Buying 1st DSO. Need advice on what specs meet my reqs! - Page 1
Forum section: electronics / testgear

author: chinglish
author_rank: Contributor
timestamp: August 08, 2013, 01:41:38 pm
content: Hey guys,I'm new to the eevblog forum, the typical 'long time reader, first time poster'. I live in Germany, been involved in 'electronics design' since i was about 6. Well, as you might have guessed from the quotes, these have been fairly crude circuits - very basic stuff, mostly simple repairs.For a future project (but not limited to), I need a decent oscilloscope. I won't go into much detail, but basically I want to analyse serial data connections (no fancy stuff), just very basic debugging/reverse engineering. It's kind of a learning-by-doing thing, nothing critical.There will be lots of other other uses for it in the near future ofc, but I yet have to determine what these uses will be, so a good 'allrounder' is needed. Because I have very limited experience with oscilloscopes in general, and even less with DSOs, I don't want to spent a lot of money.I did some research ofc, watched a lot of reviews, etc. and..these are the scopes im particular interested in:- Siglent SDS1102CML (360 Eur)- Owon SDS7102 (330 Eur)I know the Owon has some fairly major flaws (UI, noise, refresh rate), but the memory depth seems unrivaled (in that price range). What I don't is.... Do I need so much memory? Is the refresh rate important for my project? I really love the big screen and especially the small footprint. The optional battery sounds very interesting, too.Overall, the Siglent seems to be a more solid choice, with better UI, better build quality. But it lacks the portability/huge memory, has a smaller screen and costs even a bit more.What do you guys think? Any (other) suggestions?PS: 350 Eur = 467 USD = 301 GBP = 514 AUDPPS: Oh yea, what I'm mostly interested in (and thus planning on using the scope for): Audio equipment, PSU design, micro controllers, data connection analysis, led lighting.

author: dfmischler
author_rank: Frequent Contributor
timestamp: August 08, 2013, 02:09:18 pm
content: How fast a data link do you want to be able to see? Any standards applicable (ethernet, usb, i2c, spi, etc)? How fast a clock on the uC?

author: chinglish
author_rank: Contributor
timestamp: August 08, 2013, 02:29:23 pm
content: Quote125 to 500 kbit/s max. It's a CAN-Bus. Various other proprietary stuff, too... Don't know the specs, that what i need that scope for. Nothing super-fast... simple stuff.QuoteDon't know yet. Didn't bother playing around with these things, mainly because of lacking equipment.

author: echen1024
author_rank: Super Contributor
timestamp: August 08, 2013, 03:29:06 pm
content: Quote from: chinglish on August 08, 2013, 02:29:23 pmThe Siglent SDS1102CNL is slightly cheaper, if you don't need the long memory, or just go ahead and et everyone's favorite budget scope, the Rigol DS1052E.

author: casper.bang
author_rank: Frequent Contributor
timestamp: August 08, 2013, 03:34:57 pm
content: I'm in the same boat as you, can't decide what to get in this price range.+ for Siglent:There seems to be more firmware updates for Siglent than Owon. 2Mpts is still a decent amount of capture memory compared to a lot of other budget scopes. Last but not least, Dave did not give the Owon a lot of love when he had it in for a review!+ for Owon:Larger memory and battery option (no mains ripple)My gut feeling tells me that the SDS1102CML is the safer choice, Siglent is a large OEM and the scope reminds a lot of the popular entry level Rigol DS1052E (which I've played with over a few days) but with larger screen, better UI and double the memory. The DS1052E was so noisy, with too small a screen and no single shot button that it won't be a candidate for me.

author: Unknown
author_rank: Unknown
timestamp: August 08, 2013, 04:25:47 pm
content: For slow serial protocols a basic 8 channel USB logic analyzer like theSaleae Logicmight be a better tool than a scope, since they support decoding for common serial protocols, unlike the cheap scopes. You would need an external transceiver for CAN, though.

author: chinglish
author_rank: Contributor
timestamp: August 08, 2013, 06:55:41 pm
content: Thanks for your help!QuoteI think the CNL is no real alternative for me. If I can get more memory (that may come in handy) and it's within my budget.. why go for the lower cost one? The difference is just too low to justify it.Regarding the Rigol: I share casper's opinion on that. It may be a solid choice, but it's missing some nice features, such as the big screen. That may not matter to some of you, but to me, it's rather important.QuoteYep. But then again... maybe the Owon is worth a try, even though it got rather mixed reviews. I really like the portability. Especially when it comes to automotive projects, like that CAN-Bus thing im planning, the battery option may pay out.QuoteYes, you're right. In fact, I already own some hard-/software for CAN analysis. But when it comes to debugging/testing 'in the field', you really can't do much with it + I need to carry around my big old laptop for that. Thing is, I don't just want to look at the data. I want to build something that will talk to those CAN devices. And I need something to analyse the waveforms and spot errors in the whole circuit, not just read/generate data. As stated before, I'm planning on using the scope in plenty of future projects, not just this one.I think my problem is, that I don't really understand those memory numbers. Well, I can tell the Owon got a lot of it (and what those numbers mean), but I can't tell what I can use this for. When is it needed? Would be really great if someone could elaborate this for me, considering the type of applications I have in mind (audio, data connections, circuit design).

author: echen1024
author_rank: Super Contributor
timestamp: August 08, 2013, 07:12:25 pm
content: Quote from: chinglish on August 08, 2013, 06:55:41 pmAlso, you might want to look at the Rigol DS1074Z on tequipment.net. It's 4 channel/70meg, with a 7 inch 800x480 screen, and additional features such as function gen, I2c/SPI/CAN/LIN serial trigger, maybe decode. It also comes with 12Mpts mem standard, with upgrade to 24.

author: chinglish
author_rank: Contributor
timestamp: August 08, 2013, 07:19:36 pm
content: QuoteThatreallylooks promising. I never heard of this model before! Seems a bit more expensive, but maybe worth it... Will look into it, tyvm!QuoteDidn't know Dave had it in for a review. Got a link for me?EDIT: nvm, found it! If someone is interested:http://www.yourepeat.com/watch/?v=RmJ2pZloW18

author: Chalky
author_rank: Regular Contributor
timestamp: August 08, 2013, 07:53:19 pm
content: It's a shame that used Fluke 125 portable scopemeters are so hideously overpriced.

author: casper.bang
author_rank: Frequent Contributor
timestamp: August 08, 2013, 07:57:24 pm
content: The Rigol DS1074Z looks interesting but it confuses me a bit too. Best I can tell, it looks like a bit less professional (lower wave capture rate, smaller extension option) but with some more value features (extra channels, function gen.) than the DS2072 series. I guess I wish Rigol would release a DS1072 for $100 less, because even though $600 looks good, after VAT and shipping, might as well have ordered a DS2072 locally. I hope and pray (not really) that Rigol have realized, with their DS1052E, that there's a large hobby segment to be had with a DS1072.

author: chinglish
author_rank: Contributor
timestamp: August 08, 2013, 08:26:10 pm
content: QuoteAbsolutely. I might as well sit back and PM you in a few weeks...Also... After watching Dave's review... well, the Owon seems just awful, even to a noob like me. Next please...So basically it boiled down to that Siglent. The Rigol Z is a bit too expensive (for me), plus, no local retailer here in Germany. The only other option (i know of) would be some Hantek. There seem to be a lot of resources/hacks for this thing, but it got some pretty bad reviews.Will look into it further and report back.Oh, and still need info on that topic:Quote

author: echen1024
author_rank: Super Contributor
timestamp: August 08, 2013, 08:29:53 pm
content: Quote from: casper.bang on August 08, 2013, 07:57:24 pmThe 1074Z is the first compelling low-end 4 channel scope I have seen. Very cheap(for 4 channel), and quite good features. Rigol's own CA(?) series looks quite bad imo.

author: casper.bang
author_rank: Frequent Contributor
timestamp: August 08, 2013, 08:34:20 pm
content: QuoteDave actually dived into this as well, in his video about DSO's:http://www.eevblog.com/2009/06/17/eevblog-13-part-1-of-2-digital-storage-oscilloscope-tutorial/I like to think of it as a DSLR sensor, where a larger one allows you to zoom more in and pan around from a cropped section. 1Mb on the Rigol 1000 series I tried, give just enough of a "window" at 1200 baud for me to see about 3 full bytes. I imagine the Rigol 2000 with 12 times as much, would potentially allow me to see 36 bytes?!

author: chinglish
author_rank: Contributor
timestamp: August 08, 2013, 09:11:33 pm
content: QuoteWell, I get the basic concept. I've been working in the (audio) entertainment industry, and sample rates and all that stuff is very well known to me. But it's quite hard to imagine a number of.. say 10M in a more practical way if you've never really used a DSO. Your numbers are quite helpful though, thanks!QuoteThat's what I thought. But sadly, even though it's pretty cheap considering it's features, it is still a bit too much for me. I'm on a tight budget, I never used a DSO to design/analyse stuff, I might even break it because I made some dumb mistakes. Who knows? Would be really painful to wreck a 600+ USD scope. And when it fails because of faulty electronics, theres no local retailer. I'd have to send it from Germany to the USA. Would take weeks till I get a new one, or mine repaired.EDIT: If I want to analyse some (irregular) serial data, like from a CAN-Bus, are there any must-have features for that? Don't need a decoder... I'm thinking more of things like special memory functions or trigger modes.

author: echen1024
author_rank: Super Contributor
timestamp: August 08, 2013, 09:23:33 pm
content: Quote from: chinglish on August 08, 2013, 09:11:33 pm

author: jav
author_rank: Contributor
timestamp: August 08, 2013, 09:47:24 pm
content: Quote from: chinglish on August 08, 2013, 08:26:10 pmHas you askedBatronixif they sell that model? It isn't on their website, but from my experience they're very responsive.

author: chinglish
author_rank: Contributor
timestamp: August 08, 2013, 10:38:33 pm
content: QuoteNope, thanks for the tip. I will look into that.QuoteI read that; but my understanding is, that I only need a single-shot trigger to capture the frame and enough memory to display the full length of the frame. Correct?

author: echen1024
author_rank: Super Contributor
timestamp: August 09, 2013, 12:12:11 am
content: Quote from: chinglish on August 08, 2013, 10:38:33 pmExactly. I've had to manually decode various data transmissions. It's time consuming, but it works nonetheless. Oscilloscopes are complex beasts, even though I've never blown one up, one of my friends has.