Cheap scopes, Siglent vs Rigol - Page 1
Forum section: electronics / testgear

author: Rmadd
author_rank: Newbie
timestamp: October 03, 2016, 04:59:32 pm
content: So I'm currently an EE student and I'm looking to start a small electronics lab to learn more about everything and maybe do a few projects. On the subject of O scopes, I want a relatively cheap one that doesn't completely suck so following Daves advice I was going to pull the trigger on a Rigol DS1054Z ($400 US). Then I noticed Siglent makes the 1052DL for $240... I did a few searches and nobody on here really talks about it, even though the amazon reviews are very positive. Baisically what I'm asking is has anyone had experience witht the Siglent and would you recommend it for a first time scope buyer, over the Rigol.

author: JPortici
author_rank: Super Contributor
timestamp: October 03, 2016, 05:26:52 pm
content: Quoteyeah, there are reasons for that.32k memory points for instanceNo serial decode is another1072CML+ is newer, with more memory, with more bandwidth for a sligtly higher price, but still no decode. if i had to buy a siglent i wouldn't get anything less than sds1000x seriesanyway, siglent makes better hardware than rigol, as much better as it can be when you are racing to the lowest cost

author: Rmadd
author_rank: Newbie
timestamp: October 03, 2016, 05:40:12 pm
content: Quote from: JPortici on October 03, 2016, 05:26:52 pmWould I grow out of the 1052 too quickly for it to be worth it?

author: JPortici
author_rank: Super Contributor
timestamp: October 03, 2016, 05:49:32 pm
content: in my opinion buying a new digital scope without serial decode options is a waste of money, especially if you don't have other tools

author: alsetalokin4017
author_rank: Super Contributor
timestamp: October 03, 2016, 05:57:08 pm
content: Quote from: Rmadd on October 03, 2016, 05:40:12 pmYes... the first time you need 3 or 4 channels.

author: Rmadd
author_rank: Newbie
timestamp: October 03, 2016, 06:03:27 pm
content: Quote from: JPortici on October 03, 2016, 05:49:32 pmWould that be listed under the logic analyzer on the scopes description?

author: nctnico
author_rank: Super Contributor
timestamp: October 03, 2016, 06:17:12 pm
content: Quote from: Rmadd on October 03, 2016, 06:03:27 pmNo, it is listed as protocol decoding which usually works for the analog channels. Decoding on digital channels isn't always supported. When it comes to the Rigol 1054Z: it is only worth buying if you are going to hack it. If not then there are much better deals out there.

author: Rmadd
author_rank: Newbie
timestamp: October 03, 2016, 06:24:16 pm
content: Quote from: nctnico on October 03, 2016, 06:17:12 pmIf I'm using an o scope for mainly educational purposes with some small projects on the side, is decoding something that I should look for? I'm very new to Oscilloscopes so I'm not entirely sure what I should be looking for and what is actually a good deal.

author: JPortici
author_rank: Super Contributor
timestamp: October 03, 2016, 06:29:22 pm
content: Rigol 1054z is fine for you, a good starter package. It has a bit of everythingBeing an EE student i bet you have only used tektronix TDS2000 or simiar, it will be slightly better (same slow speed but capable of more stuff)If you weren't on a strict budget i wouldn't recommend it thought. (I'd recomment a GWi 2104 but you are in another class of instrument.. and double the price)

author: Rmadd
author_rank: Newbie
timestamp: October 03, 2016, 06:31:44 pm
content: Quote from: JPortici on October 03, 2016, 06:29:22 pmYeah Id say I'm on a tight budget, as I need to get a lot of other stuff to have a good lab, I'm mainly going off of Daves video on how to set up a lab, although with a few exceptions.

author: nctnico
author_rank: Super Contributor
timestamp: October 03, 2016, 06:34:14 pm
content: Quote from: Rmadd on October 03, 2016, 06:24:16 pmIf you are going to work on projects with a microcontroller (which I assume you will) then protocol decoding is essential because sooner or later you will encouter a chip which communicates through I2C or SPI. Communication using a UART is also very common so being able to decode that is handy as well.

author: JPortici
author_rank: Super Contributor
timestamp: October 03, 2016, 06:36:29 pm
content: Cheap scopes are always a compromize between functions, speed, memory and of course analog performance.What do you need?you know. Do you want to do digital stuff, communication like spi/i2c? You can decode on paper but that slows you down a lot.You know that at some point you'll want to mess with stuff like CAN bus? Then you have to consider that.Or, if you never have to look at >30Vsignals you can also consider a usb based scope, but nothing less than a picoscope. You'll lose all the physical controls but because you don't have to pay for those you can get a very powerful instrument for a fraction of the cost. It also support pretty much ANY commercial serial standard with no limitations in thresholds, baud rates and such. Guess what i keep on the pc area at work, or when i have to look inside car busses and such..a 100-200€ picoscope where the next alternative would be a keysight or lecroy which starts at 3k€ plus the needed options.

author: Rmadd
author_rank: Newbie
timestamp: October 03, 2016, 06:43:21 pm
content: Quote from: JPortici on October 03, 2016, 06:36:29 pmIm definitely going to be doing digital stuff with micro controllers, and Im also going to be helping with a digital communications project soon. The Rigol 1054z has UART and I2C, how likely would I be to encounter a need for other types?

author: JPortici
author_rank: Super Contributor
timestamp: October 03, 2016, 06:48:03 pm
content: Spi is critical. But the 1054 has it too.The next would probably be canbus, but i never really needed it until a couple of weeks ago and you won't until you mess with cars and shit (at uni stuff like formula SAE, but the mean seniors will keep all the fun parts for themselves)

author: Fungus
author_rank: Super Contributor
timestamp: October 03, 2016, 06:59:53 pm
content: Quote from: Rmadd on October 03, 2016, 06:43:21 pmIt also has SPI.Between those three protocols you pretty much have it covered.Youcouldbuy the Siglent plus a cheap logic analyzer, but... the Rigol is a much better 'scope. In the long term you won't regret spending the extra money on a DS1054Z.You'll almost certainly regret buying the Siglent (eg. the day you need more than 2 channels).

author: rstofer
author_rank: Super Contributor
timestamp: October 03, 2016, 07:06:40 pm
content: Quote from: JPortici on October 03, 2016, 06:48:03 pmI might consider a logic analyzer if I were to encounter the CAN bus. So far, I haven't.I bought the DS1054Z specifically for the decoding. On SPI it is terrific. You need 4 channels for SPI so don't even bother looking at 2 channel scopes. Yes, you can cobble your way around the requirement with a 2 channel scope and external trigger (trigger off CS') but you only see one side of the transaction (assuming you want to see the clock edges, and you do).If you buy the DS1054Z you will absolutely want to unlock the options (bandwidth, memory depth and decoding). The process is well understood. Search the forum for DSER.If you don't have $400, consider the Digilent Analog Discovery at $279. It's only two channels on the scope (limited to 25V) but it has a bunch of other features like a dual signal generator and 16 bits of digital IO including a logic analyzer function. Discussion elsewhere, search the forum.Try this with a scope:https://www.eevblog.com/forum/beginners/playing-with-the-analog-discovery/

author: tautech
author_rank: Super Contributor
timestamp: October 03, 2016, 07:32:22 pm
content: Quote from: rstofer on October 03, 2016, 07:06:40 pmNot entirely correct if you're just decoding.The SDS1102X are under promotion, 100 MHz, true 500uV/ div range and decoding suite with CAN and all at double the waveform update rate of a 1054Z.http://www.siglentamerica.com/pdxx.aspx?id=4688&T=2&tid=1Thread:https://www.eevblog.com/forum/testgear/siglent-sds1000x-series-oscilloscopes/

author: JPortici
author_rank: Super Contributor
timestamp: October 03, 2016, 07:48:23 pm
content: Quote from: rstofer on October 03, 2016, 07:06:40 pmhmm..maybe if you have to look at others' working hardware? but even in that case..if i am working on a car i haven't encountered yet and i have to have an idea of what the messages on the bus on the obd port means there are dedicated tools that group data, plot diagrams and such. but if you don't have those yes, a with a logic analyze you could record a shitton of data and do the hard work by hand (being doing that at the moment)if however i have to develop hardware (and i haven't had to do that yet, others with more experience in this field please correct me) looking at the analog signal is more important, eye diagrams and such.

author: Fungus
author_rank: Super Contributor
timestamp: October 03, 2016, 07:55:01 pm
content: Quote from: tautech on October 03, 2016, 07:32:22 pmHah! They've put Dave's EEVBLOG review video on their product page!I wonder if Siglent watched it all the way to the end?(ie. To where Dave tells you whether to choose Rigol or Siglent... )

author: nctnico
author_rank: Super Contributor
timestamp: October 03, 2016, 08:05:46 pm
content: Quote from: Fungus on October 03, 2016, 07:55:01 pmI don't think they watched or understood it because Dave says clearly he recommends a hacked 1054Z over the SDS1000X seriesQuote from: JPortici on October 03, 2016, 07:48:23 pmA logic analyser is a very poor tool for protocol decoding because in many cases problems originate from the analog domain so using analog channels to hunt for a problem is mandatory. BTW: when it comes to looking at large amounts of CAN messages you are way better off using a CAN adapter (like the Lawicell CANUSB) and software (like CAN monitor pro from WG soft).

author: rstofer
author_rank: Super Contributor
timestamp: October 03, 2016, 08:22:48 pm
content: I guess if I were working on the CAN bus it would be between 2 of MY controllers as I have no interest in automotive applications. Given that scenario, I can come up with a lot of ways to troubleshoot the bus and that CANUSB is a pretty good one. A logic analyzer might work and I might even be able to use a scope for short packets. Lots of ways...Just like we dealt with serial buses long before DSOs came along. Somehow, despite our crude instruments, we got things built.

author: Rmadd
author_rank: Newbie
timestamp: October 03, 2016, 08:33:52 pm
content: Thanks everyone for all the help! I think the Siglent is out of the picture now, I didn't realize how poor the memory was on it and I now understand the need for decoding.

author: tautech
author_rank: Super Contributor
timestamp: October 03, 2016, 08:42:28 pm
content: Quote from: Rmadd on October 03, 2016, 08:33:52 pmYep, a SDS1052DL is the bottom of the barrel these days however 20 years ago that amount of memory was considered sufficient.A good graphic of why memory depth is important can be seen in this post by rf-loop:https://www.eevblog.com/forum/testgear/siglent-sds1000x-series-oscilloscopes/msg933997/#msg933997

author: Fungus
author_rank: Super Contributor
timestamp: October 04, 2016, 01:22:02 am
content: Quote from: nctnico on October 03, 2016, 08:05:46 pmYep, and on their own product page! You couldn't write comedy like this if you tried...

author: tautech
author_rank: Super Contributor
timestamp: October 04, 2016, 06:45:41 am
content: Quote from: Fungus on October 04, 2016, 01:22:02 amSo you like comedy ?This is comedy:https://www.eevblog.com/forum/projects/project-yaigol-fixing-rigol-scope-design-problems/

author: Fungus
author_rank: Super Contributor
timestamp: October 04, 2016, 09:09:42 am
content: Quote from: tautech on October 04, 2016, 06:45:41 amMaybe it's just me but I found the writing style very poor, the acting was wooden and the plot was full of holes. I think most people will leave that thread disappointed and wanting their time back.A valiant effort, but only 2/10.

author: JPortici
author_rank: Super Contributor
timestamp: October 04, 2016, 10:28:06 am
content: but seriously, please stop the pissing contestQuote from: rstofer on October 03, 2016, 08:22:48 pmof coursewhen i started educating myself on the protocol i used to take the acquisition screenshot of the packets and went on decoding by hand, comparing the reuslt with the analyzer

author: Fungus
author_rank: Super Contributor
timestamp: October 04, 2016, 10:44:44 am
content: Quote from: JPortici on October 04, 2016, 10:28:06 amWasn't me. I just thought it was hilarious that Siglent put a video on their website telling people to buy Rigols.Some people around here just seem to take offense when anybody mentions the DS1054Z inanycontext. At the end of the day it's a $400 oscilloscope with a ton of features. Of course it's not the best oscilloscope ever in history but it's very complete, has 4 channels, and what's not to like at that price?