own this scope, share your thoughts. For example, how does it compare to similar priced Rigol models? How about day-to-day reliability?
Please share any tips and tricks with this scope.

One strange "anomaly" (??) of the Siglent I ran into was that if I swapped my probe from Ch1 to Ch2 -- the probe tips and gnd on the same DUT -- Ch2 did not lock trigger. I don't know how to do that.
If I have both Ch1 and Ch2 probes -- say comparing two logic-chip outputs -- then Ch 2 does lock (as does Ch1).

Have look at this waveform displayed on my Siglent. It is MCK output from an audio USB-I2S adapter (see bottom photo; the Owon meter was used in another experiment). I am using the alligator probe for gnd.

Anything look unusual?

[coromonadalix]

Scope fFirmware is up to date ?

[TheDefpom]

If you are triggering from a different channel then you need to select which channel that is in the trigger menu.

Also set the trigger level to get the best rising edge, where it is in the image could result in irregular triggers.

[BillyO]

You also shouldn't really switch probes between channels because they will need to be re-compensated.  Probe compensation is channel is specific to each channel.

Wouldn't make a huge difference, but for the sake of best performance and all ..

[13hm13]

If you are triggering from a different channel then you need to select which channel that is in the trigger menu.

Also set the trigger level to get the best rising edge, where it is in the image could result in irregular triggers.

Yeah, for some reason I can't permanently set EDGE trigger for both channels. If I turn on edge for one channel, the other channel trigger is null. And so I must manually do it. Weird.

Also very weird is the cold start ...

If I've had the unit off -- unplugged - - for, say  over a few hours or longer, and re-start, I have very rough 15-20 minutes of 'settling-in time'. Nothing locks (trigger), As I rotate the vertical or  horiz., or other buttons, I can monetarily see the correct signal.  This even applies to something as simple as the 1k square wave /ground tab on the from. The first test of 'scope reliability.
And then -- after 20 min or so -- normal. Very weird!
I have not used this 'scope enough to establish some sort of what-is-normal behavior. And of course, the 'scope is out of warranty! Life lesson: open and test your new instrument thoroughly and extensively upon delivery! It might come outta the simulation factory ... possessed.

[tautech]

If you are triggering from a different channel then you need to select which channel that is in the trigger menu.

Also set the trigger level to get the best rising edge, where it is in the image could result in irregular triggers.

Yeah, for some reason I can't permanently set EDGE trigger for both channels. If I turn on edge for one channel, the other channel trigger is null. And so I must manually do it. Weird.

You're in the DSO world now and not all CRO features migrate to DSO's, ALT triggering a fine example.

Also very weird is the cold start ...

If I've had the unit off -- unplugged - - for, say  over a few hours or longer, and re-start, I have very rough 15-20 minutes of 'settling-in time'. Nothing locks (trigger), As I rotate the vertical or  horiz., or other buttons, I can monetarily see the correct signal.  This even applies to something as simple as the 1k square wave /ground tab on the from. The first test of 'scope reliability.
And then -- after 20 min or so -- normal. Very weird!

1/ Previously you have been asked but haven't responded which firmware version is installed ?
To be up to date Sys Info in the Utility menu should display Version V1.3.26
2/ This DSO should perform perfectly from the moment it is powered ON on one proviso, it has previously been powered OFF correctly.
That is with a 2s press of the power button to allow the instrument to power down in a controlled manner and save all previous settings.
If by chance firmware is up to date and scope is still playing up press Default to return the instrument to factory settings.

I have not used this 'scope enough to establish some sort of what-is-normal behavior.

Yes, that is evident and you really need spend more time with it to learn all its features.

First for me is what I see on the display which tells me heaps about how you have it set and how you have used it.
We are here to help and first exercise is to grab a USB stick and learn how to capture screenshots to it by just pressing the blue Print button. These captures are just a few 10's of KB not some 2.5 MB monster done with a camera.
Cleverly done you can capture an appropriate menu too to convey to us more info on how you have the scope set up.

Learning to use the power of the scope starts with setting channel input attenuation and probe attenuation correctly
so measurements are correct which removes the need for mental arithmetic on the fly to arrive at waveform values.
Typically we set the probe and channel attenuation to 10x and leave it there. Each probe also needs to be assigned to a channel by fitting the colored rings and in 10x mode compensated. 

Looking forward to seeing more of your work.

[sonpul]

Anything look unusual?

No. This is what the signal looks like. For example, I looked at Pi2Aes
And with raspberry pi4

[13hm13]

If you are triggering from a different channel then you need to select which channel that is in the trigger menu.

Also set the trigger level to get the best rising edge, where it is in the image could result in irregular triggers.

Yeah, for some reason I can't permanently set EDGE trigger for both channels. If I turn on edge for one channel, the other channel trigger is null. And so I must manually do it. Weird.

You're in the DSO world now and not all CRO features migrate to DSO's, ALT triggering a fine example.

Also very weird is the cold start ...

If I've had the unit off -- unplugged - - for, say  over a few hours or longer, and re-start, I have very rough 15-20 minutes of 'settling-in time'. Nothing locks (trigger), As I rotate the vertical or  horiz., or other buttons, I can monetarily see the correct signal.  This even applies to something as simple as the 1k square wave /ground tab on the from. The first test of 'scope reliability.
And then -- after 20 min or so -- normal. Very weird!

1/ Previously you have been asked but haven't responded which firmware version is installed ?
To be up to date Sys Info in the Utility menu should display Version V1.3.26
2/ This DSO should perform perfectly from the moment it is powered ON on one proviso, it has previously been powered OFF correctly.
That is with a 2s press of the power button to allow the instrument to power down in a controlled manner and save all previous settings.
If by chance firmware is up to date and scope is still playing up press Default to return the instrument to factory settings.

I have not used this 'scope enough to establish some sort of what-is-normal behavior.

Yes, that is evident and you really need spend more time with it to learn all its features.

First for me is what I see on the display which tells me heaps about how you have it set and how you have used it.
We are here to help and first exercise is to grab a USB stick and learn how to capture screenshots to it by just pressing the blue Print button. These captures are just a few 10's of KB not some 2.5 MB monster done with a camera.
Cleverly done you can capture an appropriate menu too to convey to us more info on how you have the scope set up.

Learning to use the power of the scope starts with setting channel input attenuation and probe attenuation correctly
so measurements are correct which removes the need for mental arithmetic on the fly to arrive at waveform values.
Typically we set the probe and channel attenuation to 10x and leave it there. Each probe also needs to be assigned to a channel by fitting the colored rings and in 10x mode compensated. 

Looking forward to seeing more of your work.

No, I have not updated FW.

Today, I had the unit unplugged for a few hours. Came back to it, plugged it in, put the probes (1x) on the 1khz sqr wave/gnd test tab (see photos).

Got weird NON-square 1khz form for a few minutes. And it settled  to a nice, clean square. This is what I was referring to before. The cold-start weirdness can vary quite a bit -- waves look strange or can't lock, etc.

Un-updated firmware causing this garbage --- really ? Even so, what a major SNAFU in quality control.

[tautech]

Please please please learn how to take USB screenshots so we can see your settings otherwise we cannot offer proper advice.

[13hm13]

Please please please learn how to take USB screenshots so we can see your settings otherwise we cannot offer proper advice.

What a weird comment! How else would one know where my probe was plugged into. Or that I really own the 'scope. Screen shots are easy to steal from Google images.
Come on!
 You  really are completely clueless as to what the cold boot issue is, right?

[tautech]

Please please please learn how to take USB screenshots so we can see your settings otherwise we cannot offer proper advice.

What a weird comment! How else would one know where my probe was plugged into. Or that I really own the 'scope. Screen shots are easy to steal from Google images.
Come on!
 You  really are completely clueless as to what the cold boot issue is, right?

Don't call me clueless sonny as I've sold more of these scopes than you might imagine !

Again, we can't see your settings in the piss poor pics you took due to the lighting glare.
Please take a screenshot to USB with the blue print button then we can see what's going on.

[13hm13]

Please please please learn how to take USB screenshots so we can see your settings otherwise we cannot offer proper advice.

What a weird comment! How else would one know where my probe was plugged into. Or that I really own the 'scope. Screen shots are easy to steal from Google images.
Come on!
 You  really are completely clueless as to what the cold boot issue is, right?

Don't call me clueless sonny as I've sold more of these scopes than you might imagine !

Again, we can't see your settings in the piss poor pics you took due to the lighting glare.
Please take a screenshot to USB with the blue print button then we can see what's going on.

What a weird comment! How else would one know where my probe was plugged into. Or that I really own the 'scope. Screen shots are easy to steal from Google images.
Come on!
 You  really are completely clueless as to what the cold boot issue is, right?

[2N3055]

Please please please learn how to take USB screenshots so we can see your settings otherwise we cannot offer proper advice.

What a weird comment! How else would one know where my probe was plugged into. Or that I really own the 'scope. Screen shots are easy to steal from Google images.
Come on!
 You  really are completely clueless as to what the cold boot issue is, right?

Don't call me clueless sonny as I've sold more of these scopes than you might imagine !

Again, we can't see your settings in the piss poor pics you took due to the lighting glare.
Please take a screenshot to USB with the blue print button then we can see what's going on.

What a weird comment! How else would one know where my probe was plugged into. Or that I really own the 'scope. Screen shots are easy to steal from Google images.
Come on!
 You  really are completely clueless as to what the cold boot issue is, right?

 

Do you need help or you just enjoy this kind of conversation....?

You need to work with people that are trying to help you.. Sort of help them to help you..

That being said, please apply newest firmware for your scope. Manufacturers make fixes and upgrades and sometimes that is all that needs to be done to fix something.

Second, how do you know it isn't the probes that is problematic ? 1X/10X probes can have noisy switches and also cable and BNC can have bad contact.

Does the overshoot that is visible gradually (slowly) sets to normal squarewave or it is distorted for few minutes and then suddenly switches to proper squarewave ?

Is problem visible only on CH2 ?

[rf-loop]

It looks that @13hm13 have latest FW (it is SDS1202X-E).


I recommend (because @13hm13 talk about "cold start" problem)...  right now, the first thing to do is to rule out all other factors that  may affect the matter except the oscilloscope itself. So it need investigate without probes. (And next "desert method" because I do not know what tools @13hm13 have available)

Perhaps most simple thing is: Just single wire from Probe compensation output (1kHz "square") to both input BNC center tab (do it so that contact is reliable but do not damage BNC center). (no need separate GND wire, it is connected internally and is ok for this purpose.)

Then do many all kinds of cold starts etc and watch results (you can example keep it in the fridge, for example, and you'll get a bit more of a thermal gradient there when it starts up and warms up.)
You can also use even infinite display persistence setting so that if any short-term or slow changes these also stay visible on screen.)

And then, please display results to us (oscilloscope screen image (png)) if there any weird things visible.

(your previous image looks like just as typical very badly uncompensated 10:1 probe or somehow failed probe)



If in this test can not find any problem.

Then next step is look your probes...  these have really LOT of higher failure rate that these scopes. (I have never seen any failed SDS1202X-E and I have some experience about (## pcs) these started from the time Siglent have started manufactured this model. But I have seen several failed PP215 probes. Probes are just consumables like lamps and car brake pads. They are also cheap. They can in no way be compared to some of the professional Tektronix measuring heads costing hundreds of euros. )

But now we first need to find out if the problem is either inside the oscilloscope or for some reason or another somewhere outside it.

[BillyO]

You  really are completely clueless as to what the cold boot issue is, right?

WE all are, to be honest.  The main reason is you are not following people's suggestions and giving them the information they need to help.

BTW, Tautech is a Siglent dealer.  He has considerable first hand experience with these scopes and a direct line to Siglent to get any hard questions answered.  Being flippant with him might not be your best approach.

Every single person on this site knows full well what the compensation signal is and what it is used for.  One thing it is not usually used for is probes set on x1.  It is there to adjust the compensation capacitor in the probes for proper response to a square wave at 10x.

It would help tremendously if you did a proper screen shot (insert USB stick, press blue "Print" button, and attach the file to this thread so that we can see how the scope is configured.

As 2N3055 suggests, this could be caused by a faulty probe.  Try fiddling with the 1X/10X switch when you see the problem.  Or tapping gently on the probe itself.

[TimFox]

Before I retired, I was surprised at how several junior engineers, who were otherwise quite competent at their jobs, did not understand CRO calibrator outputs and probe compensation adjustment.

[13hm13]

Cold boot this morning. Not as distorted as yesterday, but not SQUARE given the probe is connected to Siglent's own, pure 1k sqr generator tab.

This is the ENDS issue.

Have it both ways, folks, as your are deflecting! But concentrate on the ENDS, not the MEANS: This issue ain't about the USB capture So don't let your dream get distracted

============
MEANS: iPhone capture:







=============
MEANS: USB "Print" capture











=============

EDIT:

I just noticed that for all the images above, my probe switch was on 10x while the scope was MENU-set to 1x. So that may have caused this morning's issue.
Returning the probe to 1x made waveform look normal (see below)

This looks better, but the Siglent has been warming up for about half hour now, so the issue may very well cont. to exist???


The iPhone capture supports my point that USB Print is not a major issue; in fact, it may be the better storyteller.

[BillyO]

Did you do the compensation adjustment on your probes in 10X mode?

[rf-loop]

Your explanation and imges tell that you have not adjusted probe LF compensation. (Probe 10x aka 10:1)

Of course when probe is 1x square looks quite ok because when probe is set for 1x this LF compensation do not affect anything. (how you set oscilloscope input probe factor do not matter in this, only what matter is probe itself)

But when probe is set for 10x then also this compensation need adjust. In your pictures it is now very clear that it is not adjusted ok and you need do it. You , user, are responsible about it, not Siglent.
You need adjust it so that bottom and top is as flat as possible.

If you swap probe to other input also then this compensation need check and adjust if need.  Because inputs are not perfectly same (capacitance may differ as can see also in data sheet).

Then. Everyone knows that user manuals are only for dummies and us old people.
Of course, this way one can indirectly reveal that one haven't read the user manual. In first hand, of course, is important to barking that Siglent is complete shit. One could also sometimes ask the mirror.

[tautech]

This looks better, but the Siglent has been warming up for about half hour now, so the issue may very well cont. to exist???

Unknown just yet but thank you for some decent imagery. 

I strongly suggest you follow rf-loop's instructions as he knows these scope even better than I.

Display/Persistence = Infinite will show what a square wave looks like as the unit warms up.
Use the probe compensation output and as rf-loop says there is not need for a GND connection and even just use a short length of soft wire.
Recommend beforehand to do a Default on the scope and then only adjust the timebase and V/div for the capture although you may need the scope to fully cool again in order to capture this drift you have seen.

[13hm13]

Thanks for everyone's feedback.

It's important to keep the MAIN issue the forefront: the cold-boot issue.

It was presented earlier in this thread here:

https://www.eevblog.com/forum/testgear/siglent-technologies-sds1202x-e-200-mhz-digital-oscilloscope-2-channels/msg4711016/#msg4711016

Notice the distorted 1k sqr waveform. The probe's own switch was on 1x, as was the Siglent's menu-setting (1x). And I've had prev. cold-boot issues that I did not image.
This unreliability reduces my confidence in the day-to-day operation of this 'scope .... and, perhaps, of Siglent's overall QC standards. See my OP.

I do not have reliability issues with my other scope-in-the-house, the Tek 465. All orig. 1976 components inside; electro caps orig AFAIK. When I purch'd from eBay (2008), it was sold for $50 non-functional from US Navy labs. One Tant. cap brought it back to life with a great trace --- no issue with it ever since.

About the cold-boot issue with my Siglent .... as I noted earlier, it has less than 4-5 hours total use time since purchase in mid 2020.
Working on audio gear -- especially audiophile gear -- and some computer stuff, I have noticed weird reliability issues that go away magically after the device has attained some use hours. No sure about this settlement process ... e.g., current travelling thru new traces, wires, etc, smoothing and "sanding" out the path until the electrons "flow" smoothly and reliably. Very mystical ,the Simulation is

[tautech]

Thanks for everyone's feedback.

It's important to keep the MAIN issue the forefront: the cold-boot issue.

It was presented earlier in this thread here:

https://www.eevblog.com/forum/testgear/siglent-technologies-sds1202x-e-200-mhz-digital-oscilloscope-2-channels/msg4711016/#msg4711016

Notice the distorted 1k sqr waveform. The probe's own switch was on 1x, as was the Siglent's menu-setting (1x).

You have been asked to test again without the probe with a piece of wire or even with a Tek probe.
We need to eliminate probes as the cause.

[13hm13]

Did you do the compensation adjustment on your probes in 10X mode?

No! And yes, this cleaned up what I reported earlier today. So I am making some progress 

Cold-boot reliability still on wait-n-see ...

[2N3055]

Did you do the compensation adjustment on your probes in 10X mode?

No! And yes, this cleaned up what I reported earlier today. So I am making some progress 

Cold-boot reliability still on wait-n-see ...

Unfortunatelly, you didn't clear much. You keep repeating same sentences and randomly test some stuff nobody asked you..
Please answer the questions:

1. Is this cold start problem you see only on CH2 ?
2. If you connect 1x probe on "warm" scope and now see it correctly, don't touch anything and shutdown scope. Leave it for few hours (you said that is needed for it to act up).  Then start it up and verify if signal is distorted.
3. If signal is distorted, how long it takes to "clean up"? Is it gradually going to normal or it snaps back in instant at one moment?

[JeremyC]

Did you do the compensation adjustment on your probes in 10X mode?

No! And yes, this cleaned up what I reported earlier today. So I am making some progress 

Cold-boot reliability still on wait-n-see ...

Did you processed self-calibration? If not then please do, the process is described in the user manual.