Good value oscilloscope with strong analytical features? - Page 1
Forum section: electronics / testgear

author: Hagrid
author_rank: Contributor
timestamp: September 07, 2018, 09:13:18 am
content: Hello everyone,it seems to me that all powerful analytical features are available exclusively on high end scopes.By this i mean features like more than one math trace (ideally at least 4 and math on math traces), measurements with strong statistical analysis possibilities like histograms and a high customizability of those.I have seen the release of the new rigol ds7000 series which seems to feature some details i am interested in, however it is a really expensive device. I also don't really need super high sampling rates and bandwidth. The 100MHz of my DS1054Z are pretty much all i need. Another scope series i looked at is the Rohde & Schwarz RTE series. These devices are basically out of the price range i am looking at, but seem to have a load of features i would love to see at lower end scopes. The high resolution is also really neat, but i guess i am already asking for to much.The R&S RTE scope looks actually way better in terms of price/performance than the DS7000 in my opinion.I even could get away with a 2 channel scope in 90% of my use cases. A scope with a good support to export data to be further processed by Matlab is an option also, however i think in this case the throughput of data would be pretty high. I have seen some Lecroy scopes supporting this (XDEV option), but only on their high end devices.So is there anything i might have missed and should have a look at? It feels like i am pretty much left with waiting what there is to come with future releases.Greetings, Hagrid

author: nctnico
author_rank: Super Contributor
timestamp: September 07, 2018, 09:40:49 am
content: This might be interesting given your requirements: The GW Instek GDS2000E / MSO2000 / MDO2000 have a free form math trace (which offers more flexibility than multiple stacked math traces) and statistical analysis on segmented data. On top of that they have fast data transfer over the network in case you want to do analysis on a PC. If you want to do off-line analysis then the R&S RTB2000 or RTM3000 may be of interest as well because these have 10 bits ADCs.

author: 2N3055
author_rank: Super Contributor
timestamp: September 07, 2018, 09:55:29 am
content: Hi.You can get older used high end Lecroy. One option that is often ignored is Picoscope.Regards.

author: Mr Nutts
author_rank: Regular Contributor
timestamp: September 07, 2018, 10:06:20 am
content: Quote from: Hagrid on September 07, 2018, 09:13:18 amSounds familiarI doubt you'll find what you're looking for in any of the cheaper scopes, no matter if Rigol Siglent GW Instek or from the big brands, they all more or less offer the same basic math only.Have you considered going 2nd hand?After reading a lot about what a more sophisticated DSO can do I bought two Lecroy Waveruner LT scopes (a LT264 which is 350MHz and a LT374 which is 500MHz), which now thanks to the LeCroy option recovery thread have all interesting options. My scopes are from 2001 but their math capabilities are fantastic, there are dozens of functions which can be stacked (math on math), advanced FFT up to 25M including phase, demodulation, you name it. On top of that are a wide range of triggers for pretty much everything. The only thing I sometimes miss is serial bus decoding.There's also the Wavepro 900 which is the bigger brother of the waveruner and which offers higher bandwidth, sample rates and memory.I'm currently looking at a Lecroy Windows scope (X-Stream?). I was told from a very reliable source that shall not be named that if I needed the more flexible triggers of my LT scopes then I should avoid Waveruner 6000 and Wavepro 7000 as both offer only a limited set of triggers and look at a Xi or Xi-A instead. But these are still outdside my budget range so I think I'll stick with my LTs for now

author: Fungus
author_rank: Super Contributor
timestamp: September 07, 2018, 10:33:09 am
content: Quote from: Mr Nutts on September 07, 2018, 10:06:20 amAnd I can't imagine any marketing people thinking, "What if we put all that stuff in a $400 device? Would that be good for profits?"Your only chance is data capture and analysis on a PC, but ... given that even the cheapest oscilloscopes can acquire 1Gb/sec of data then that's probably not going to work out either.Bottom line: You're going to a car dealer and asking for Ferrari performance with a Ford Fiesta pricetag.

author: Hagrid
author_rank: Contributor
timestamp: September 07, 2018, 11:30:06 am
content: Thanks for the responses! I will take a look at the GW Instek and Picoscope devices to get a complete overview.Quote from: Mr Nutts on September 07, 2018, 10:06:20 amThis sound exactly what i am looking for, thanks for the hint! Do you mind if i pm you for a few specific questions?

author: MrW0lf
author_rank: Frequent Contributor
timestamp: September 07, 2018, 12:16:45 pm
content: You can look here for various trickery that can be done on Picoscopes using built-in math. For example Ive done software ADC (feeding digital channels in from analog ch on non-MSO), software DAC (feeding up to 16bit analog thru MSO port), crude math-based FRA etc.https://www.eevblog.com/forum/testgear/picoscope-2000/For fully custom external processing (MatLab etc) look for USB 3 scopes because they offer much higher realtime streaming speeds in range of couple hundred MSa/s.Example:VirtualMSO, signal fed in from analog channel on non-MSO scope:Brown line is analog input. Green line is gone thru discretization process. Black ones are extracted bits.

author: macboy
author_rank: Super Contributor
timestamp: September 07, 2018, 02:03:38 pm
content: Quote from: Mr Nutts on September 07, 2018, 10:06:20 amI bought a used Lecroy WavePro 960 (ca. 2001, 2 GHz, 16 GS/s, 16 MS memory) with lots of software options including Wave Analyzer Pro and DDA. I paid just a little over $1k USD about 2 years ago. Deals can be had if you watch ebay/etc closely.The Wave Analyzer Pro gives quite advanced analysis including histograms, various FFTs, and jitter analysis. It can do four math waveforms, including math on math waveforms, which is essential in my opinion. Lecroy sold a version of this scope called J-260 which seems identical to a WavePro 960 w/WAVAPRO except for a few front panel quick-access buttons. Mine also has the DDA option, which is the Disk Drive Analyser, providing a series of tools to analyze PRML signals etc. Again, the Lecroy DDA-260 is essentially a WavePro 960 DDA option and a different front panel. These were state of the art scopes not long ago, and while their features and capabilites are well behind current state of the art scopes, they are well ahead of budget scopes. You can get a lot for your money. I've heard that their software options are now "restorable" with tools for doing so floating around out there somewhere. I haven't done so as mine is nearly fully optioned anyway.Downsides of this older tech include large size, a lower resolution screen (it is a 10.4" color TFT, but only 640x480), slower CPU (so update rates and math waveforms are slower), and a interface that is notably more clumsy than modern DSOs. It also lacks USB for saving waveforms, though there are other ways such as LAN, GPIB, {cough}floppy{cough}, and compact flash card (in a PCMCIA adapter). Note not all of these have the LAN or PCMCIA. Oh, there's the option of a hard copy too. Press a button, and abuilt inthermal printer makes a printout of the waveform, optionally with much higher resolution than the screen - don't accidentally print a large waveform at maximum resolution, you will get averylong scroll of paper.edit:Check out the manual at:http://cdn.teledynelecroy.com/files/manuals/wp_om_revc.pdffor a good description of analytical capabilities.

author: Hagrid
author_rank: Contributor
timestamp: September 07, 2018, 10:08:10 pm
content: Hello again,i had a look at the different devices suggested here. Thank you again all for the information. The GW Instek looks like a neat scope, but i think it isn't such a significant upgrade. Instead of getting the 1054Z i should have gotten this in the first place maybe. The Picoscope devices also look really promising. I really like the fact that you don't have to pay for any additional features. It looks like you pay quite a bit for the compact size. This isn't a huge constrain in my case, so i don't know if i want to pay for it.The older Lecroy devices look like pretty much what i was looking for. I was reading a lot of data sheets today to compare specs and get some insight in the features. The LT series and the wavepro 900 series seem to have all the features i would love to get my hands on. The wavepro 7000 series is also quite appealing but the price is somewhat high.All of them have different memory options. It looks like these are hardware options? I assume this is all offline and no newer versions has been released to prevent unintended upgrades? The Wave Analyzer Pro option is really what i am looking for. It looks like the LT Series offers the extendet math functionallity as an option, however it looks like being included in the wavepro.Edit: I forgot a question: Is there anything particular to watch out for? Like dead backup batteries causing the calibration data to be lost or more serious issues.

author: DaJMasta
author_rank: Super Contributor
timestamp: September 07, 2018, 10:50:54 pm
content: Quote from: 2N3055 on September 07, 2018, 09:55:29 amDefinitely my thoughts. LeCroy's had good math and analysis functions for a long time, and a 2000s era scope with a good bit of bandwidth can be had without too much budget, though it's a lot larger than a modern one.The nice thing about the Picoscope is that since it's all on the computer anyways, there is very little limiting your analysis options, though you get the normal limitations of USB bandwidth and such.LeCroy memory options for that range of scopes is all hardware, consider also the DDA-125/200 series scopes which have large memory as a baseline. I'm not 100% on it, but I don't think I've heard of a LeCroy scope of that general vintage losing cal because of a battery, I think it's likely EEPROM or similar.

author: Mr Nutts
author_rank: Regular Contributor
timestamp: September 08, 2018, 07:27:00 am
content: Quote from: Hagrid on September 07, 2018, 11:30:06 amSure, fire ahead and I'll do what I can but I'm far from an expert for these scopes.BTW here's a spec sheet for the Waveruner LT scopes I have:https://www.testequipmenthq.com/datasheets/LECROY-LT374-Datasheet.pdfAnd here's a review of a LT264M by a former member:https://www.eevblog.com/forum/testgear/lecroy-waverunner-2-lt264m-review-and-(partial)-teardown/

author: Mr Nutts
author_rank: Regular Contributor
timestamp: September 08, 2018, 07:28:01 am
content: Quote from: Hagrid on September 07, 2018, 10:08:10 pmThe sample memory in the Waverunner LT and Wavepro 900 scopes is software-limited, i.e. the scopes come with hardware for max memory which is locked through software.The older scopes have proprietary memory modules as far as I know.QuoteNo. Cal data is stored in an EEPROM, if the backup battery (which are coin cells and not the dreadful Dallas modules) dies then the scope starts misbehaving, i.e refusing to boot or crashing a lot. Replacing the battery fixes it.I highly recommend you read the lecroy-related threads former member Wurstchenhund has posted in. He's some kind of guru when it comes to those scopes, and I learned a lot from them. He's been banned from this forum (don't ask me why, I don't know) but he's now active on the Allaboutcircuits forum. I contacted him and asked him many questions and he answered them all in detail and in a way even I could understand, lolEdit: sorry for the typos and chaotic posts, I'm on vacation and all I have is this shitty cell

author: JS
author_rank: Frequent Contributor
timestamp: September 08, 2018, 07:39:31 am
content: I seriously don't understand why user can't add apps to those devices, fridges come with that feature now days!That would solve a ton lot of issues, opening that would mean user can use the scope to whatever he wants and the manufacturer doesn't need to add fancy features, just the basics running on the asic and standard functions, then the user can add a post processing app to do whatever he likes. Would be a great selling point for whoever get's it, in a cheap scope would be a killer as sometimes you don't need fancy converters but you need specific post processing, as is your case.JS

author: Mechatrommer
author_rank: Super Contributor
timestamp: September 08, 2018, 10:28:30 am
content: Quote from: Fungus on September 07, 2018, 10:33:09 amimho Rigol DS1000Z Series is half a Picoscope and half a stand alone DSO with proper buttons. its just a matter of getting someone to do the programming on PC side to do anything that the users/he want. if you learn how to program, you can save tons of money, if not, company may charge you ferarri class DSO and services. Lecroy was the scope of the day, if a company redo that scope design today, the price will still not feasible to hobbiests, just as few model names mentioned in this thread (or even worst).