Siglent SDS2202X-E known bugs? - Page 1
Forum section: electronics / testgear

author: rcbuck
author_rank: Frequent Contributor
timestamp: August 20, 2020, 04:45:53 pm
content: I was going to purchase an SDS1202X-E but have decided for the slight extra money to purchase the SDS2202X-E. Mainly I am looking at the extra memory in the 2202. Are the still know bugs in the 2202 or have the firmware updates corrected all of them?A question for tautech (or anyone else who can do it). In this post:https://www.eevblog.com/forum/testgear/ideal-oscilloscope-for-audio-applications-(fft-and-fra)/msg2761546/#msg2761546you said you could post screenshots. Is it possible for you to post a screenshot of a 60 kHz sine wave with a capture time of 5 seconds and 10 seconds? I want to see what the sine wave looks like when captured over those length of time.Thank you.Edit: corrected title "know bugs" to "known bugs"

author: tautech
author_rank: Super Contributor
timestamp: August 20, 2020, 08:48:06 pm
content: Development has mostly mirrored the SDS1104X-E that while SDS2202X-E has just 2 channels the feature set is identical between these series.Last firmware release was just a short while back in July and posted here:https://www.eevblog.com/forum/testgear/siglent-sds2000x-e/msg3121698/#msg3121698New products held in stock might not have this firmware installed so check any purchase and update if necessary.I'll try and find time to do a capture later today......bump me if I forget.

author: tautech
author_rank: Super Contributor
timestamp: August 20, 2020, 11:47:09 pm
content: Quote from: rcbuck on August 20, 2020, 04:45:53 pmWaveform reproduction is indeed impacted on by timebase used for long captures but to some degree it can be mitigated by the settings used.An assortment of screenshots follows of 60 KHz sine as asked for using dedicated Roll mode and then auto Roll mode which does slightly better as it offers deeper memory and hence more sample points for better waveform reconstruction. Yet Siglent have imposed a limit on capture magnification at these slow Roll mode timebase settings to preserve reconstruction quality.BTW, the 2 GSa/s and 28 MPts that SDS2kX-E use are settings dependent however these are always visible so the user can decide on settings that produce best results.The last screenshot is a free running screenshot (not Stopped) of the 60 KHz sine.Signal source via BNC = SDG6202XScope used SDS2352X-E 500ms/div = 7s capture

author: rcbuck
author_rank: Frequent Contributor
timestamp: August 21, 2020, 03:14:09 am
content: tautech, could you do me one more favor? Would you please run the first 5 second test again and after it stops, change the secs/div to 10 usecs? I want to see if the sine wave looks as good as the 5th screen shot when it does a 5 second capture. Looking at the 1st screen shot it appears that the wave will still be clean.Sorry, I should have mentioned that in the beginning. If the scope will capture 5 seconds @ 60 kHz and I can then change secs/div and see the individual sine waves, I will be ordering the scope tomorrow.Thank you.

author: tautech
author_rank: Super Contributor
timestamp: August 21, 2020, 06:03:14 am
content: Quote from: rcbuck on August 21, 2020, 03:14:09 amIt won't be, period. Captures fix the available sample points to that moment in time.The 5th image was a free running trace so the samples are continually overlaid on the display whereas a Stopped and magnified capture has far lesser data points, only those at time of capture.The 4 first images are from Roll mode then Stopped and magnified and dedicated Roll mode offers way less mem depth in which as the magnified trace shows a limit to the magnification.I didn't explore the limits to magnification in auto Roll mode however with far more memory available I suspect you can go all the way to theirfastest setting, 500ps/div.Nope, 500ns see below.I'll check but not for a bit as it's dinner time here so gimme an hour or 2.Anyways, all this certainly demonstrates the advantages of a deep memory DSO.

author: tautech
author_rank: Super Contributor
timestamp: August 21, 2020, 08:45:56 am
content: rcbuckI'm capturing at 500ms/div which x14 divisions = 7s. Next slowest setting is 200ms/div = 2.8s full display width so not used.Auto Roll mode for the first 2 images with max magnification of it in the 2nd screenshot.However I discovered Auto Roll mode captures allows for use of the zoomed (dual) timebase (whereas dedicated Roll mode doesn't) in which the whole capture is accessible via the H Pos control. Also auto Roll mode allows for deeper magnification than permitted in dedicated Roll mode.The last 3 showing use of zoom on the capture at timebases to max zoom of the capture.

author: rcbuck
author_rank: Frequent Contributor
timestamp: August 21, 2020, 03:03:18 pm
content: tautech, thank you for the additional screen shots. Everything looks good and the scope will certainly accomplish what I want it to do.Specifically, I am looking at the WWVB 60 kHz transmitter signal. I want to see the phase change that haapens when the data changes from a 1 to 0 or 0 to 1. According to their documentation that should happen at the zero crossing of the sine wave.

author: tautech
author_rank: Super Contributor
timestamp: August 21, 2020, 05:45:40 pm
content: Quote from: rcbuck on August 21, 2020, 03:03:18 pmYou might be able to find that phase change using the Search feature and if it's regular enough even with a live (uncaptured) waveform.Little example of using Search here:https://www.eevblog.com/forum/testgear/siglent-sds1204x-e-released-for-domestic-markets-in-china/msg1370717/#msg1370717