Siglent SDS1000X and (MSO) SDS1000X+ series oscilloscopes

[cjm]

Yes, ch2 also looks good. 

[Orange]

Tautech, did you get any response from Siglent on how to correct this issue in a SDS1102X ?

I rather don't want to send it back to the factory. I have all the tools to do the repair myself. Just need to know what parts need to be replaced.

As one can see in several topics of the Siglent scopes, the LF compensation of the Siglent scopes is not to good. In fact it is very poor. The upcoming reviews of any new Siglent scope should have a close look at this LF compensation, with and without probes.

[tautech]

Tautech, did you get any response from Siglent on how to correct this issue in a SDS1102X ?

I rather don't want to send it back to the factory. I have all the tools to do the repair myself. Just need to know what parts need to be replaced.

As one can see in several topics of the Siglent scopes, the LF compensation of the Siglent scopes is not to good. In fact it is very poor. The upcoming reviews of any new Siglent scope should have a close look at this LF compensation, with and without probes.

Sorry I haven't investigated any LF internal compensation issues for SDS1kX models, only X-E.
Are both channels the same, and probes too ?
I'm guessing that screenshot is with probes.
What is the signal source ?

If we refer to cjm's post, IMO that's the wisest course of action:

Ok, I've received a reply from the dealer :

...
we already had a few cases where the SDS1000X devices have a weakness at low frequencies (<300Hz) AND low voltages (<500 mV).
If the deviation is greater then 3% (this is what is specified in the datasheets) we can send the device to Siglent for adjustment.
Unfortunately there is no other way to solve this.
...

So my SDS1202X will be going on a little trip! 

For your location the work will be done in Hamburg not at the factory in Shenzhen or maybe even your local dealer.
Yeah I know it's a curse but at least Siglent are prepared to put this right.

I'll point someone to your post to get a speedy solution for you. Expect PM contact.

Thinking ahead, you want to make sure (if indeed the mainboard gets replaced) they have one on hand to ensure a quick turnaround for you.

[Orange]

Tautech, did you get any response from Siglent on how to correct this issue in a SDS1102X ?

I rather don't want to send it back to the factory. I have all the tools to do the repair myself. Just need to know what parts need to be replaced.

As one can see in several topics of the Siglent scopes, the LF compensation of the Siglent scopes is not to good. In fact it is very poor. The upcoming reviews of any new Siglent scope should have a close look at this LF compensation, with and without probes.

Sorry I haven't investigated any LF internal compensation issues for SDS1kX models, only X-E.
Are both channels the same, and probes too ?
I'm guessing that screenshot is with probes.
What is the signal source ?

If we refer to cjm's post, IMO that's the wisest course of action:

Ok, I've received a reply from the dealer :

...
we already had a few cases where the SDS1000X devices have a weakness at low frequencies (<300Hz) AND low voltages (<500 mV).
If the deviation is greater then 3% (this is what is specified in the datasheets) we can send the device to Siglent for adjustment.
Unfortunately there is no other way to solve this.
...

So my SDS1202X will be going on a little trip! 

For your location the work will be done in Hamburg not at the factory in Shenzhen or maybe even your local dealer.
Yeah I know it's a curse but at least Siglent are prepared to put this right.

I'll point someone to your post to get a speedy solution for you. Expect PM contact.

Thinking ahead, you want to make sure (if indeed the mainboard gets replaced) they have one on hand to ensure a quick turnaround for you.

Yes both channels have this.
This is without probes
Source is a SDG1032X, and on my Agilent DSO7054 all is fine, so are all my other scopes :-) So it is definitely the Siglent scope
It is the same issue as posted in a few postings back.
The scope was purchased from Batronix. I have not yet contacted them, in the hope I can fix it myself.

[Orange]

Thanks to Tautech and Jie from Siglent, I was able to fix the LF distortion issues on my SDS1102X. Jie (from Siglent) did write me, and advised to replace R430 and R502 in the analog front-end section with an 23.7k 0.1% resistor, 25PPM, 0603 SMD form factor
The original resistor was 10k

I tried this in the first place, but then the slope of the distortion became reversed... :-(
So I decided to sit in the middle, and the one type resistor I had in stock was 18k. It was however a 0805 type. Anyhow on the pictures you can see that it is mounted sideways.
The LF compensation or distortion is now perfectly corrected on both channels.
Mind you that you need to do an self-calibration after the fix, because the DC levels become shifted when you change the resistors. Self calibration corrects this nicely.

If you want to do this yourself, you need good SMD assembly skills. The pictures taken might give you the impression that this is all big stuff to work with :-)

Thanks Siglent and Tautech for your help !




 

[tautech]

New firmware for the 1kX/X+ series.

Version: v1.1.1.2.15R10
http://siglenteu.com/gjjrj-xq.aspx?id=4045&tid=15

2Mb

Changelog
1. Fixed the read data bug while STOP from ROLL mode, fixed the bug of CSV timestamp error in ROLL mode.
2. Optimize self-calibration for Channels

[Orange]

New firmware for the 1kX series.

Version: v1.1.1.2.15R10
http://siglenteu.com/gjjrj-xq.aspx?id=4045&tid=15

2Mb

Changelog
1. Fixed the read data bug while STOP from ROLL mode, fixed the bug of CSV timestamp error in ROLL mode.
2. Optimize self-calibration for Channels

Firmware works OK, just do a SelfCal after the upgrade