New Scope Opinion - Siglent SDS2304X or... - Page 1
Forum section: electronics / testgear

author: Shuggsy
author_rank: Regular Contributor
timestamp: February 22, 2018, 03:40:39 am
content: TL;DR:I'm currently looking at the Siglent SDS2304X but would love to hear opinions about scopes which still meet my must-haves (below) and are around my budget ($2500 US preferred, could go up to ~$3000 US with good reason). Alternatively, is it worth my time to wait to see if new scopes are announced in the first half of this year? I could wait, but then I wouldn't be able to use the scope on my current projects...It's been some time since I posted on the forum, but I wanted to get your opinions on a new scope purchase I'm looking to make. I'm in the US Southeast (Georgia) and I've got ~$2500-3000 US to put toward a new scope. I would much prefer to stay around $2500, but if there's a really compelling scope which is ~$3000 then I may be able to push the budget. Currently the best/fastest working scope I have (I've got two busted Tek 475A's as project scopes waiting to be repaired...) is a 100 MHz Rigol 1052E. I've made some upgrades to other bits of test gear but I'm looking for a major upgrade to my scope. Intended use is slightly higher-end hobby stuff. I'm starting to work with some FPGAs and want to be able to probe some of the memory interfaces and other faster signals than I can currently capture.General requirements (must-haves):- 4 analog channels- 16 digital channels- Serial decode (at least SPI, I2C, CAN, and UART)- At least 300 MHz analog bandwidth- Fast enough waveform capture rate to get a "digital phosphor" kind of display (ie. graduated intensity levels)- Easy screen capture (LAN preferred, USB stick is ok)- Simple math functions- Large (at least ~7") display- Enough memory depth to capture longer signals at full sample rate (maybe 10 Mb+?)Bonus points:- Built-in 50 Ohm terminations- Dedicated trigger input- Waveform search functionality- Advanced math (functions on functions) and/or a half-decent FFTBased on my target budget and after reading around the web and on the forum, I came on to the Siglent SDS2304X as the current frontrunner. It appears to hit all my must-have requirements, is within my budget (with all options and the current 30% off promotion), and at least has the 50 Ohm terminations as a bonus. I've seen the nctnico vs. tautech views on GW Instek vs. Siglent (), respectively, and I have to say that considering all I've read I still prefer the Siglent for my uses. That said, I'm willing to listen if I end up with a better scope for my needs.Rigol was my first thought, but they unfortunately don't seem to have a scope that hits all my must-haves in my budget. The MS1000Z series hit most except for the bandwidth (very important), the 2000 series didn't have 4 analog channels (also very important), and the 4000 series was well above my budget for my desired feature set.I saw the R&S RTB2000 but unfortunately missed the launch deal so it's out of my budget when spec'd to my feature set.The other big(ger?) players like Tek and Keysight just seem to be out of my budget for my feature set. Looks like they aren't even really trying to compete in this class and price range.Another option that occurred to me was to just sit on eBay and hope to get a deal on a low-ish end Keysight DSOX3000A (or similar - suggestions welcome)... maybe attempt to hack whatever scope it is up to get into my specs if that's possible... but it's all a bit of a gambleand I'd be hosed if anything went bad.I've also heard rumors that new scopes may come out this spring? Maybe just wait a bit?I'd love to hear any inputs or opinions!

author: tautech
author_rank: Super Contributor
timestamp: February 22, 2018, 08:01:49 am
content: Quote from: Shuggsy on February 22, 2018, 03:40:39 amAnd Dedicated trigger input, something that's not overly common on a 4ch DSO.Do you have the full handle on the current promo ?Simply, it's in 2 parts; BW upgrade so you'd only pay the SDS2204X price and then add the two LA options (HW and license) to get the AWG and Decode options additionally for free.Unfortunately Power Analysis is not part of any current promo.It comes with 10x only auto sense probes as standard so if you use 1x probes at all you'd maybe want to get switchables as an option. The 10x probes are much nicer than switchables and a bit smaller form factor.QuoteWhat PC OS will you be using for the LAN screen captures ?If Linux you might want to have a look here:https://www.eevblog.com/forum/testgear/open-source-lxi-tools-and-liblxi-v1-0-released-for-gnulinux/There's more in the App Notes page:https://www.siglentamerica.com/application-notes/sds2000x-series/QuoteYep, not much happening here with 2kX models but the new Siglent kid in town is much better featured in this regard. SDS1004X-E models but only to 200 MHz. Dual ADC's like the 2kX models but only half the sampling speed at 1GSa/s. Most likely not sufficient BW for your needs.Any SDS2304X screenshots you'd like please ask.Good luck with your search.

author: nctnico
author_rank: Super Contributor
timestamp: February 22, 2018, 05:13:12 pm
content: I'd still recommend to take another look at the GW Instek MSO2000E series. It has better FFT, more advanced math, input filtering and full memory decoding. The main problem with the SDS2000X is that it has a very slow processor so things like math, hi-res, decoding are implemented in a limited way. AFAIK it doesn't have a search function at all.For looking at high frequency signals you will be better of with an (additional) older 500MHz or 1GHz scope from Tektronix, Lecroy, Agilent, etc. Bandwidth increases the price of a new oscilloscope exponentially so having a good 100Mhz to 200MHz allround oscilloscope and an (older) special purpose one gets you the best of both worlds but it just isn't combined in one device.

author: tautech
author_rank: Super Contributor
timestamp: February 22, 2018, 09:03:28 pm
content: Quote from: Shuggsy on February 22, 2018, 03:40:39 amThis use case is always problematic when pushing past maximum BW.There's a couple of 'work arounds' to get the info you seek.Slow the clock down to speeds where BW roll off is more acceptable and 'representative' measurements can be taken.Use better than std probes, higher BW and/or active probes. Most often just one high spec probe is needed.If high BW needs are infrequent and experience is adequate the above can be a viable option.

author: rsjsouza
author_rank: Super Contributor
timestamp: February 22, 2018, 09:23:26 pm
content: If you are looking used,this onechecks several boxes of your requirements. It has 30 days warranty.

author: nctnico
author_rank: Super Contributor
timestamp: February 22, 2018, 10:55:13 pm
content: Quote from: rsjsouza on February 22, 2018, 09:23:26 pmBut no peak-detect which IMHO is mandatory on a general purpose DSO.

author: rsjsouza
author_rank: Super Contributor
timestamp: February 23, 2018, 01:21:54 am
content: Quote from: nctnico on February 22, 2018, 10:55:13 pmI personally don't use peak detect that much, but each to its own. Regardless, at the OP's price point there is a huge number of great options in the used market.

author: Shuggsy
author_rank: Regular Contributor
timestamp: February 23, 2018, 03:39:22 am
content: Thank you everyone for your inputs! More opinions welcome - my knowledge of what I should really expect for my $2.5-3k US budget is still rather limited. To respond directly to a few things...Quote from: tautech on February 22, 2018, 08:01:49 amI missed that! I expected to see it on the front and completely discounted the connections on the back. That certainly makes it more appealing. What are the specs of the external trigger input? 50 Ohm, bandwidth, etc.? I looked through the SDS2kX manual but apparently missed this.Quote from: tautech on February 22, 2018, 08:01:49 amPerhaps not. My "30% off promotion" note came from theSiglent America websitewhich says "Limited Time Offer - Buy More and Spend Less - Save 30% on Siglent's SDS2000X Oscilloscopes." If I stick with the SDS2304X then I'll also use the Saelig discount from the forum!Quote from: tautech on February 22, 2018, 08:01:49 amWindows, although the Linux tools are interesting. I could make either work in most cases.On a similar note, is the SDS2kX series able to save the actual waveform data to USB or out the LAN? It might be beneficial to be able to perform extended analysis on the signals outside of the actual scope.Also, just to confirm, getting the MSO/LA option comes with the actual logic probes, correct?Quote from: nctnico on February 22, 2018, 05:13:12 pmMany thanks for the input. I went and had another look at the MSO2000E series. They're not bad scopes, but the 300+ MHz bandwidth just seems like a requirement for me for my price range. I'll admit, it's a bit of an arbitrary requirement, but 200 MHz just seems slow for a general purpose scope these days...Still, your suggestion of an older high BW scope + a more general purpose scope is very interesting. I may look into that later if I really get into a more regular need for that kind of speed. For now, I should be able to get by with what I'm trying to get out of this new scope.Quote from: rsjsouza on February 22, 2018, 09:23:26 pmYou know, I looked on eBay some for scopes I was semi-familiar with in this price range (Keysight 3000 series primarily), but you raise a very good point. Something I'd like to ask you or anyone else willing to chime in on is: What scopes should I really be looking at that meet my specifications and might be in my budget on eBay? For that matter, are my requirements reasonable for my price range? Should I expect less? Or more?Again, thanks for the input everyone!

author: Shuggsy
author_rank: Regular Contributor
timestamp: February 23, 2018, 03:51:49 am
content: Answering my own question because I'm apparently blind while looking over the datasheet...The EXT trigger input appears to have:- 1Meg Ohm and 50 Ohm terminations- DC, AC, GND coupling- Same max input, isolation, and attenuation options as the regular channels- Edge triggering onlyAll in all, much better than not having one!

author: tautech
author_rank: Super Contributor
timestamp: February 23, 2018, 04:28:15 am
content: Quote from: Shuggsy on February 23, 2018, 03:39:22 amEither I think, certainly to USB and in several formats. (check manual P150, linked below)In the Save menu there's all the format options.They're listed in the User Manual P150:http://www.siglentamerica.com/wp-content/uploads/dlm_uploads/2017/10/SDS2000X_UserManual_UM0102X-E02A-1.pdfQuoteYes, that's the HW part: SPL2016https://www.siglentamerica.com/wp-content/uploads/2017/11/PARTS-LIST_SPL2016.pdfThe SW license is needed too: SDS 2000X LAEdit to add:Check the App notes for further info:http://www.siglent.com/ENs/prodcut-pxzl.aspx?id=1243&tid=1&T=2

author: nctnico
author_rank: Super Contributor
timestamp: February 23, 2018, 10:04:15 am
content: Quote from: Shuggsy on February 23, 2018, 03:39:22 amDo yourself a favor and test drive the MSO2000E and the SDS2000X yourself. Be sure to dig deep into the advanced features like decoding, triggering on decoding, math, etc to see if they meet your needs. In this price range you can't just buy something based on a datasheet.QuoteKeysight scopes are nice but the 'low end' models all suffer from really short memory. The 4Mpts models have 1Mpts or less in real use scenarios because the memory is shared between the channels and half is used for double buffering. Another problem with the older models is that they have a lot of noise on the signal. I used to own an Agilent MSO7104A but surprisingly the GW Instek GDS2204E (which I bought as a bring-along-to-customers scope) proved to be much more useful for day to day work.

author: rsjsouza
author_rank: Super Contributor
timestamp: February 23, 2018, 01:03:01 pm
content: Quote from: nctnico on February 23, 2018, 10:04:15 amThis is the best advice anyone here can give you. Only you are capable of skimming through the scope and highlighting the different aspects that really matter to you.Quote from: nctnico on February 23, 2018, 10:04:15 amAs Nico mentioned, if deep memory is important for you to capture and analyze these very long datastreams, then Keysight is out of reach for your price range - all 2000, 3000 and 4000 series have very limited memory. You can partially workaround this with advanced or protocol triggering, but that may not be enough for your needs. They are hackable, though.As for LeCroy, stay away from their entire WaveAce line of products. Also, feedback from others around here on their Wavesurfer 3000 is pretty bad (you can search around here), but I would at least try one if possible. If your work requires a lot of math and signal processing operations on the signal, LeCroy bundles a lot on its hardware.Rigol DS4000 does the job quite well for my needs, but it is not super stellar in FFT or protocol decoding (if you are into that - sorry, I am typing this on a tablet which does not show your original post so I could be sure) and has a few minor quirks. Going for it is that, as with all Rigols, is hackable which can yield 500MHz, 4ch and complete suite of protocols at very large memory (140Mpts) at quite a reasonable price. If you can get a demo unit, I think it is worth trying.Unfortunately I don't know Siglent's or Instek's product lines, but what I gather from years of discussions here is that:- Siglent is quite popular and competes with Rigol for features and bundling, but had severe issues in the past with unsolved firmware bugs. They recently released a number of interesting models to compete with the lower end of the spectrum (Rigol DS1000Z and DS2000) thus may not be what you are looking for but it may replace your Rigol with advantages.- Instek is not very popular and, because it is not hackable, it ends up positioned a bit higher priced than Siglent or Rigol. Some folks around here praise its polished firmware and speed to correct bugs.Offers:Rigol clearance bin:https://www.rigolna.com/clearance/LeCroy Wavesurfer 44XS-A with make an offer button:https://www.ebay.com/itm/Teledyne-LeCroy-WaveSurfer-44XS-A-400MHz-2-5GS-s-4Ch-Oscilloscope/152918870005?hash=item239aacc7f5:g:1QwAAOSwBoxajyrCLeCroy Wavesurfer 454 with options (ask the seller) and make an offer button:https://www.ebay.com/itm/LeCroy-WaveSurfer-454-500MHz-2GS-s-4Ch-Oscilloscope-Calibration-Options/152862454708?epid=2169752282&hash=item23974ff3b4:g:4XAAAOSwmuVaV8Qk

author: nctnico
author_rank: Super Contributor
timestamp: February 23, 2018, 03:56:19 pm
content: Another oscilloscope brand to look at is Yokogawa. The newer LCD based models also support protocol decoding and triggering but not all of the ones on Ebay have the protocol decoding options and you'd have to ask your local dealer if these can be enabled for the particular model you have an eye on.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: February 23, 2018, 04:09:27 pm
content: Quote from: rsjsouza on February 23, 2018, 01:21:54 amI always have PD on - avoids missing small pulses/glitches, and when doing general "probing around looking for something" jobs, means you can just leave it on a fairly slow timebase but still see things like short UART data bursts. Definitely wouldn't consider a scope without it.

author: rsjsouza
author_rank: Super Contributor
timestamp: February 23, 2018, 05:36:24 pm
content: Quote from: mikeselectricstuff on February 23, 2018, 04:09:27 pmThanks for the comment. So that presupposes a fast acquisition system (wfm/s) to be effective, right? If so, in this regard the Keysights would be unbeatable.

author: nctnico
author_rank: Super Contributor
timestamp: February 23, 2018, 05:51:19 pm
content: High waveforms/s are way overrated. peak-detect + roll mode is often much more interesting to catch random events because you capture 100% of what happens. Deep memory allows to zoom in and still get lots of detail on what is actually going on.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: February 23, 2018, 06:31:32 pm
content: Quote from: rsjsouza on February 23, 2018, 05:36:24 pmThat's not so much about wfm/sec, as that's down to trigger frequency - it's about memory, as at slower timebases it samples as fast as it can and displays the peak values for each displayed horizontal pixel. Bear in mind that though the KS memory is small compared to some, it always uses all of it with no speed penalty (subject to channels etc.), whearas most others have some tradeoffs between memory size and speed, and can get sluggish when using large memory depths

author: rsjsouza
author_rank: Super Contributor
timestamp: February 23, 2018, 08:17:44 pm
content: Quote from: nctnico on February 23, 2018, 05:51:19 pmI didn't overrate it - Keysight doesHowever, from yours and Mike's replies I get what the usage scenario is. That reminded me of anancient threadwhere this was discussed.

author: tautech
author_rank: Super Contributor
timestamp: February 24, 2018, 07:09:51 am
content: Quote from: Shuggsy on February 23, 2018, 03:39:22 amHad a chance to fire my SDS2304X up for this screenshot of the Save menu:

author: tautech
author_rank: Super Contributor
timestamp: February 24, 2018, 09:24:53 am
content: While I was at it, 100mV into 50from HP sig gen to find -3dB point. BNC cable connection.Initially set up @ ~150 MHz and showed ~3 mV high @ 300 MHz.Then all the HP could give.....~510 MHz (as rated) and on the way the scope frequency counter spluttered and started running lower from ~415 MHz.

author: KeBeNe
author_rank: Regular Contributor
timestamp: February 25, 2018, 04:12:19 pm
content: and here a hardware modified SDS 2104X

author: rf-loop
author_rank: Super Contributor
timestamp: February 25, 2018, 05:29:29 pm
content: Quote from: KeBeNe on February 25, 2018, 04:12:19 pm

author: Shuggsy
author_rank: Regular Contributor
timestamp: March 10, 2018, 03:19:21 am
content: Just wanted to provide a small update and give my thanks again for those who provided their inputs!Based off all the replies, it certainly seems like there's a number of options around my price point all with their own tradeoffs. Most would meet the needs I know of today, but nothing really stood out as the clear winner to me (at least for my own assumed requirements and projected needs). I was originally planning to get the scope for some upcoming projects of mine. However... rather than pick one now, I'm going to hold off until I hit a point in the projects where I really need to get the improved performance from the new scope. This will give me a chance to see if any crazy deals come up like R&S's release promotion for the RTB2000 series or if something special hits eBay. Who knows, maybe I'll hit the jackpot onAgilent'sKeysight'sscope monthWave!In the interim, the capability I really* need is capturing 8 digital data lines + some address lines at once. I have a Saleae Logic 8 (and really like it), but that won't cut it for the amount of lines I want to capture. So I'm getting a Saleae Logic Pro 16. I've used one for a few projects at work as well and it should serve my needs very nicely. With the analog capture, I may even be able to use it as a makeshift MSO for my project... (essentially looking at the inputs/output of a couple old school audio DACs)So, again, thanks again to all that replied. Your replies and my own research which spun out from reading through your comments helped me get up to speed on the current landscape of the scope market around my price point.*Alright, yes, I could fudge this by taking multiple captures with a common trigger between the captures... or using my existing Rigol to add a couple channels... or some other kludge... but capturing all lines at once is far more convenient