Siglent SDS-1202X-e waveform issues

[JiaRen]

So recently I received a Siglent scope as a gift, it has been reported to be working just fine. When i tried to use it and hooked up to it's internal square wave generator, the waveform looked out of place. Even the compensation screw on the probe is not working.

Even if I probed my DAC that is outputing a 1khz sinewave, it also looked messy. I asked my friends that is using the same model and they stated that it is weird. One of them pointed out that it looks like its oscillating on the square wave. I tried everything, self calibration, updated the firmware to the latest on the siglent website. I seem to ran out of options to address this issue.

[bdunham7]

Try this:

1) turn scope on
2) press "Default" button
3) connect CH1 probe to the calibrator output
4) press "AUTO SETUP"

[JiaRen]

Tried that a lot of times already, still no change

[JiaRen]

I played the unit abit more and I put the memory depth to 140k, and it did an okay square wave but not clean. as soon as i go to other bit depth, the square wave is noisy. THe thing that concerned me is the frequency, it doesnt say F = 1.000000kHz but instead F > few mhz

[tautech]

I played the unit abit more and I put the memory depth to 140k, and it did an okay square wave but not clean. as soon as i go to other bit depth, the square wave is noisy. THe thing that concerned me is the frequency, it doesnt say F = 1.000000kHz but instead F > few mhz
(Attachment Link)

Set to max and ensure the trigger level indicator is within the amplitude of the waveform.

[tautech]

BTW, If you really want a full rundown on what this scope can do start here when member CharlotteSwiss orders hers:
https://www.eevblog.com/forum/beginners/what-an-oscilloscope-recommended-for-a-woman-passionate-about-electronics/msg3104228/#msg3104228

[JiaRen]

Already, initially I already did it like that, but the wave would be like this. For some reason I injected a sine wave and it would appear as square wave
 

[tautech]

Stop, take a breath.
You are connected to the probe compensation waveform, it is 1kHz at 3V
Set the scope to display it with the entire waveform within the borders of the display.

Then insert a FAT32 formatted USB stick of 8GB max size and press Print to capture the screenshot.
Add the png screenshot into Attachments and other options so we can better see the scope settings.
Be sure to have the trigger level set within the amplitude of the waveform and the easy way to do that is press the trigger level encoder which will set the level automatically to 50%.

[tautech]

Below is SDS1104X-E, the 4ch brother or SDS1202X-E. The menus, display and info tabs are very similar to 2ch X-E. Here I use 10X probe and set the input attenuation to match in the channel menu.
All my settings you need match to have the same display.

[Kean]

Already, initially I already did it like that, but the wave would be like this. For some reason I injected a sine wave and it would appear as square wave

Channel is set to 1x and 50mV/div.  You aren't going to see a full 3V signal like that.

It looks like you are using a P6100 probe.  Is it set for 1x or 10x?  Do you know the probe is good?

[JiaRen]

I see, so I can just auto setup, set the time division then take a screenshot for you?

[JiaRen]

It’s set on 1x, initially thought it’s the probes fault. I guess it’s user error now.

[Kean]

It’s set on 1x, initially thought it’s the probes fault. I guess it’s user error now.

Just make sure the channel is set the same as the switch on the probe, otherwise voltages won't be correct.

Auto setup should still be able to show the waveform, and you shouldn't have to adjust voltage or timebase to see the signal.

If you have another probe, you might also want to try swapping them to see if that makes any difference.

[JiaRen]

I dont know what is going on, when I pressed autosetup, nothing will come up. Only when I start touching the voltage division and the time division, the wave would only appear. So when I replicate your settings, nothing appears.

[JiaRen]

Both probes same thing, auto setup wont show the waveform until i touch the voltage and time division. the 1x and 10x are set correctly.

[JiaRen]

My friend that sent me the gift said that the Main board must have been damaged during shipment. Best bet now is to get a replacement board from siglent.

[tautech]

Ok so have you checked channel 2 ?
You will need to reassign the trigger to it too so to get a stable waveform.

[JiaRen]

yep, same issue. Set the trigger already aswell.

[tautech]

Have you swapped probes ?
Just a piece of wire from the probe compensation terminal into the channel input should display the correct waveform with a 1V/div and 500us/div.

Is there any sign that the input BNC's have suffered an impact ?

[JiaRen]

Yep, swapped probes, but no havent tried a piece of wire into the BNC, I'll try that.
 THe BNC connector has no sign of impact, so it was weird.

[tautech]

Yep, swapped probes, but no havent tried a piece of wire into the BNC, I'll try that.
 THe BNC connector has no sign of impact, so it was weird.

P6100 probes right ?
Used in 1x or 10x mode ?
In 1x mode the compensation trimmer has zero effect, only in 10x mode.....but we need a scope to properly display a compensation waveform.

[JiaRen]

Yep, P6100, it was in 1x mode. Here this is the pic for the piece of wire going into the inputs from the compensation terminal

[tautech]

Yep, P6100, it was in 1x mode. Here this is the pic for the piece of wire going into the inputs from the compensation terminal (Attachment Link)

Let me contact Siglent tomorrow and see if they have any comments as to what to check/do next.

It seems unusual that it would display a corrupted waveform at the wrong settings and nothing at the right ones. 
You've done a Default, yes or no ?

[JiaRen]

Yep, I've hit default. Although this is my first oscilloscope, I have operated other scopes before at my work place. I instantly know something is wrong if the wave looked like that, one more comment is that when I checked a 1khz sinewave, it would appear as a square wave aswell. So, now im completely out of options. 

Then, ill wait on what to do next. Thanks.

[rf-loop]

Please tell oscilloscope FW version and HW version etc info from oscilloscope Info screen.


1.
Do factory default:   Push Save/Recall function key, then select Recall menu and select Type: "Factory Default" and then "Press to recall".
And please do not now hit Autoset button or Default button at all now in or between any next steps!



In your first message you tell you have done Selfcal. We need be sure it have done right way.

2.
So please do it again (after 30minute warm up).
Be sure that NOTHING is connected to oscilloscope any inputs. Just open and empty BNC connectors.
Let Selfcal run without touching scope inputs. Just follow it running to 100% and after it is ready and OK,  push  Run/Stop button.
(if it stuck before 100%,  note it and do not continue any next steps, it is then waste of time)



Just for repeat that make sure it is stored in the "backbone": Please do not now use Autoset or Deafault at all in or between any next steps!  : D

3.
Insert USB flash (for images)
Push then "Print" button for image to USB. (yes I want see also this image)

Based to your previous messages looks like you do not have any reliable signal generator. If you have please tell if you have, and if you also have then BNC cable.
(Also I do not trust your probes at all at this time.)

But before it,  some easy "desert class" tests without any extra instruments or accessories like probes etc.

4.
Take around 15-20cm suitable wire what other end can insert to CH1 input BNC center contact only (without damage it) but what make good reliable contact. 
Because there is now factory defaults in use we know exactly what all settings are now.
Do not change anything but said things.

Change now only these: Vertical: select 100mV/div and Horizontal: set 10ms/div
Keep other stripped end of wire in your hand.
Push "Print" button for image to USB.

5.
Change only Vertical: 200mV/div
Keep other end of fire in your hand
Push "Print" button for image to USB.

6.
Change only Vertical: 2V/div
Keep other end of fire in your hand
Push "Print" button for image to USB.

7.
Change only Set Vertical 1V/div and Horizontal scale to 10ms/div  and adjust Trigger level to +1.5V 
Connect this wire from CH1 center  to  probe calibration pulse output  "1kHz" (upper connector). Be sure wire do not short circuit to GND.
Push "Print" button for image to USB.


Show these images.