Siglent SDG1032 as bad as rigol DG812?

[csuhi17]

DG912Pro
In its settings, I could not find one that would start with an active output, and I could not detect an abnormal wave when it was switched on.
no problem with normal shutdown.

when cutoff the main, it produces similar waves on the active output.

Pictures 3 and 5 with 50 ohm termination
Pictures 2 and 4 are without 50 ohms.

[eTobey]

I just tried to see, when the sinewave amplitude would decrese with rising frequency: It did increase to 4.17V amplitude, with a set up amplitude of 3.3V.
Am i missing something?

Are you sampling a 30MHz sine wave at 100ks/s?

No, i sampled a frequency sweep of a sine wave with 100ks/s. I did it again with 10Ms/s, and it makes no difference.

no problem with normal shutdown.

If you call an exceeeding of a level of about 3-4V not a problem, then i wonder, on what circuits you work, that dont have a problem with this.

How does this look with a 3.3V level? How do both channels look then?

[csuhi17]

no problem with normal shutdown.

If you call an exceeeding of a level of about 3-4V not a problem, then i wonder, on what circuits you work, that dont have a problem with this.

How does this look with a 3.3V level? How do both channels look then?

Maybe I misunderstood your question.
When the channel is active and I press the power button and press restart or shutdown, the output waveform is the image of R1.

There is only a problem with it in the event of a power failure.
Which could be solved with an uninterruptible power supply.

This is the Pro version, not the older one. DG912 Pro

And R0 is the 3.3V square wave.
CH2 with 50 ohm termination.
Without CH3 50 ohms.

[rf-loop]

Could you please do the same measurement at power up? One of the things that must be tested on all signal gens during reviews: what happens at power up/shut down. A bad design could kill your DUT.
To SDG1000X owners, could someone please do same measurements on your unit?
The signal gen may change waveform/frequency on power down but not go higher than set amplitude/offset. Ideally it should just cut out.
On power up, I expect exactly 0 volts until I press CH1/2 on buttons.

Too much expectation for a >300 bucks device...

I might not even use this on my circuit and send it straight back...


Picture of SDG 1032X on turning off:

SDG1062X  Power button shut OFF when

Ch1 1kHz square 0-5V
Ch1  50ohm (SDG), Ch1 in oscilloscope 50ohm

and  Ch2  5Vdc out.
Ch2   HiZ (SDG)   and Ch4 in oscilloscope 1Mohm
(of course SDG hardware output impedance is always 50ohm)

Both channels direct connect with ~1m Suhner RG223/U

Scope Trig: Ch1, Edge, Rising, Normal



Where is the problem?


SDS3104X HD

[eTobey]

Where is the problem?

The Problem is, that limits were exceeded.

You obviously havent tried much with it. It seems to only happen on high level. Turn it off on high level.

[2N3055]

Where is the problem?

The Problem is, that limits were exceeded.

You obviously havent tried much with it. It seems to only happen on high level. Turn it off on high level.

What high level?

You used 4V he used 5V...
If you use 10V (max) then there cannot be higher pulse...

I suspect there is something in your setup that shoots in inductive spike when you forcefully shut off device...
Maybe ground loop of sorts..

[rf-loop]

Where is the problem?

The Problem is, that limits were exceeded.

You obviously havent tried much with it. It seems to only happen on high level. Turn it off on high level.

Do you really want to embarrass yourself at this point too?

At least if you're starting from scratch to judge what I've done for testing this device for as long as this model has been around and the same goes for some previous models as well. In that case, you're guaranteed to bump your head into an old pine tree.
I think it is now better I'll stop feeding the Troll.

[Martin72]

Profile-->Modify Profile-->Buddy/Ignorelist-->Edit...

[eTobey]

Where is the problem?

The Problem is, that limits were exceeded.

You obviously havent tried much with it. It seems to only happen on high level. Turn it off on high level.

Do you really want to embarrass yourself at this point too?

At least if you're starting from scratch to judge what I've done for testing this device for as long as this model has been around and the same goes for some previous models as well. In that case, you're guaranteed to bump your head into an old pine tree.
I think it is now better I'll stop feeding the Troll.

I was not referring to the device itself, or the topic. I was referring to this issue. Mind the language barrier, and that i sometimes choose the wrong words.

This issues seemingly only happens, when there is a high level.

[eTobey]

I suspect there is something in your setup that shoots in inductive spike when you forcefully shut off device...
Maybe ground loop of sorts..

There is not much setup:
Gen -> allig. clips -> probe -> scope

[Mortymore]

Are you referring to some overshoot when the generator is turned OFF with the outputs still on, right?

It seems that it could happen depending were the square wave is caught at power off. Sometimes it doesn't happen, sometimes overshoots up, other down.







Anyway, I suppose that the ON/OFF output buttons serves a purpose, and that doesn't happen when they're used

EDIT: It would be so much easier for everybody if at least you had the trouble to proper stand your case with adequate description and images. After all you have the devices.

[temperance]

That what you are seeing is probably a common mode transient caused by you switching of the function gen with the power switch. You will probably see the same signal even with the output disabled.

Infact, let me try that. Yes, it is a common mode transient caused by the almost infinity fast opening and closing times of mechanical switches.

@ eTobey

your problem has nothing to do with a language barrier. It's the non stop bashing. For example the tittle of this topic:

Siglent SDG1032 as bad as rigol DG812?

-You could state: Weird signal on SDG1032 output when switched on and off.
-In your post you explain in a proper technical way the problem. Instead you scream high and low, insult people and don't provide a proper context.

In the end after the dust has settled and it turns out to be your fault your next step is bashing the manual.

Go and think for a while where this common mode noise is coming from and why your scope is displaying this signal (You might learn something very valuable and something you might find useful one day). What are the rise and fall times of a mechanical switches?

EDit: something to make you think a little harder and to mess with your mind in a positive way:
connect a shorted probe to the signal gen BNC GND. Set the scope to something like 5 µs and 1 V div. normal trigger 0.5 V. Switch the function gen on/off a few times and observe what happens.

[nctnico]

That what you are seeing is probably a common mode transient caused by you switching of the function gen with the power switch. You will probably see the same signal even with the output disabled.

It is too slow to be a common mode transient. Those are typically in sub-microsecond time spans. What you see in the screenshots is typical for less than optimal power-supply sequencing at power down.

[2N3055]

That what you are seeing is probably a common mode transient caused by you switching of the function gen with the power switch. You will probably see the same signal even with the output disabled.

It is too slow to be a common mode transient. Those are typically in sub-microsecond time spans. What you see in the screenshots is typical for less than optimal power-supply sequencing at power down.

Except that nobody can reproduce it in such form.
And you that don't own that AWG (or even similar one) are making conclusions based on some scope images that are made God know how. Scope was sampling at 2Ms/s using Peak detect mode. Any high frequency would be sampled as outside envelope, not as base frequency..

I don't have SDG1000X either. But believe RF-Loops results, who made VERY comprehensive tests at the time. He knows it inside out.
If some specific test could be defined he could run it.

But the way I see it, whatever is on the scope screen has more to do with what and how was tested.
You and I might disagree from time to time but one thing I agree with you 100% is your signature.

OP should connect scope to an AWG directly, use full memory, maximum sample rate, and try then.
To exclude DUT, it's power supply, connection to computer ground via ICP connector etc etc..
When something is wrong, you reduce variables. Eliminate sources of confusion. Reduce problem complexity.

[eTobey]

EDit: something to make you think a little harder and to mess with your mind in a positive way:
connect a shorted probe to the signal gen BNC GND. Set the scope to something like 5 µs and 1 V div. normal trigger 0.5 V. Switch the function gen on/off a few times and observe what happens.

I will do this, but only if you tell me, what you expect to see/happen.

And dont anybody else dare to answer this request!

[eTobey]

But believe RF-Loops results, who made VERY comprehensive tests at the time. He knows it inside out.
If some specific test could be defined he could run it.

Well even the best specialist can miss a detail... and that detail was the "high level" which i could not explain to you.

You and I might disagree from time to time but one thing I agree with you 100% is your signature.

I am happy, that you realized, that you can see yourself on what ever side you want. That is the beauty of this signature. ;-)

OP should connect scope to an AWG directly, use full memory, maximum sample rate, and try then.
To exclude DUT, it's power supply, connection to computer ground via ICP connector etc etc..
When something is wrong, you reduce variables. Eliminate sources of confusion. Reduce problem complexity.

The OP never had the DUT never connected to that AWG, as he is not that stupid to hook it up to an unknown device.

But tell me, how should full memory and sample rate change anything on that signal???

[eTobey]

Are you referring to some overshoot when the generator is turned OFF with the outputs still on, right?

It seems that it could happen depending were the square wave is caught at power off. Sometimes it doesn't happen, sometimes overshoots up, other down.

(Attachment Link)

(Attachment Link)

(Attachment Link)

Anyway, I suppose that the ON/OFF output buttons serves a purpose, and that doesn't happen when they're used

EDIT: It would be so much easier for everybody if at least you had the trouble to proper stand your case with adequate description and images. After all you have the devices.

Portugal 1:0 Finland 

[temperance]

I just tried to reproduce the problem captured by eTobey but the sig gen. is a SDG2042. It does a clean shut down every time. The only artifacts one can see are caused by common mode currents. But they look different. (There is nothing connected except an oscilloscope short to GND).

So maybe I'm wrong.

I will do this, but only if you tell me, what you expect to see/happen.

Something like this

[rf-loop]

Are you referring to some overshoot when the generator is turned OFF with the outputs still on, right?

It seems that it could happen depending were the square wave is caught at power off. Sometimes it doesn't happen, sometimes overshoots up, other down.



Anyway, I suppose that the ON/OFF output buttons serves a purpose, and that doesn't happen when they're used

EDIT: It would be so much easier for everybody if at least you had the trouble to proper stand your case with adequate description and images. After all you have the devices.

I want look this bit more when I have time for it.
If it is very "random" after shut off with power line, I want still catch it (these upper level "peaks" in end.)

The signal outputs should be cut off before the collapse of the operating voltages progresses to a level where the device starts to run out of control.


How was signals connected. (in your image looks it looks like well connceted with external 50 ohm and coaxial but still I like facts and not my quess.)
What is your SDG Hardware version.

[temperance]

I'm able to catch this when the sig gen is starting. That's when some relays are switching just after boot.

As soon as you attach even the smallest load onto the output, nothing of this can be seen at the output. Nothing abnormal.


Edit: this is an SGD2042

[nctnico]

I just tried to reproduce the problem captured by eTobey but the sig gen. is a SDG2042. It does a clean shut down every time. The only artifacts one can see are caused by common mode currents. But they look different. (There is nothing connected except an oscilloscope short to GND).

So maybe I'm wrong.

Your screendump looks like what I'd expect where it comes to connecting / disconnecting mains. Also keep in mind that your SDG2042 is a totally different instrument and there might be different hardware versions as well.

[eTobey]

I just tried to reproduce the problem captured by eTobey but the sig gen. is a SDG2042. It does a clean shut down every time. The only artifacts one can see are caused by common mode currents. But they look different. (There is nothing connected except an oscilloscope short to GND).

So maybe I'm wrong.

I will do this, but only if you tell me, what you expect to see/happen.

Something like this

Do you expect this to happen when turning it off and turning it on?

[eTobey]

If it is very "random" after shut off with power line, I want still catch it (these upper level "peaks" in end.)

The signal outputs should be cut off before the collapse of the operating voltages progresses to a level where the device starts to run out of control.

Its not really random. Just set up a 99% duty square and you should get it quite easy. I had it the first time just now.
 
I got the probe now directly inserterted into the BNC, and it looks pretty much the same. See picture.

[eTobey]

I'm able to catch this when the sig gen is starting. That's when some relays are switching just after boot.

As soon as you attach even the smallest load onto the output, nothing of this can be seen at the output. Nothing abnormal.


Edit: this is an SGD2042

I would not care about a one time noise burst of about 80mV ;-)

[Mortymore]

...

How was signals connected. (in your image looks it looks like well connceted with external 50 ohm and coaxial but still I like facts and not my quess.)
What is your SDG Hardware version.

Hi rf-loop

The AWG is an SDG1032X (upgraded to SDG1062X), SW version: 1.01.01.33R8 ; HW version: 02-01-00-24-00
The cables used are a very old pair of RG-58/CU with 1m aprox.
Only one feedthrough 50Ohm terminator was used at CH1 of the scope, were the square wave was applied.

The over and undershoot captured in previous images, doesn't always happen. I could have posted a similar picture as yours, but it would have been redundant.
I assume that the "spikes" seems to be controlled somehow, because there are flattops, when a differential voltage goes over roughly 1.5V.

If any further info or diligence from me is needed, please inform.