Atten ADS1102CAL - trigger uncertainty/jitter problem?

[dmderev]

Any owners of ADS1102CAL - please respond. I just got this oscilloscope and initially was impressed by its functions. But I have one disappointment when trying to look at 10-30MHz signals. It looks that it has uncertainty of trigger point - the waveforms are displayed in two different positions with 10ns offset - they come out randomly and it visually looks like a jitter. It is VERY visible and annoying on 25, 10 and 5ns/division timebase settings. It is much less visible on slower timebases, although data analysis shows that it is there too. It does not depend on the mode of triggering - the waveforms captured in single shot also come out two ways - with 10ns offsets from the trigger edge. Usually, there are more captures with one position of the edge, but sometimes the distribution is 50/50.
It looks that it is either a bug in the capture logic, or a bug in software.

Please respond if you experienced similar issues - they are very clear if you look at the output of a crystal oscillator running at 20-50MHz...

This is an unfortunate and very annoying problem with otherwise decent instrument.
Does anyone have a schematics or any other documentation beyond the manual?

Thanks!

[JuliusL]

Hi

I have the Atten ADS 1102CML, I have the same problem. I wrote an e-mail to ATTEN
about it, and they responded that whit in 6-8 weeks a new firmware upgrade will be available.
I like Atten , I had all the "big" player, like Rigol, Owon, I had to send it back.
Hantek is a really good scope, but the firmware has some bugs. I decided to pick Atten due to the
experiance I had after testing them. Atten not perfect, but for general use, you get what you pay for.
Please e-mail Atten about the problem. I done it about 3 weeks ago. The more complain the better.
It is a software problem, and they know about it.

JuliusL

[saturation]

I'm not sure I'd hold Atten in this high regard.  True they do reply, but what few posts are on eevblog about Atten replies suggests while they do reply, the reply can simply be false or misleading information. 

https://www.eevblog.com/forum/product-reviews-photos-and-discussion/atten-atf20b-teardown/

Now, on scopes, maybe newer models they have improved their quality and design but see these old threads.

If you look at their other products like 858D reworkstation or lab PSU, there are sometimes serious errors in build quality.  So, in all, in at least a sample of their products, I'm not sure Atten as a company and thus all its products would not be high on my list.

https://www.eevblog.com/forum/product-reviews-photos-and-discussion/atten-dso-1060c/msg32199/#msg32199


In this thread an analysis of its build and design by tinhead:

https://www.eevblog.com/forum/general-chat/siglent-sds1102cm-and-easyscope/

[saturation]

If any user does get a firmware update and improves this scopes functionality, please let us know.

I think unacceptable bugs are those which affect the scopes measurement capacity, you can't second guess it.  Triggering, jitter, and sampling artifacts appear in Atten models in the videos linked, and not in Rigol.

For the Rigol, eevblog users have been dissecting it since 2009, many of the users who posts on it are very skilled, so you know its been tested to perform to it specs.

Now, on scopes, maybe newer models they have improved their quality and design but see these old threads.

That's why i simply don't buy a rework station from them , i buy the original Yihua 858D+ .
Also their PSU's looks ditchy to me .

[Colin]

contact Siglent directly, they are the ODM of ATTEN.

I heard they already make new firmware to slove this problem.

[saturation]

I recently located a detailed review of the Atten.  Unfortunately, it doesn't give a substantial technical analysis, so I've emailed him if he could answer some key questions. The reviewer is a professional EE with credentials more than enough to give a substantial review:

Photos:
http://home-and-garden.webshots.com/album/581243391pwaPvH 

Text:
http://www.epinions.com/content_578790395524?sb=1

Who the author is:

http://h-e.com/dane-e-ericksen-pe

[dane1234abc]

I have updated my Webshots album to show the results of measuring the bandwidth of my Atten ADS1102CAL digital storage oscilloscope.  Thanks for asking, I probably would never have bothered to measure the BW otherwise, since my application was in the 150 kHz range.  A plot of the results is attached.  For full details, visit my updated Webshots album.  The BW measurements are at the start of the album.

[saturation]

Thanks dane1234abc, that's undeniably a >= 100 MHz response.  That easily puts to rest questions about its frequency response.

[nbinont]

It looks that it has uncertainty of trigger point - the waveforms are displayed in two different positions with 10ns offset - they come out randomly and it visually looks like a jitter.

I, too, am experiencing this problem (trying to look at a 50MHz clock and 12.5MHz square wave from a FPGA). I can also confirm that the 2nd errant trigger happens as a 10ns early trigger.

It does not happen all the time, but does reliably happen eventually.