the eternal question about rigol vs siglent - Page 1
Forum section: electronics / testgear

author: Gregi
author_rank: Contributor
timestamp: March 21, 2019, 12:37:48 pm
content: First of all sorry for my english....I am a begginer in electronics. I mostly play arround with arduino,linear power supplies, audio amplifiers and everything else i can destroy. Now I am in a scope dilema. I want a scope. I am watching Rigol DS1054Z and Siglent SDS1104X-E. First of all I have no idea how to use a digital scope (I had an old analog hameg before). I dont care about the 100 € price difference between the two. So my question is which one to buy, or even better which one of them would you call a scope for dummiesIve red a zilion pages here on forum but i havent found even one straight answer like buy rigol because of this or buy siglent because of that...I will order from batronix probably.https://www.batronix.com/shop/rigol/DS1000Z.htmlhttps://www.batronix.com/shop/oscilloscopes/Siglent-SDS1104X-E.html

author: nctnico
author_rank: Super Contributor
timestamp: March 21, 2019, 12:46:09 pm
content: Get the GW Instek GDS1054B and hack it using the simple license key generator from this forum. It costs about the same as the DS1054Z and it can do much more.

author: tautech
author_rank: Super Contributor
timestamp: March 21, 2019, 01:02:32 pm
content: EEVblog isn't the only place that has healthy discussion on scopes.If you haven't been here this thread is probably worth a read:https://forum.allaboutcircuits.com/threads/best-oscilloscope-right-now-under-500.156985/Some past and present very knowledgeable EEVblog members are part of this ^ discussion.You'll be fine with a DSO as that CRO experience will stand you in good stead and then all you have to master are the features a DSO offers.

author: Old Printer
author_rank: Frequent Contributor
timestamp: March 21, 2019, 01:07:48 pm
content: If cost is not a concern I would go with the Siglent, as soon as stock is in at Saelig that’s what I am doing. The differences have been well documented here but if you are a noob like me you won’t understand all of them anyway. It has 2 ADCs and twice the sampling rate for starters. You really should keep reading here until you get a better handle on what you are buying.

author: 2N3055
author_rank: Super Contributor
timestamp: March 21, 2019, 01:31:16 pm
content: Rigol DS1000Z is nice, good quality BASIC scope. It is not very fast, FFT is not very good (still somehow usable) decoding is very basic but also usable for occasional packet here and there. Where it is very good is analog like display of waveforms, quite deep memory and generally good quality. Also it is not very new, and pretty much no bugs in what people are using most of the time.That being said, Siglent 1000X-E series (4ch) has dual A/D converters, more sample memory, segmented mode, measurements on full memory, long FFT etc etc.It also has lower noise frontend with real 500uV/div range.It is a better scope. It is also much newer (hence better specs) but because of that, occasional bug is still found here and there, although basic stuff is sorted out and no major problems..Mentioned GW-INSTEK is also nice little scope, but little bit more expensive than both. It is between the two mentioned ones in specs, and is also nice and stable.There are also MICSIG tablet scopes, very good for the price and portable and battery operated. If you go out in the field or go to workshops and collaborate with other people, that one is great...Any one of them will be HUUUGE upgrade from having no scope...

author: tv84
author_rank: Super Contributor
timestamp: March 21, 2019, 02:04:31 pm
content: Quote from: Gregi on March 21, 2019, 12:37:48 pmIf after the zillion you haven't found that, it can only be because you read the wrong zillion pages!

author: Fungus
author_rank: Super Contributor
timestamp: March 21, 2019, 02:52:44 pm
content: Quote from: Gregi on March 21, 2019, 12:37:48 pmYou'd better buy the more expensive one then. You'll suffer from "I'm sure the grassmighthave been greener" syndrome if you don't.Quote from: Gregi on March 21, 2019, 12:37:48 pmIf you've never owned a 'scope before then either will blow you away.The capabilities of both are really very similar, the bang-per buck ratio is very similar, don't expect to decide based on either of those.eg. "Bandwidth". A hacked DS1054Z has close to 200Mhz bandwidth (measured). The Siglent has more, yes, but once you get to these levels then probing technique and a dozen other factors are more important than raw bandwidth for getting good results. I wouldn't decide between the two based on "bandwidth".The real difference is in the way they work, eg. I like the row of buttons down the left side of the Rigol for selecting on-screen measurements. The Siglent has to go through a whole series of popup windows and knob twiddles to turn on a measurement, it's a single button-press on a Rigol. Other people will fixate on other things.ie. At the end of the day which works best for you will come down to what will be your most common daily tasks. Onlyyouknow that (or maybe not) so nobody can really decide for you.If in doubt, toss a coin.(...or go with the cheaper one so you've wasted less money when you decide to get a Rigol MSO5000 instead)

author: Fungus
author_rank: Super Contributor
timestamp: March 21, 2019, 03:16:27 pm
content: Short version: If the question is "eternal" then there's no correct answer.ie. You're on your own.

author: nctnico
author_rank: Super Contributor
timestamp: March 21, 2019, 06:26:58 pm
content: IMHO the Rigol DS1054Z is pretty much outdated. It is cheap but it has several large drawbacks. Look at Dave's recent DIY EMC probe FFT comparison video for example.

author: Fungus
author_rank: Super Contributor
timestamp: March 21, 2019, 09:19:10 pm
content: Quote from: nctnico on March 21, 2019, 06:26:58 pmSure, but who needs FFT? Not me.(and it's not as if the Siglent has an amazing FFT either)

author: nctnico
author_rank: Super Contributor
timestamp: March 21, 2019, 09:24:52 pm
content: FFT is just one thing. Low samplerate with all channels on is another. The newer scopes have more CPU power under the hood and therefore can do more sophisticated things like math, full memory decoding, etc. The DS1054Z just isn't a good buy because it is an outdated design.

author: Fungus
author_rank: Super Contributor
timestamp: March 21, 2019, 09:48:50 pm
content: Bang/buck ratio is about the same IMHO. The Siglent costs forty-odd percent more and is approx. forty-odd percent more powerful.If you have the money then get the Siglent but the Rigol is still more than enough oscilloscope for most hobbyists. It displays four wiggly lines on screen just fine.

author: drescherjm
author_rank: Contributor
timestamp: March 21, 2019, 09:53:59 pm
content: This week I just put the SDS1202X-E in my wishlist so I am very interested in the discussion about this since I have a similar need as the OP.

author: Hydrawerk
author_rank: Super Contributor
timestamp: March 21, 2019, 10:26:33 pm
content: Quote from: nctnico on March 21, 2019, 12:46:09 pmReally? Can GW Instek GDS1054B do serial decoding?

author: MarkF
author_rank: Super Contributor
timestamp: March 21, 2019, 10:39:59 pm
content: Most of the Siglent 1104X-E looks pretty good except that the measurements window is transparent and very hard to read (See video starting 13:30).I bought the Rigol DS1074Z several years ago before the 50MHz model was available. I've been satisfied but it has it's quarks too.

author: nctnico
author_rank: Super Contributor
timestamp: March 21, 2019, 11:12:26 pm
content: Quote from: Hydrawerk on March 21, 2019, 10:26:33 pmWhen hacked: yes. Just read the thread. 200MHz bandwidth is also possible but probably only with 2 channels active. The price is about equal to the Rigol 1054Z so buying the GDS1054B instead is a no-brainer.

author: rhb
author_rank: Super Contributor
timestamp: March 21, 2019, 11:24:28 pm
content: What's important to you?The Owon XDS2102A is only two channels, but it will give you 12 bits of ADC resolution for $400 US. It will dump 20 MPts to USB reasonably quickly in a fairly simple format. The UI is horrible, but as a DAQ it's usable. If you're really good at DSP with MATLAB it's an excellent choice. I will be writing a Unix command line program to do vector network analysis with 100 dB dynamic range using the Owon as well as 8 bit DSOs. I have an HP 8753B VNA, so I'll be able to make apples to apples comparisons.In general, the Instek GDS-2000E line is probably the best. You can easily hack a 207x to 200 MHz and enable a pretty decent SA interface which is officially only available on the MDO versions. It's quite a bit more $$ But GW have been very good in my experience with bug fixes.I have made extensive use of the Instek SA app for EMI work. Downside of the Instek is it generates a *lot* of EMI from the SMPS. There is *no* shielding. That said it is my primary scope.My Rigol DS1102E has the best UI of the 3. My experience with a Siglent SSA 3021X SA was not very reassuring. I've not played with an SDS1000X-E system yet.The truly sad part is that if you buy an MSOX3000T from Keysight or an RTM3000 from R&S for up to $20K you will simply get a different collection of problems. I was absolutely stunned at how poor both of those are. And damn glad I could return the MSOX3104T I bought for $10K.Which is why I am reading "VLSI DSP Systems" by Parhi so I can write sensible FOSS FW for Zynq and Cyclone V based DSOs. So when I start actually coding FW I'll buy a Siglent for testing. And fix or replace my GDS-2072E.If I were severely cash constrained, I'd buy a Rigol DS1054Z because it has a better UI. The Instek is almost twice as much, but is also much more capable. Until I fried it, the hacked GDS-2072E produced the same results from a 40 ps rise time square wave generator from Leo Bodnar as the MSO-2204EA.If dynamic range mattered, I'd get an Owon despite everything else about it being crappy. About the Siglent I can't say as I haven't tried one yet. Even if you have the money, I would not recommend either the MSOX3000T or the RTM3000. The RTM3K has a wonderful UI. It will be a great DSO when the FW is finished. But at the moment it's a very expensive beta version test instrument.

author: HalFET
author_rank: Frequent Contributor
timestamp: March 21, 2019, 11:58:33 pm
content: May I give a totally different piece of advice: try to get some time on both and check which one you like the most in terms of interface. In terms of raw performance both Siglent and Rigol will be roughly similar for most applications.

author: DaJMasta
author_rank: Super Contributor
timestamp: March 22, 2019, 12:09:11 am
content: Quote from: HalFET on March 21, 2019, 11:58:33 pmNot exactly, the Siglent has an edge because it's part of a much newer product refresh. The Rigol has the benefit of the really easy unlocks (though the Siglent unlocks too, right?), but the Siglent is modestly more capable and is more responsive to use. I'd go as far as to say if the cost difference is of no concern, the Siglent 1104X-E is definitely better than the Rigol DS1054Z. If you're looking for bang per buck, maybe the Rigol has an edge unlocked, but its hardware is much older, so I'm not even sure it qualifies for that, maybe for some applications. Personal preference for menus and such could swing it either way, I do think they're close, but given the OP's constraints and concerns, I would go with the Siglent or consider a different option if one's apparent (honestly, I just don't know many of the other entry level scopes, and Rigol/Siglent generally have the most polished UIs.) Hopefully Rigol can refresh it soon!

author: HalFET
author_rank: Frequent Contributor
timestamp: March 22, 2019, 01:09:23 am
content: Quote from: DaJMasta on March 22, 2019, 12:09:11 amHow many times do you use these optional features? Not sure about you, but the decoder I stopped using years ago, it's quicker to just look at the waveform with the Mark 1 Eyeball for I²C and SPI. And the built-in waveform generators and multimeter options are usually a sorry excuse for a real instrument which you can pick-up of ebay for less than the license cost for one of these modules. Sure, some things like decoding for more complicated busses (i.e. USB) or advanced trigger options are nice, but given that he's asking for help choosing here I'm going to guess he's not quite at the stage where he's facedesking over how horrible of a protocol USB is.Which is to say, I'd look at functionality for that specific person instead of citing stats and looking at the age difference, neither of these scopes will age beyond the first two years of being a serious electronics hobbyist. Just the combination of the channel Y settings into a single panel group for all channels is enough to annoy most folks out of a scope if they have other options available.

author: tautech
author_rank: Super Contributor
timestamp: March 22, 2019, 02:42:22 am
content: Quote from: HalFET on March 22, 2019, 01:09:23 amWhich optional features ?For the X-E they are:16ch MSOWiFiAWG plus external HW box.QuoteNot all are as experienced as you, consider yourself lucky.QuoteFor most an AWG is not a necessary option but to have one as part of an instrument can save space and yes standalone AWG's inevitably offer better output drive and more features.However the X-E's ability to do FRA/Bode plots with the optional AWG, another Siglent AWG or with some little trouble another brand AWG, is a distinct advantage for the novice with limited $ and experience to characterize their own filters and pass band filters with a modest additional outlay.QuoteSo you are blind to the many on this forum using 30+ year old equipment for serious hobbyist use and some for professional use ?It might appear you have never used a cheap and good DSO.QuoteWell yes, once I would've agreed with you but when asked to beta test SDS1104X-E and previously only used scopes with dedicated individual channel attenuators I dreaded the thought of using a shared control.With my DSO experience, in that much of what you want to do is parked within menus behind buttons, the adaption to shared vertical controls was far easier than I first envisaged.

author: Fungus
author_rank: Super Contributor
timestamp: March 22, 2019, 05:31:54 am
content: Quote from: Hydrawerk on March 21, 2019, 10:26:33 pmThe Instek can do all sorts of things thanks to recent unlocks and an architecture based on plugins. If you're a hacker then it's really programmable.

author: bitseeker
author_rank: Super Contributor
timestamp: March 22, 2019, 06:47:58 am
content: Quote from: Gregi on March 21, 2019, 12:37:48 pmIn the current entry-level scope market, unless you have specific requirements that will point you to one model over another (which you don't seem to), your budget pretty much makes the decision for you.Since you don't care about the price difference between the Rigol DS1054Z and the Siglent SDS1104X-E, get the Siglent. If you couldn't afford the Siglent or didn't want to spend that much, then get the Rigol.QuoteBzzzt! Wrong answer. Either you haven't actually read anything or you haven't yet understood what you've read. This "what scope should I buy" topic has been covered at least every week for as long as I've been a member and each thread is full of answers of why you should buy X because of this or buy Y because of that. It's OK if you don't understand the answers, but they are literally everywhere.

author: Fungus
author_rank: Super Contributor
timestamp: March 22, 2019, 09:25:04 am
content: Quote from: bitseeker on March 22, 2019, 06:47:58 amThere's no clear statement of "XXXX is best, buy that!", which I guess he/she/it was looking for.(and the explanation is thatneitheris much better bang/buck ratio, it all comes down to budget)

author: SWR
author_rank: Regular Contributor
timestamp: March 22, 2019, 10:11:52 am
content: This is also my experience:Quote from: rhb on March 21, 2019, 11:24:28 pmBut as RHB writes: do you have the extra money and what are your needs?The MDO-2204EX gave me the best value for money, but this is a very subjective topic.I also have a Rigol 1052 modified to 100MHz analog bandwidth.It's fine for the price, but it's not even close to the GWI in usefulness for my subjective requirements ... It was cheap though - I'll give it that.Serial bus decoding was mentioned specifically earlier in this thread. The GWI will do UART/SPI/I2C/CAN/LIN bus and it has a very nice search feature including wild cards in case you don't want to flip through 29000 messages manually. Nctnico did a very good in depth review of it elsewhere in this forum.

author: HalFET
author_rank: Frequent Contributor
timestamp: March 22, 2019, 11:31:19 am
content: Quote from: tautech on March 22, 2019, 02:42:22 amThe logic analyser is nice to have, IF they include the connector (which they usually don't). I end up using the ones from my HP 1652B on my scope, but knowing the price of buying these cables and probes separately, you're better off buying the LA on its own. Don't quite see the point of the WiFi, always end up resorting to GPIB because it actually works.The AWG is of poor quality on most of these, I see it like the transistor tester they include in those cheap multimeters: sounds nice, limited use.Quote from: tautech on March 22, 2019, 02:42:22 amYes, and it doesn't take much time to learn it, additionally it allows you to spot actual issues that the decoders will fail to see. Reliance on automation makes for a bad engineer.Quote from: tautech on March 22, 2019, 02:42:22 amThe bode plot can be of some use if you do a lot of analog work, but the error on them is quite bad.Quote from: tautech on March 22, 2019, 02:42:22 amWhat the hell are you going on about? I didn't say he needed the newest and best equipment, in fact I'm arguing against that. A few years ain't going to make the difference. My favourite scope is a 20 year old HPAK I picked up second-hand for the price of one of these newer scopes. But I'm simply being realistic about the quality and capabilities of these scopes, they're not very usable if you're doing serious circuit design. There's a reason why you'll find very few rigol scopes in a professional or academic environment: you don't want to be fighting your equipment.Quote from: tautech on March 22, 2019, 02:42:22 amI started out with a GW Instek from yesteryear. If you want to know why I'm so adamant about UI you might want to use one of those, they're horrible. Sure they had fancy features such as component testing built in (sounds familiar doesn't it), but were entirely useless because you spent half the day bashing your head into the wall because of how cluttered the control panel was.Quote from: tautech on March 22, 2019, 02:42:22 amGetting things for free always makes them a lot more attractive.

author: nctnico
author_rank: Super Contributor
timestamp: March 22, 2019, 11:35:41 am
content: Quote from: HalFET on March 22, 2019, 01:09:23 amI agree about the multi-meter and internal generators. On many oscilloscopes you can't even trigger on the internal generatorBut I don't see how decoding is useless. I'm using decoding quite often on various DSOs (albeit not the really cheap low-end ones) and it saves me a ton of time trying to figure out how and where things go wrong when writing firmware.

author: drescherjm
author_rank: Contributor
timestamp: March 22, 2019, 12:11:19 pm
content: Quote from: Fungus on March 22, 2019, 09:25:04 amI can tell you this was what I was looking for with the thread. A clear buy XXXX over YYYY because of features Z1 .. Z5 are a bargain for the extra $40. Or even don't buy XXXX because it is unreliable.

author: Fungus
author_rank: Super Contributor
timestamp: March 22, 2019, 12:39:05 pm
content: Quote from: drescherjm on March 22, 2019, 12:11:19 pmSorry.For the difference in price you can buy the Rigol+something else (decent soldering iron, Brymen multimeter....) and for most people the difference in the Siglent will be small (eg. if you don't do FFTs all day long)

author: tautech
author_rank: Super Contributor
timestamp: March 22, 2019, 07:34:00 pm
content: Quote from: HalFET on March 22, 2019, 11:31:19 amThat's not what I found when doing a simple Bode plot exercise.You can see it written up in detail here:https://www.eevblog.com/forum/testgear/siglent-sds1204x-e-released-for-domestic-markets-in-china/msg1435854/#msg1435854And further when using a second Bode plot trace:https://www.eevblog.com/forum/testgear/siglent-sds1204x-e-released-for-domestic-markets-in-china/msg1436912/#msg1436912Quote from: tautech on March 22, 2019, 02:42:22 amGetting things for free always makes them a lot more attractive.Well you might think so but I have any # of DSO to use if I wish, however when accepting the chance to beta SDS1104X-E in 2017 I committed to having to use it and get used to it like it was my only DSO.I stand firmly behind the highlighted comments I made earlier. ^^^^As for the eternal R vs S question, if we can readandunderstand specification documents, features of one vs another become quite clear.A comparison chart compiled by member rf-loop outlines the major differences:

author: Fungus
author_rank: Super Contributor
timestamp: March 22, 2019, 07:45:04 pm
content: Oh, not that stupid chart again.Cherry picked data points? Check.Unhacked Rigol, no options unlocked? Check. (nb. Alloptions are now standard since that was written)Posted by a Siglent distributor? Check.Real value: 0

author: tkamiya
author_rank: Super Contributor
timestamp: March 22, 2019, 07:48:53 pm
content: I have more than dozen scopes. Tektronics, HP, Siglent, Rigol, Owon, etc, etc, etc. Owon which is a PC scope is a toy. But all the rest are remarkably similar.95% of things I do can be done with any of them, so I just use whatever is conveniently situated. Last 5% gets tricky. Maybe some of mine can do it, or none of mine can do it.Most often used scope is HP and Siglent, just because one is side of my desk and one is in front of me. When you buy a scope at the price range you are talking about, there are things that are omitted, and performance is somewhat limited. Which one is better is really strictly personal preference.

author: bitseeker
author_rank: Super Contributor
timestamp: March 22, 2019, 08:53:11 pm
content: Quote from: Fungus on March 22, 2019, 09:25:04 amThat interpretation makes sense.QuoteYes, that's been my position as well. In a way, it makes choosing much easier than if they were also vying for the same price point.

author: SWR
author_rank: Regular Contributor
timestamp: March 22, 2019, 08:54:18 pm
content: Quote from: HalFET on March 22, 2019, 01:09:23 amI actually like the AWG and the DMM in the MDO-2204EX. Sure, it's not 6½ digit resolution, but it is actually pretty solid performance. I was pleasantly surprised that the metal joint thermistor temperature sensor had a selection of 8 different metal combination settings to match the different sensors I had lying around. Another convenience apart from having everything in one pachage to carry is that you can put the friggin display on the screen and save a screendump together with the scope picture and save it to the USB stick. It makes it much easier to get the readings into a report. I know many multimeters have digital connections, but a USB stick is just less complicated for me that setting up a connection and finding the right program/app for that particular instrument. I like to keep it simple. Taking pictures with your phone is also a drag.

author: BillB
author_rank: Unknown
timestamp: March 22, 2019, 09:11:41 pm
content: I hope OP hasn't been scared off, realizing he just dipped a toe into the shark tank.A nice feature of the Siglent scope I don't believe has been mentioned yet is the web interface. It's handy to remote control the scope from a PC web browser, and get a larger view of the scope display on my monitor.

author: nctnico
author_rank: Super Contributor
timestamp: March 22, 2019, 09:24:17 pm
content: Quote from: bitseeker on March 22, 2019, 08:53:11 pmI disagree. In many cases it is better not to get tempted to buy a low quality cheap tool which looks good on paper. In the end you'll realise you need a good tool to move forward and by that time you have wasted money on a cheap tool, accumulated a lot of frustration, wasted time and on top of that need to spend more money on a good tool.All in all the question is: what kind of budget do I need to buy a good tool which fullfills my needs.

author: james_s
author_rank: Super Contributor
timestamp: March 22, 2019, 11:24:29 pm
content: You could just flip a coin. Chances are you'll be happy with either one, they're both good entry level DSOs, just get one and then spend your time learning how to use it to the fullest rather than worrying about what you may be missing out on by not getting the other instead.

author: rhb
author_rank: Super Contributor
timestamp: March 22, 2019, 11:25:15 pm
content: One point in the Rigol's favor. They are popular and selling one would not be hard. The resale value should be very good. A DS0154Z is $375; a DS1052E is $259.With a tight budget I'd buy the DS1052E and, as much as I despise the company, a 30 or 60 MHz F***Tech FY6800 for $100-110 (do not get an FY6600!!!). I'd add a $20 BSIDE ESR02 Pro and a $10-20 DMM. That's around $400 and gives you all the essential measurement capabilities needed for basic electronics work. Add $100 in parts assortments, resistors, capacitors, transistors. op amps and a cheap ($20) copy of "Electronic Principles" by Malvino and Bates and in a year's time you will be quite skilled if you work through all the examples and exercises in the book.I have no intention of selling my DS1102E. It's a very good scope for the $400 it cost me. I no longer use it much, but it's more than adequate for a *lot* of work. It's also compact and solidly built. so I'm more likely to grab it if I'm trying to help someone sort out installing a dimmer on their boat than any of my other scopes.No matter what you buy. No matter what your budget. There will be issues whether bugs or bad design that will cause problems.A hacked DS1054Z will give you 100 MHz. A stock Siglent 1202X-E will give you 200 MHz as will a hacked SDS1104X-E. When I get some of my other projects finished I plan to put all the entry level DSOs in a task by task comparison against a Tek 485, LeCroy DDA-125, Tek 11801 and whatever else I have by then. I might even get inspired and resurrect my Tek 465 and Dumont 1060.The SA function on the Instek MDO is very good despite showing the series resonance of a crystal as a peak rather than a notch. The regular FFT on the other members of the GDS-2000E line are in the "it works, but it's really crappy" category. But the MSOX3000T and RTM3000 are in the "it doesn't work" category along with Rigol.

author: HalFET
author_rank: Frequent Contributor
timestamp: March 23, 2019, 01:01:17 am
content: Quote from: tautech on March 22, 2019, 07:34:00 pmMay I recommend a book on the concept of measurement uncertainty before we continue this conversation? That 8 bit ADC + a scope's noise tends to have a rather profound effect on the measurement error/uncertainty.As a result, these bode plot measurement systems are often nothing more than a gimmick, they'll give you something and might work semi-well to debug a very simple active filter. For anything decent you'll still need a true setup (i.e. function generator and a multi-channel high-speed voltmeter) Please don't try to represent this functionality as something it really isn't.Quote from: tautech on March 22, 2019, 07:34:00 pmOf course you do, you're trying to make a sale here.Quote from: tautech on March 22, 2019, 07:34:00 pmStop comparing apples and pears, that chart is incredibly biased and misrepresents the capabilities of the scope entirely. It's pure marketing wank of the highest order and by pointing it out I feel like I'm flogging a dead horse. But since you insist:Lets take the SDS1000X-E series from Siglent, some of the numbers on the datasheet seem rather ambitious, i.e. <100 ps channel skew on interleaved sampling seems awfully nice if you can't even guarantee the stability of your clock to that degree. (What happened there is that theyaccidentallyforgot to mention you got to lob that 25 ppm uncertainty on the timebase onto that number. )But what's really unforgivable is how they tacked on low voltage modes that probably don't exist. Ever wondered why the noise and error seems to differ when you dive under 5 mV/div? That's because the scope frontend is most likely incapable of actually doing these ranges and it's probably multiplying measurements at a higher range. Decent manufacturers like Keysight put the following warning in their manuals: "1 mV/div and 2 mV/div is a magnification of 4 mV/div setting. For vertical accuracy calculations, use full scale of 32 mV for 1 mV/div and 2 mV/div sensitivity setting."I could continue for a while, but I think you get the gist of this comparison? It's easy to claim you're awesome if you happen to have selective amnesia when writing datasheets.Quote from: Fungus on March 22, 2019, 07:45:04 pmMind you, that chart is still better than Siglent their datasheets, which is scary in a way...Quote from: SWR on March 22, 2019, 08:54:18 pmI can't comment on the AWG of that series, never got my hands on a recent GW Instek. But most of the built-in DMMs are hard pressed to reach even a true 3.5 digit measurement.And personally I just write down the number in my lab notebook, because the screenshot is usually more difficult to relate to what was happening on my bench at the time than my scribbles.

author: Aidanator7000
author_rank: Contributor
timestamp: March 23, 2019, 01:23:56 am
content: How about we actually get an opinion from someone who has actually used both scopes before rather than hearing the biased opinions of those who have one or the other. It's frustrating to see the same argument being had over and over again in so many different threads.My advice would be to go for what ever scope your gut says, at the end of the day either will do the job (or buy both)

author: HalFET
author_rank: Frequent Contributor
timestamp: March 23, 2019, 01:29:23 am
content: Quote from: Aidanator7000 on March 23, 2019, 01:23:56 amThat's pretty much my point.Go to an electronics tradeshow/fair/university lab where they happen to have both/... and try them out. Buy the one who's user interface you like the most, the performance is roughly the same of all these models anyway.

author: rhb
author_rank: Super Contributor
timestamp: March 23, 2019, 02:17:11 am
content: I've not tried the Bode plot on a Siglent yet. The Instek version is a joke. When I attempted a sweep from 13.3 to 13.6 MHz of a 40 MHz 3rd overtone crystal, I got 2 data points. One can do better with the MDO SA function, but it takes the square root of the power specrtrum, so the series resonance is a peak.However, a person with the requisite mathematical skills and the ability to transfer data to a PC can match the performance of *any* instrument up to the BW of the DSO and signal generator. My "To Do" list has writing the software for that close to the top. Fixing the Tek 11801 sampling scope I just bought and testing my SD-22 sampling heads are at the top with setting up my 8753B and 85046A close behind.

author: Fungus
author_rank: Super Contributor
timestamp: March 23, 2019, 06:41:08 am
content: Quote from: rhb on March 22, 2019, 11:25:15 pmA hacked DS1054Z is much closer to 200Mhz than 100Mhz. The Siglent is also well over 200Mhz.eg. 1.7ns rise time on a DS1054Z (as measured by TurboTom with his rubidium source):As mentioned earlier,boththose numbers are well into the area where you need to really know what you're doing in terms of probing and connecting the cables. You can't simply poke at a circuit with the supplied probes and get those results.Bandwidth shouldn't really be a factor when deciding between these two 'scopes, both have enough for everyday use, neither has enough for "serious" work.

author: Aidanator7000
author_rank: Contributor
timestamp: March 23, 2019, 07:03:22 am
content: Quote from: Fungus on March 23, 2019, 06:41:08 amAnd yet the argument can be made that the -3dB bandwidth of the 1000X-E is much greater than 200MHz... you just gonna keep going round in circles over and over again.

author: Fungus
author_rank: Super Contributor
timestamp: March 23, 2019, 07:06:13 am
content: Quote from: Aidanator7000 on March 23, 2019, 07:03:22 amUm, yes, I think I said that.

author: Aidanator7000
author_rank: Contributor
timestamp: March 23, 2019, 07:29:15 am
content: lol, sorry i missed that

author: TheNewLab
author_rank: Frequent Contributor
timestamp: March 23, 2019, 07:33:03 am
content: Quote from: Fungus on March 21, 2019, 09:19:10 pmBut hey, FFT ia fun to experiment with..it can give you new idaeas of how to scope and build projects...Doesn't both of them do FFT? even Hantek offers that feature.

author: TheNewLab
author_rank: Frequent Contributor
timestamp: March 23, 2019, 07:55:20 am
content: Just my two quid..do they still have quid??It is true that the Siglent can handle two channels and maintain 100MHz, only for me it was so fun to hac the Rigol. Despite it was just going to a key gen and enter a code...My experience is, I never intended to get so deep into electronics to buy such a piece of equipment. In fact, my orignal plan is to limit myself with an average DMM. It was to be a hobby in which I could blow off steam and something a could not, would not turn into a business...So for my health's sake.Long -story short. it took years to break down and buy a real oscilloscope. I just plunged into the Rigol 1054..it was such a great price, and learning it could be hacked just sounded fun. Then I came into some extra money that I could burn..and finding a scope that could really measure signals with accuracy..I began researching the Siglent...It seemed even better..able to have two channels at 100MHz, not dropping to 50MHz, that it included other forms of signal measurement. reading Can bus made me curious since I had just gotten back into auto repair..and updating myself with auto diagnostics..A used Prius.And I thought finally having a real logic probe included on a scope would be fantastic.Well, I found the logic probe of the Siglent is not so fantastic..What I am learning is that it is not so responsive and kinda of slow, and hard to read on the oscilloscopes screen. i never bought it and am now looking into a dedicated USB type of logic probe..I bought both. I enjoy both I use the Siglent more often..I like the larger screen and have not experiments with the CanBus feature.I do not know about the GWinstek, or the newer models that keep coming out. IMO I would set a price point 1st. a hard price point and I will bet you will still go over it. look at what you are doing, and what you would like to do...I was interested in being able to work with good old fashioned TTL digital IC's and I had a collection of Fast TTL 74F ones.One thing I did was not just price, but find and download the user manuals, however I kind of enjoy doing research into major purchases.Only other thing I can mention..be patient. not knowing and just fiddling with the features is where I started too. Still, think about what you imagine you might use it for, after you move beyond playing and discovering how to use it.Good luck, enjoy the journey!

author: rf-loop
author_rank: Super Contributor
timestamp: March 23, 2019, 08:30:19 am
content: Quote from: HalFET on March 23, 2019, 01:01:17 amRigol DS1000Z data sheet:Vertical Scale(Probe ratio is 1X) 1 mV/div to 10 V/div.And same data sheet claim 12 bit resolution (High res) what is bullshit. After High res, data resolution is still 8bit and nothing else and "8 - 12bit" is only for reduce noise on the screen.If look example some Tektronix they also use double bytes for keep high resolution averaging result data.They do not tell 1 and 2mV/div is derived from 5mV/div. (I have owned DS1000Z and also used it and 4 years ago proofed these 1 and 2mV are not full vertical resolution what was one show stopper together with enormous signal noise and total lack of measurements horizontal resolution "highly decimated data like just from screen")Siglent SDS1000X-E full resolution range starts from 500uV/div.How useful it is, it is other question but it is not digital magnification from less sensitive range.Images are from:https://www.eevblog.com/forum/testgear/siglent-sds1204x-e-released-for-domestic-markets-in-china/msg2102305/#msg2102305Quote from: rhbSDS1104X-E and generator SDG1032XWith Siglent you car run this using up to 500 steps (501 points)Minimum BW is 500Hz with minimum step 1Hzexactly same XTAL using 5kHz BW500 steps, 10Hz steps.Individual points in list.And of course Siglent FRA ("bode plot") have 3 simultaneous channels (+ref)Here this test setup was really poor due to device under test etc. Only what is tell is that there is 3 channel.

author: Fungus
author_rank: Super Contributor
timestamp: March 23, 2019, 08:58:54 am
content: Quote from: rf-loop on March 23, 2019, 08:30:19 amTrue.Quote from: rf-loop on March 23, 2019, 08:30:19 amThis is therealquestion.Siglent owners (and oscilloscope reviewers in general) love to zoom in and go "Ooooh! Look at that" but the reality is that 0.5V-1V/division is the usual setting and there's more than 1mV noise in just about everything you can poke at with one of those probes.(and the way to get rid of it is to use one of the hires/average modes provided by these 'scopes - providedfor a reason)

author: Fungus
author_rank: Super Contributor
timestamp: March 23, 2019, 09:22:27 am
content: Note that the probe was deliberately set to 1x mode to get these Rigol-hatin' results. This makes the noise 10x worse than you'll see in real life (in reality, 1x mode is somethingyou might never use in an entire lifetime of 'scoping). Divide those Vpp and RMS numbers by 10 for realioty.(Edit: Why all the 'history' and 'playback' modes in the Siglent? Does that improve the signal? Why not use the same modes on the Rigol? Suspicious...)nb. Dave did a whole video on the subject of 1x mode and the pitfalls/traps is has:

author: tautech
author_rank: Super Contributor
timestamp: March 23, 2019, 09:27:33 am
content: Quote from: Fungus on March 23, 2019, 09:22:27 amOh come on, pull the other one.Have you just turned up here and never checked for mV ripple on a PSU ?

author: Fungus
author_rank: Super Contributor
timestamp: March 23, 2019, 10:04:26 am
content: Quote from: tautech on March 23, 2019, 09:27:33 amThe sort of person who needs to accurately measure mV ripple on a PSU shouldn't be arguing over the differences between a $350 and a $500 oscilloscope, they should be looking at a professional tool.

author: Rerouter
author_rank: Super Contributor
timestamp: March 23, 2019, 10:20:41 am
content: Bit confused there fungus, measuring power supply ripple to multiple mV is well within the capacity of just about every scope I have used, You may need to cross check your measurements with an external wavegen if you need fractions of a single mV,Both the scopes showcased by the OP have at least 1 full division of resolution at 1mV, I cannot speak for the rigols noise. but the siglents is well low enough to measure better than 300uV if you spend a few minutes setting up the measurement.

author: Fungus
author_rank: Super Contributor
timestamp: March 23, 2019, 10:44:48 am
content: Quote from: Rerouter on March 23, 2019, 10:20:41 amYep, and probably more with the right combination of display settings.You normally want the BW limiter turned on in 1x mode, too, but the person who made that image didn't bother with realistic settings.Quote from: Rerouter on March 23, 2019, 10:20:41 amSo the question becomes: Is the purchaser of the 'scope likely to do that?If so, spend more money and get the Siglent.If not, get a Rigoland a decent multimeter(or whatever) instead. You'll be better off.This "eternal" argument only makes sense if they both cost the same amount of money.

author: Rerouter
author_rank: Super Contributor
timestamp: March 23, 2019, 11:09:17 am
content: there both entry model scopes, its not a question of whats unlikely, more, can it do what you want to do until you feel you have earned back its value through using it.was it likely that I would use the trigger out of my scope to fill the role of a thermostat until the part arrived? No, Am I happy I could do it, YesIf you want GHz scopes with crazy options for not much coin, you go dig yourself an ebay hole looking for them second or third hand, Heck for a high grade multi meter I got a tektronics 3 way mainframe and 3 DM5XX modules working for under $80, again is searching for these things worth it to you, and can the tool do what you want to accomplish without too much fiddling.In my book, if you need to document things, the siglent may be more convenient, you can just spam the save as PNG and save .bin file buttons from the web interface. Vs the intermediary step of using a USB drive. the lack of an RTC is a pain, but there are commands to set the time and date for the session you have it powered up so things get time stamped correctly.Again this is without me having used the rigol, I almost certainly have some level of bias,

author: HalFET
author_rank: Frequent Contributor
timestamp: March 23, 2019, 11:10:03 am
content: Quote from: rhb on March 23, 2019, 02:17:11 amSurprisingly, the cleanest and quickest solution is often still just writing down the points and sketching it yourself. And especially for beginners this is important, it's good to know what's actually going on. That way you can point out when something goes haywire.Quote from: Fungus on March 23, 2019, 06:41:08 amWhy do you need a rubidium clock for a fast rise time pulse? But anyway at 100 MHz you don't have to be that careful with probing, the thing is that both of these scopes their response curves won't be flat once you go above 75% of the "design bandwidth". Grab a decent RF generator and sweep at a constant power, you'll see interesting things happen. Do make sure to hook it up properly though! In practice both these scopes are limited to practical signals of around 70 MHz anyway, anything above that and you lose too many harmonics to still see what's truly going on. That third harmonic is really nice to have if you want to actually see something.Welcome sir rf-loop, I was expecting your appearance in this false marketing show! Let me start by saying that Chinese companies still haven't learned that engineers are capable of reading through bullshit datasheets anyway, so mentioning higher numbers doesn't actually convince them. People buy HPAK, Keysight, R&S and others because their equipment actually meets the specifications they list on their datasheet. In fact, every single HPAK scope I've bothered to gauge the performance of significantly outperforms the datasheet. Meanwhile, the Rigol and Siglent units on the other hand barely make ends meet. Furthermore, the major manufacturers seem to be capable of running spellcheck on datasheets, that way you don't end up with "channe:" and other fun things like that. In short, both Siglent and Rigol have craptacular datasheets.Quote from: rf-loop on March 23, 2019, 08:30:19 amWhat does the probe ratio have to do with this? Do you actually understand what you're reading on datasheets?And their 12 bit can actually be 12 bit, it's called oversampling and you can implement it in an oscilloscope. You can directly group samplings of the ADC and average them out (or better yet, interpolate them properly), this will decrease the uncertainty of the measured voltage significantly and grant you extra resolution. A better tactic which is a bit more difficult to analyse is using multiple waveform captures in a row and averaging those out. In that case the actual resolution also depends on the repeatability of the trigger and timebase stability. But I'll agree it's bad practice to just slap a number on it. However, Siglent does pretty much the same thing for other values on their datasheet (i.e. delta error between channels or when making phase measurements) so you don't get to use this as an argument against Rigol. You could have easily pointed out that their DC gain and offset definition is less precise, but they don't try to cut it up into as many chunks as Siglent to make the unit look more impressive than it is.Quote from: rf-loop on March 23, 2019, 08:30:19 amAnd these images prove exactly nothing, the settings were cherry picked to get that result. And testing the noise on scope frontends with no short probe or BNC short attached to them is a bit of a joke given their input impedance.All you show is that they have a different way of displaying noisy signals. Furthermore, the Keysight unit shows the quantisation quite clearly, as it should. That's the scope holding up a sign with the following message: "Hey, we're running into the limit here, I can still show you some data but you'll have to figure out what it actually means." Neither the Swiglent or Riggedol pass the test by this metric.Quote from: rf-loop on March 23, 2019, 08:30:19 amAgain, what is the error on this measurement? You keep showing fancy plots but can never quite explain the numbers behind them. I wouldn't be amazed if you have 10%, or more, error on that measurement you're showing.Quote from: tautech on March 23, 2019, 09:27:33 amA scope is the wrong tool for that job... Try again please.Quote from: Rerouter on March 23, 2019, 10:20:41 amYour measurement is meaningless though. It showssomethingon the screen, sure. What you're actually seeing is a good question, my bet is that it might have more in common with the cosmic microwave background than with the actual signal.It'd be fun if someone rewrote the firmware of these scopes to indicate the uncertainty bounds on the measured signals, I think people would be unpleasantly surprised.

author: gf
author_rank: Super Contributor
timestamp: March 23, 2019, 11:38:42 am
content: Quote from: Fungus on March 23, 2019, 10:44:48 amThe question is, whether the BW limit really makes a difference for the Rigol's noise floor, does it? On my Hantek 6074BD the BW limit reduces only noise present in the captured signal, but not the noise floor of the scope.The most obvious reason is that the noise floor is dominated by ADC noise, and not by noise from the frontend (at least the dominant component of the noise floor is obviously introduced after the BW-limit filter). Hereby it is noteworthy that this scope makes full use of the HMCAD1511's "digital gain" feature. 2mV/div is not achieved by higher analog gain, but 2mV/div is in fact the same as 100mV/div in the frontend, with 50x digital gain in the ADC.[ Fully utilizing the HMCAD1511's features certainly enables the simple design of this frontend: Two relay-switched 10:1 attenuators at the input (-> 100:1/10:1/1:1) => FET buffer => ADC driver (fixed gain of only ~2) => HMCAD1511. No need for variable gain amp or analog multiplexers. ]As far as i know, both, the Rigol and the Siglent use the HMCAD1511 as well, but I don't know whether either of them also makes (full) use of the ADC's "digital gain" feature as well. A BW-limited analog pre-amp stage can IMO well result in a lower noise floor than using digital gain of HMCAD1511 (the latter is likely only as usefull a claimed by the datasheet, if full BW is required, so that a BW-limited pre-amp is not an option).

author: Rerouter
author_rank: Super Contributor
timestamp: March 23, 2019, 12:16:24 pm
content: Ok, I'll give you at least what I can, Turning off the nearby electronics doesn't change it that much, So I'll call it my baseline.Turning the thing on, in my 24C room, a few weeks since I last ran self-cal, image 80 is what I get, all inputs are open, and set to DC 1M with a 20Mhz limit, you can see the offset does drift a little with time and temp.Leaving it for 30 minutes to "warm up" does not change it by any significant amounts. running self cal brings the dc offsets back in line. it can be trimmed better based on the DAC in the front ends, and I have made Siglent aware. Image 81,In this configuration, (100ms Tdiv, 500uV Vdiv, 7M samples)all channels have 500-560uV of peak to peak noise, standard deviation between 50-54uV,Adding 50 ohm terminators to the front BNC jacks reduces that to about 460uV peak to peak, and about 42uV standard deviation.These measurements are made with the channel VGAC at a gain of 25db I cannot say if that is anything you can use in your math, and I can ramp that up to about 35db gain if it helps your comparison.

author: Rerouter
author_rank: Super Contributor
timestamp: March 23, 2019, 12:42:25 pm
content: Scaling up the VGAC gain still gives practically the same values, So i would also pin it on ADC being the noise source,at VGAC 35db gain, i measure 560uV of peak to peak noise, and a standard deviation of 54uVPutting on the 50 ohm terminator brings it down to 450uV of peak to peak noise, and 43uV standard deviation.I'm also happy that previously I misread the specs of the VGAC, so max VGAC gain is actually more like a 200uV range.

author: Fungus
author_rank: Super Contributor
timestamp: March 23, 2019, 01:01:35 pm
content: What do you getwithoutthe 20Mhz limiter?

author: gf
author_rank: Super Contributor
timestamp: March 23, 2019, 01:07:39 pm
content: Quote from: Fungus on March 23, 2019, 01:01:35 pmExactly, it would be interesting whether the noise floor ofthisscope does profit from the BW limter, or not (as said, my scope does not).

author: Fungus
author_rank: Super Contributor
timestamp: March 23, 2019, 01:15:36 pm
content: FWIW my Rigol gives this with nothing connected to the inputs:If I turn off the BW limiter the VPP goes up by about 100uV (20%). Offsets are there because the 'scope has only been on for a minute or so.I have no idea what the Siglent boys were doing to get this:

author: Rerouter
author_rank: Super Contributor
timestamp: March 23, 2019, 01:20:36 pm
content: without 20Mhz limiter, and unlocked to 200MHz, All channels 880-920uV peak to peak, 83-84 stdev,Fitting a 50 ohm terminator is 840-860uV pk-pk, and 81 for standard deviation.Bumping the gain up to 35db,1M inputs,890uV pk-pk, 90 stdev50 ohm terminator,860uv pk-pk, 87 stdev

author: HalFET
author_rank: Frequent Contributor
timestamp: March 23, 2019, 01:24:44 pm
content: Quote from: Rerouter on March 23, 2019, 12:42:25 pmThis is bad measurement to gauge a scope's performance. You can quite easily doctor these things to the point that it's entirely meaningless, especially once you start playing with the acquisition settings. Since you folks keep insisting, let me demonstrate with a DSOX2012A. Please note that my point here is to actually show what I'm doing, you can perfectly hide what you did if you really insist on it. This is what you get if you put the scope in its 10 mV/div range with a 100 ms/div time base immediately after turning it on:Lets now turn on high-resolution mode:But lets say we want to push it even further, lets turn on averaging (8 waveforms):But since we're doing useless pointless measurements, why not go for the entirely ridiculous settings:Now I could have hid what I did there and have claimed that Keysight makes scopes with a 26 µV noise floor. Could have probably gotten it closer to zero if I had bothered to find a short BNC terminator. Also note how the ADC on an Agilent scope doesn't need to run nearly as fast, which might give you a bit of a hint about what's actually going on here. Which is to say: pointless measurement.

author: Fungus
author_rank: Super Contributor
timestamp: March 23, 2019, 01:29:42 pm
content: Quote from: Fungus on March 23, 2019, 01:15:36 pmWait, yes I do! I fiddled around and found I can get their display if I zoom out and don't adjust the persistence. Here's two views of the exact same thing with different horizontal timebase:Theylookcompletely different! In reality it's just the way the data is presented on screen. The first picture is the more correct display and also the most natural one in use.(zooming in on signals is the most natural thing to do when you're using a 'scope).nb. It's well known that the DS1054Z calculates RMS using the on-screen data so thatalsoexplains their "suspicious" numbers on screen. They either don't know how to use a Rigol or they're willfully ignoring that detail.

author: gf
author_rank: Super Contributor
timestamp: March 23, 2019, 01:35:22 pm
content: Quote from: Fungus on March 23, 2019, 01:15:36 pmBut when I see 1.36mV pp vs. ~450uV pp in the two screenshots, then it is rather a factor 3 (and not just 20% more)?So obviously the BW limiter does help here.

author: Rerouter
author_rank: Super Contributor
timestamp: March 23, 2019, 01:36:18 pm
content: I gave both as reference, the VGAC comes before the ADC, i have the datasheet for the chip, and A way of reading and writing to its gain register,https://www.analog.com/media/en/technical-documentation/data-sheets/ad8370.pdfAfter self cal, 500uV range is a High gain code of 45, I was raising this to a high gain code of 127,Acquisition has no averaging or eres turned on, no persistence, just dots mode, with things left to sample about 10 times before I collected my ranges over lets say 5 sampling windows.My limited understanding has it that if increasing the gain of your preamp by 2.5 times and there is no change the noise measured, then it must be after that point that the noise is occurring, The input terminator was to try and isolate the contribution of noise from the 1M input impedance.please if you feel there is a better way to determine the noise source in the front end chain, I would be interested,Edit: Attached is an image of the noise after I manually set the VGAC, all values measured are off by 8db, or a scaling factor of 2.51, as the scope UI doesnt know that I rescaled it. This was how I was measuring those values,

author: Fungus
author_rank: Super Contributor
timestamp: March 23, 2019, 01:40:12 pm
content: Quote from: gf on March 23, 2019, 01:35:22 pmThe 1.36mV isn't my number - see my later post on display zoom for explanation of where that number likely comes from.The 20% comes from enabling/disabling the BW limiter without changing horizontal timebase.

author: Fungus
author_rank: Super Contributor
timestamp: March 23, 2019, 02:02:13 pm
content: If I was really interested in looking at PSU ripple (ie. not background/ADC noise) I'd be using either averaging or hires modes. That's what they're for.

author: gf
author_rank: Super Contributor
timestamp: March 23, 2019, 02:17:23 pm
content: Averaging makes only sense, IMO, if the signal is periodic and if you have a stable trigger. Then it decreases the random noise and retains the non-random components of the signal.[ Well, it may be non-peridoc, if the waveform in the time window around the trigger point is the same at each acquisition. ]Hi-res, on the other hand, is basically oversampling + decimation with a box filter. So it does neither require a periodic signal, nore a stable trigger.

author: gf
author_rank: Super Contributor
timestamp: March 23, 2019, 02:48:20 pm
content: Quote from: Rerouter on March 23, 2019, 01:36:18 pmJust a brief calculation:In order to raise 500uV/div (which is about 5mV pp full-scale) to the ADC's 2V pp full-scale input voltage, a gain of 400V/V is required. If the VGA is limited to ~50V/V, then either an additional amp stage were required, or the ADC still needs to be operated with 8x digital gain. But only 8x - at this "low" gain level the HMCAD1511 noise is supposed to be still pretty good (seehttps://pdfs.semanticscholar.org/6063/513875078a4f4f6759895c1982d31fe5f53a.pdf).

author: Fungus
author_rank: Super Contributor
timestamp: March 23, 2019, 03:21:34 pm
content: Quote from: gf on March 23, 2019, 02:17:23 pmThat's why I said either/or.Ripple is quite often periodic though.

author: rf-loop
author_rank: Super Contributor
timestamp: March 23, 2019, 03:31:52 pm
content: Quote from: HalFET on March 23, 2019, 11:10:03 amIf you did not understand what means sentence "Rigol DS1000Z data sheet:" then I'm just so sorry. Perhaps it need bend using iron wire. If I write what reads in Rigol data sheet and then you wonder like teenager in school why it include what is printed in data sheet... It is there because I quoted 1:1 Rigol data sheet. Ask Riglol why they write it. (But I understand also why they write it there, sorry if you not.)Is it now better:Quote from: Rigol DS1000Z data sheetAs can see in attached image.If I quote data sheet it is not my habit to selectively remove or edit something what is there.But yes, I have not fully understood every single databook and datasheet what I have read during over 5 decades hobby+work with electronics but even after this, many things and machines still works in industry even in mil sector even today what I have done. Perhaps only good luck...or perhaps also because I read data sheets beforehand and not only after somethings goes wrong. "first brain, then muscle"But it feels very nice that today I'm retired because If I need read seriously for work today's many data sheets etc...responsibility has been passed on to the reader just as the listener has full responsibility when the politician speaks.

author: HalFET
author_rank: Frequent Contributor
timestamp: March 23, 2019, 03:56:39 pm
content: Quote from: gf on March 23, 2019, 02:17:23 pmOf course averaging doesn't make sense in most cases, but then again, neither does this measurement. The premise of using a plain scope without an amplifier for a low noise measurement is bonkers to begin with.Quote from: rf-loop on March 23, 2019, 03:31:52 pmThen quote a relevant part, like the measurement uncertainty. All you did was say that it has a 1 mV/div to 10V/div range, which is entirely meaningless for this discussion.Quote from: rf-loop on March 23, 2019, 08:30:19 amAre you using Google translate? :|

author: rhb
author_rank: Super Contributor
timestamp: March 23, 2019, 04:25:32 pm
content: In general, unless the noise is a zero mean Gaussian process, averaging will distort the waveform. I apologize for not being interested enough to go through all the many probability density functions to enumerate those which are not zero mean.A Gaussian assumption is often, but not always valid.A cheap DSO in good hands can do amazing things. The Owon XDS1202A will give a skilled user over a 100 dB dynamic range. However, you will need to understand discrete time signal processing to get that level of performance. And be able to implement the required operations.I am pleased to see that Siglent got scalar network analysis correct. That increasingly inclines me to get an SDS1104X-E and do a comparison of Rigol, Instek, Owon and Siglent entry level DSOs against a Tek 485, LeCroy DDA-125/LC684DLX and Tek 11801. Every one of those can do things which the others cannot. And all (except for the 485) of them have FW features which are incorrectly written.

author: rf-loop
author_rank: Super Contributor
timestamp: March 23, 2019, 06:48:55 pm
content: Quote from: HalFET on March 23, 2019, 03:56:39 pmAnd you did not even note what they did not tell... and it was point (of course)I think it is also important to observe what has not been said.Is it meaningless that Rigoldo notgive any info that there is no true 1mV or 2mV/div but they are magnification from 5mV/div range.But then you take example how Decent manufacturers like Keysight are good because they tell.Perhaps you forget this your own or do you tell now that all this is also meaningless.Quote from: HalFET on March 23, 2019, 01:01:17 am

author: gf
author_rank: Super Contributor
timestamp: March 23, 2019, 06:53:10 pm
content: Quote from: rhb on March 23, 2019, 04:25:32 pmThe PDF does not really matter.Averaging is a linear operation, i.e. we can treat averaging of the noise component and averaging of the wanted signal component separately, and then add the two results.Averaging N copies of the (non-random) wanted signal component y(t) still results in y(t) - that's identity - there won't be any distortion per se.Non-zero mean of the noise is not really an issue either - it's just a DC offset, but does not affect the waveform's shape otherwise. For averaging the AC noise component, the Central Limit Theoerm applies. If more and more independent randeom variables are added (ragardless of their PDF), the PDF of the sum tends toward a Gaussian distribution, i.e. the resdiual noise after averaging will be closer to Gaussion and will have a lower standard deviation than before averaging.However, the wanted signal component gets indeed distorted, when the N averaged copies arenot exactly time-aligned, due to triggering jitter, which is predominantly a consequence of the noise as well. Low-pass finltering of the trigger path may help. An even better alignment could be achieved by calculating cross correlation and finding the time offset which gives the best match of the waveforms - but that's computationally expensive.

author: rhb
author_rank: Super Contributor
timestamp: March 23, 2019, 07:38:51 pm
content: Quote from: gf on March 23, 2019, 06:53:10 pmYour statements assume a noise process with a flat spectrum. Many noise processes such as 1/f noise do not have flat spectra. If your assertions were correct the seismic processing community would not have spent millions of dollars developing the huge suite of noise suppression algorithms that are in current use.I suggest buying a copy of:Random DataBendat & Piersol4th ed Wiley 2010That has been my primary reference for classical Wiener signal processing since I bought the 2nd edition in the late 80's.Time aligning multiple sweeps is actually trivially simple. I plan to write software to do the process below to increase the dynamic range of TDR traces collected with a DSO and pulse generator to perform vector network analysis up to the BW of the DSO. With a 12 bit trace from an Owon XDS2102A a single 20 Mpt trace will provide over 100 dB of dynamic range. With an 8 bit ADC one simply needs more samples.Segment the record into individual sweepsZero pad to 2x or longer and Fourier transformPerform a linear fit to the phaseAverage the phasesApply phase shifts to each sweep to shift it to the average phaseSum the transforms but do not divide by the number of sweeps.Inverse transformEvery doubling of the number of sweeps yields an extra 6 dB of dynamic range

author: Fungus
author_rank: Super Contributor
timestamp: March 23, 2019, 08:10:45 pm
content: Quote from: rhb on March 23, 2019, 04:25:32 pmIn this particular case it seems most of the noise is internal to the scope so the assumption is valid (or very very close to valid).More important is that the ripple waveform is truly periodic with zero modulation. You should use the waveform record/playback functions to confirm this before enabling average mode.Quote from: HalFET on March 23, 2019, 03:56:39 pmThat doesn't stop it from being trotted out in every single "Rigol vs. Siglent" thread.As we've seen today though, the Rigol doesn't have as much noise as the Siglent boys like to pretend. Their famous screenshot turned out to be just a pathological comination of the Rigol decimation combined with measurements based on screen date. Twist the timebase knob to a more "natural" value and it vanishes(which most people will do, as soon as you see noise on screen thenaturaltemptation is to zoom in a bit for a closer look).

author: gf
author_rank: Super Contributor
timestamp: March 23, 2019, 08:54:46 pm
content: Quote from: rhb on March 23, 2019, 07:38:51 pmI'm assuming uncorrelated noise, where each sample is randomly drawn from a given PDF, indepedent of previously drawn samples. Seems to be a reasonable assumption/approximation for the kind of noise being decussed (i.e. the wide band noise floor of scopes).QuoteI agree, but FFT costs quite some computing resources. My understanding is that usually the "averaging acquisition mode" simply aligns those points in time, where the trigger did happen to fire. That's computationally much cheaper (-> just average the buffers as acquired). But given a noisy signal, the trigger does not necessarily fire at the same point of the waveform for each acquisition.

author: Rerouter
author_rank: Super Contributor
timestamp: March 23, 2019, 09:02:56 pm
content: Quote from: gf on March 23, 2019, 02:48:20 pmOk, I'll pay there, so 5mV input scale, default VGAC is x17.8, so 89mV scale, the ADC also has a x50 internal amplifier, but we only need to use it with a gain of about x20 to get a scale of 1.78V, seems this may be how they have done it.

author: gf
author_rank: Super Contributor
timestamp: March 23, 2019, 09:44:32 pm
content: Quote from: Rerouter on March 23, 2019, 09:02:56 pmMy understanding is that the HMCAD1511 does not have an internal (analog) amplifier, but it rather has a higher (more than 8 bits) internal ADC resolution, and a digital multiplier between ADC core and digital output. It never outputs more than 8 bits, though. Implementation details are not given in the datasheet.Quote from: Application Notes

author: rhb
author_rank: Super Contributor
timestamp: March 23, 2019, 10:27:31 pm
content: I will post some screen dumps later of the Instek SA app with the inputs terminated in 50 ohms. The noise is not even remotely "flat".I invite anyone with a Siglent to do the same, especially below 1 MHz. The Rigol will require transferring the data to a PC.The averaging I described may not be practical on a DSO. I'll know a lot more once I've developed the FOSS DSO FW stack I'm working on.I'm fed up with crappy FW on DSOs even from the A list OEMs. I think the best way to address that is to run the exact same tests on multiple low end DSOs and put them out for all to see.

author: Rerouter
author_rank: Super Contributor
timestamp: March 23, 2019, 10:41:54 pm
content: rhb, if you can better explain what setup you want things measured under, I can likely do it, my crude understanding is your asking for an FFT of the noise?

author: gf
author_rank: Super Contributor
timestamp: March 24, 2019, 12:15:32 am
content: Quote from: rhb on March 23, 2019, 10:27:31 pmI find the noise floor of my cheap Chinese scope white enough (see attachment).EDIT: Id did try various sampling rates, down to 1kSPS, but the picture did not change significantly.But I'm not sure what you're really after. Even if it were not white - so what. Averaging does not make pink noise white, but it still reduces its amplitude.[ BTW: The two peaks at fs/2 and fs/4 are ADC interleaving spurs. ]

author: rhb
author_rank: Super Contributor
timestamp: March 24, 2019, 12:16:31 am
content: Yes. Plot the FFT of the noise at various sampling rates.In particular look at the FFT of the noise with a 2 MSa/s sample rate. That's where you will see all the SMPS noise. But you will find strong spurs at a wide range of frequencies. Average as many noise traces as you can using auto triggering and and a 10k to 100k record length. There is a tradeoff between longer records which give finer RBW and shorter records which give lower variance estimates.

author: Rerouter
author_rank: Super Contributor
timestamp: March 24, 2019, 12:46:45 am
content: Here you go, Have fun, At shorter Tdiv the samples start decreasing, but feel it covers what your asking for.

author: nctnico
author_rank: Super Contributor
timestamp: March 24, 2019, 12:51:11 am
content: Quote from: gf on March 23, 2019, 02:17:23 pmLeave the IMHO out. Averaging will only work well on a purely periodic signal.QuoteWhich is why the GDS1054B is such a good choice: it has input filtering so you can throw out any part of the frequency domain you are not interested in.

author: rhb
author_rank: Super Contributor
timestamp: March 24, 2019, 01:12:55 am
content: @rerouter Thank you! That is precisely my point. Those spectra are anything but white. The issue with the spectrum @gf posted was the variance of the spectral estimate was too large to show the problem.Your plots show that Siglent has done a much better at suppressing SMPS noise than Goodwill Instek. However, I should note that there is no way to know how many of the spurs are internal and how many are environmental EMI. I've had huge problems with conducted mode EMI radiating from the power lines.You just sold a Siglent SDS1104X-E! That and the Bode plots of crystal resonance will make it easy to hold several Chinese OEM's feet in the fire. I have no preference. My goal is to force the OEMs to improve their products. After 37 years of DSP I know how to break almost everything. And the rest just require more thought. TANSTAFL.@nctnico Averaging is only guaranteed to work if the underlying noise process is zero mean Gaussian. This is abused so much I refer to it as "sprinkling Gauss water on the problem".

author: nctnico
author_rank: Super Contributor
timestamp: March 24, 2019, 01:18:58 am
content: @RHB: I think you are mistaken averaging and oversampling. Averaging just serves as a low pass filter. For oversampling you'll need Gaussian noise and a linear ADC (which usually isn't the case).

author: rhb
author_rank: Super Contributor
timestamp: March 24, 2019, 01:32:56 am
content: c.f. Bendat & Piersol

author: gf
author_rank: Super Contributor
timestamp: March 24, 2019, 08:21:52 am
content: Quote from: rhb on March 24, 2019, 01:12:55 amI think I understand your desire now - you were interested in thenon-randomnoise components injected somehow into the front end.Overall, I'd say that the white noise power still dominates in the posted figures. But that's the nice thing of FFT, given enough sampes, it can pick out small periodic signal components from a swamp of random noise

author: gf
author_rank: Super Contributor
timestamp: March 24, 2019, 08:35:36 am
content: Quote from: nctnico on March 24, 2019, 01:18:58 am"Perfect" averaging is per se not a low-pass filter operator. The blurring effect is IMO caused by imperfections, namely by small time mis-alignment of the acquisitions being averaged.

author: gf
author_rank: Super Contributor
timestamp: March 24, 2019, 09:00:10 am
content: Quote from: rhb on March 24, 2019, 01:12:55 amWhat exactly do you mean with "work"?Which properties must the averaging fulfil in order that you call it "working"?[ If the only aim is to make the central limit theorem apply, then i.i.d. (i.e. white noise) should be sufficient. ]

author: nctnico
author_rank: Super Contributor
timestamp: March 24, 2019, 10:32:58 am
content: Quote from: gf on March 24, 2019, 08:35:36 amThe question is whether these imperfections are actually visible given the resolution of the oscilloscope display and ADC resolution.

author: Rerouter
author_rank: Super Contributor
timestamp: March 24, 2019, 10:44:57 am
content: If you really wanted a filter, you can still use the Fourier transform to act as what ever filter coefficient you want, you just loose a lot on the update rate to do it as it means more processing.Technically its not outside the capability of these devices to do an after the fact arbitrary type of filter, There is defiantly software room to run it, though no idea if the existing FFT function blocks in the FPGA could be re purposed to speed it up.rhb if you really are looking into open source firmware development. well there is a request.

author: rhb
author_rank: Super Contributor
timestamp: March 24, 2019, 12:59:25 pm
content: I simply wanted to point out some fine points of mathematics that are being blurred with a sprinkle of Gauss water. I'll let anyone interested in a refresher course consult Bendat & Piersol.There is nothing wrong with trace averaging. I use it all the time. But I am also acutely aware of its limitations.The FOSS DSO FW stack for Zynq and Cyclone V FPGAs I am working on will permit applying an arbitrary set of operations to the input traces a la LeCroy, low pass, high pass, band pass and band reject, trace integration, etc. But don't hold your breathe. I'm 1/2 way through "VLSI DSP Systems" by K.K. Parhi and will need to make a second pass. There are a lot of transformations for speeding up DSP that do not appear in general purpose CPUs. So despite having read the first 3 editions of Patterson and Hennessy over the years, there are a lot of considerations that are new and will require considerable study.I have a lot of reading to do before I go back to reading the books on FPGA implementations of DSP on FPGAs and Zynq and Cyclone V documentation. Faced with somewhere in excess of 10,000 pages of text to navigate, I'm getting very concerned about how I find things when I want to recheck my memory of what they said. The various aspects of this project are much more tightly coupled than what I've done in the past.

author: gf
author_rank: Super Contributor
timestamp: March 24, 2019, 03:37:55 pm
content: Quote from: nctnico on March 24, 2019, 10:32:58 amWhen I trigger a noisy signal, and the trigger is basically stable, but the displayed waveform still jitters a little bit horizontally around the nominal trigger point, then I'm inclined to say that I can see this jittering.This timing jitter leads to mis-aligned averaging of acquisitions (when averaging is turned on), which in turn makes averaging behave like a convolution. That's IMO the indirection how the low-pass filter effect develops which you did associate with averaging initially.

author: tautech
author_rank: Super Contributor
timestamp: March 24, 2019, 06:51:03 pm
content: Quote from: gf on March 24, 2019, 03:37:55 pmBut it's not, it's the trigger re-triggering on a non-repetitive waveform.Perfectly normal.To address this we either change the Holdoff and/or engage other trigger conditions to get stable triggering.A not perfectly stable waveform doesn't matter to much for general scope work but for accurate consistent measurements it does.An example, related to triggering on a glitch but using some tricks to find it, trigger on it and find its repetitive frequency using Search:https://www.eevblog.com/forum/testgear/siglent-sds1204x-e-released-for-domestic-markets-in-china/msg1370717/#msg1370717

author: gf
author_rank: Super Contributor
timestamp: March 25, 2019, 07:17:14 pm
content: Quote from: tautech on March 24, 2019, 06:51:03 pmI mean something different. Assume a sine wave signal. If it is noise-free then its (say) rising edge always crosses the trigger level at (almost) exactly the same phase angle of the sine wave. If I add a significant amount of noise, then the edge of the noisy sine wave signal is no longer supposed to cross the trigger level at exactly the same phase angle of the sine wave at each acquisition. The comparision of the noisy sine wave edge with a given trigger level eventually "converts" amplitude noise into trigger-jitter. Steep edges are certainly less affected than edges with only a modest slope.

author: ebastler
author_rank: Super Contributor
timestamp: March 25, 2019, 07:26:53 pm
content: Quote from: gf on March 25, 2019, 07:17:14 pmIf I understand your description correctly, in the situation you describe the sine signalshouldshow some jitter on the screen, right? You have added noise to your signal, so the point in time when the signal crosses the trigger threshold will vary; this will not always happen at the same phase angle of the sine wave.I thought we were discussing imperfections of real-world scopes here, but that does not seem to be what you are talking about here. Or did I misunderstand? If you had an "ideal", perfect scope, what would you expect to observe if you feed it a signal as described?

author: gf
author_rank: Super Contributor
timestamp: March 25, 2019, 07:33:05 pm
content: Quote from: Rerouter on March 24, 2019, 12:46:45 amI'd like to ask, how is the dB scale of these FFT plots supposed to be interpreted?Or in other words, what is the 0 dB reference level?

author: gf
author_rank: Super Contributor
timestamp: March 25, 2019, 07:37:43 pm
content: Quote from: ebastler on March 25, 2019, 07:26:53 pmLet me very briefly summarize the whole story I wanted to tell:1) the "imperfection" is noise (not I, but the scope adds it)2) noise leads to trigger-jitter3) averaging time-shifted acquisitions (due to trigger-jitter) turns averaging into a convolution (-> low-pass effect)EDIT:The origin wasQuote from: nctnico on March 24, 2019, 01:18:58 amwhere I answered that an averaging operation is not a low-pass per se, but indirectly it can be...

author: gf
author_rank: Super Contributor
timestamp: March 25, 2019, 08:40:50 pm
content: Quote from: rhb on March 24, 2019, 01:12:55 amHere is a better one, calculated offline with Octave from 64k points @ 2.5MSPS, 2 mV/div, normal acquisition mode, no BW limit.0 dB = highest peak in the spectrum, which is ~125 uV DC (offset error)Frequency scale is in MHz.I have no idea where the 500kHz spur is coming from.I guess (but I'm not sure) that the spur at ~1.9 kHz might come from the (PWM-driven) offset control feeding into the frontent.

author: rf-loop
author_rank: Super Contributor
timestamp: March 25, 2019, 09:48:57 pm
content: Quote from: gf on March 25, 2019, 07:33:05 pmIn @Rerouter images it looks like he have selected dBVrms.So "0dB" is 1VrmsIf select external load impedance (it can adjust between 1ohm to 1Mohm in SDS1000X-E) then there can use dBm "0dB" is 1mW (In SDS1000X-E impedance (external load) can set from 1ohm to 1Mohm.I hope Siglent add these units to display so that they are visible on screen independent of what bottom screen menu is selected.Images from 2017 manufactured SDS1104X-E mod1204X-E.

author: Fungus
author_rank: Super Contributor
timestamp: March 25, 2019, 10:42:43 pm
content: Quote from: gf on March 25, 2019, 07:37:43 pmNobody's denying that but in practice it works quite well.

author: HalFET
author_rank: Frequent Contributor
timestamp: March 26, 2019, 12:43:29 am
content: Quote from: rf-loop on March 23, 2019, 06:48:55 pmWhile I love how you're desperately attempting to shift attention away from how crappy Siglent is, it ain't working. I said both Rigol and Siglent are crap at making datasheets. If I was talking to a Rigol distributor I'd mention the flaws in their datasheet, though I must say they at least seem to be capable of performing an error calculation, didn't add a ridiculous 500 µV/div mode to look better and stuck to a realistic limit for the frontend. This is once again a demonstration why you won't find any Rigol or Siglent gear in professional environments, a company that realised what it was building wouldn't try to put such a mode in their scopes in the first place. Want to know why? Calculate the thermal noise a regular X10 probe throws off at room temperature and you might understand why microvolt level measurements are a bit futile...Quote from: Fungus on March 23, 2019, 08:10:45 pmOf course they keep highlighting that specific aspect, because they can't actually beat R&S, GW, HPAK, Tek, Lecroy, etc. at performance. So instead it's far easier to just come up with a crappy test like this which will convince their main non-educational customer base (Arduino nutcases). But I'm fairly certain the timebase stability of the Rigols I've had the "pleasure" of using at a local hackerspace doesn't actually meet the +/- 25ppm spec, or at least it was way worse than any HPAKs or Teks I've ever used.Quote from: Rerouter on March 23, 2019, 09:02:56 pmMost likely it's really just a digital multiplication. If you actually add it in properly it's going to make for one heck of a scope frontend design challenge. There's a reason the mainstream manufacturers don't bother with it...Quote from: nctnico on March 24, 2019, 12:51:11 amI find it also works reasonably well to catch certain types of periodic glitches in a high-speed bus, but then it needs to be able to trigger on the bus signals correctly.Quote from: rhb on March 24, 2019, 01:12:55 amNot really, if you get to deal with someone who knows their field they'll just point out the potential measurement error on the scope and state that it's not proof of component quality.

author: rf-loop
author_rank: Super Contributor
timestamp: March 26, 2019, 07:46:11 am
content: Quote from: HalFET on March 26, 2019, 12:43:29 amFutile and futile... of course I have knocked my head to thermal noise when I was young and play with some radio's in 60's.Of course with these entry level scopes, example Siglent, really can not accurate analyze signals in microvolt range - naturally and because basic level fundamentals. All know this and no one try talk that impossible is possible.But, still with it and some others can do something more than nothing.Take lowest price range Keysight and try this. I can tell to you, result is nada. But still with this cheap entry level scope can see this. Try with Keysight, result, nothing.Also previously shown FRA example with some xtal, try with double priced Keysight. Result: nothing.And if you think A brand did not implement 500uV/div to 1Mohm scope front end... bullshit.Take example just one poor example, old TEK 2225(more things can find in this older thread about 500uV/div scopes)futile and futile...try it with same price class Keysight, not even if you double or triple this price..but this can do in real life and there is many oscilloscopes in this price class or even higher what can not do even this. Of course accuracy, or is it better say inaccuracy, is what it is but still this give lot of more than nothing. Watching 3.3V supply rail level (this is why DC coupling and fixed vertical offset mode) and some details in it. 10x probe just because you said it.

author: tautech
author_rank: Super Contributor
timestamp: March 26, 2019, 08:21:20 am
content: Quote from: HalFET on March 26, 2019, 12:43:29 amOh, you are a one eyed SOB aren't you ?You remind me of many ppls in the 70's and 80's that would never buy a Jap car 'cause they're shit, right ?I was one of them back then but later my eyes opened, maybe there is still hope for you.From an 'A' brand 50 MHz DSO @ 2x price of SDS1104X-E:Bandwidth (–3 dB)1, 2.......................50-200 MHz modelsInput sensitivity range3500 μV/div to 10 V/divMaximum input voltage 150 Vrms, 200 VpkIn small print:1. Denotes warranted specifications........2. For 1 mV/div to 10 V/div settings,bandwidth is 20 MHz at the 500 μV/div setting.3. 500 μV/div is a magnification of 1 mV/div setting.The 100-200 MHz X-E's offer the full BW @ 500uV/divandit's not a magnification of some lower sensitivity range hence it shows more noise and therefore allows the operator to make decisions on best how to reduce displayed noise, not some designer hidden automatic BW limit that thinks it knows better than the competent user.Like farmers who know how to sift the wheat from the chaff, a good EE should know how to get the info they need from a dirty waveform.And what's with the Yanks, only 200Vpk inputs.Whereas X-E's in fact all Siglent DSO's are 400Vpk rated.Right, Siglent have no idea what they're doing........Right ?

author: Fungus
author_rank: Super Contributor
timestamp: March 26, 2019, 08:30:29 am
content: Quote from: tautech on March 26, 2019, 08:21:20 amWeird that you think 100% of Siglent owners are capable of this.(...and that 0% of Rigol owners are)

author: tautech
author_rank: Super Contributor
timestamp: March 26, 2019, 08:40:27 am
content: Quote from: Fungus on March 26, 2019, 08:30:29 amRefresher courses for you:https://youtu.be/Znwp0pK8TzkThen Pt 2:https://youtu.be/l5Cts5nPpcA

author: HalFET
author_rank: Frequent Contributor
timestamp: March 26, 2019, 10:09:41 am
content: You know, this would have been easier on both of us if you'd have shut up and known when to stop your sales pitch.Quote from: rf-loop on March 26, 2019, 07:46:11 amThat 9 MOhm resistance in the probe tip is suddenly non-existent for Siglent and only for Siglent? And it doesn't have a voltage noise in the microvolt range attached to it? Tell me more about these magical flux capacitor super conducting scope probe tips. And then I haven't started about the realistic lower limits for a 1 MOhm scope frontend.Quote from: rf-loop on March 26, 2019, 07:46:11 amKeysight will not advertise things they know they can't deliver on.Quote from: rf-loop on March 26, 2019, 07:46:11 amYou're going to use the Tektronix 2225 as example?So, before we continue this ridiculous use of a very specific scope as example, you are aware that the 2225 has a bandwidth of only 50 MHz which reduced to 5 MHz when you turned on the x10 amplifier? At least mention a semi-recent Keysight scope like your colleague did. Mind you, Keysight actually was smart enough to enable the bandwidth limiter for this "magnification".And it's not because the manufacturer puts "it can do <something>" on the box that it is either meaningful or true. Stop the damned sales pitch or at the very least admit you're associated with Siglent at this point, because it's quite obvious. All you have to do to sell scopes is say "look, we built something with a usable interface at this price point and it can do this", stop trying to add on features that don't actually work properly.but this can do in real life and there is many oscilloscopes in this price class or even higher what can not do even this. Of course accuracy, or is it better say inaccuracy, is what it is but still this give lot of more than nothing. Watching 3.3V supply rail level (this is why DC coupling and fixed vertical offset mode) and some details in it. 10x probe just because you said it.You do know this is quite meaningless right? That count at the side of the table betrays you, the scope is averaging measurements over multiple waveforms. If you had read the previous pages you'd have seen I posted screenshots of taking a DSO-X 2012A down to tens of microvolt of RMS voltage noise using exactly the same method. Possible, yes, practical, not really. So please, just stop it, this is getting ridiculous.Quote from: tautech on March 26, 2019, 08:21:20 amMy eyes are fine, but clearly you think that our analytical thinking skills are not. Rigol and Siglent can build decent scopes when they're manufacturing them for another manufacturer. Sadly they still have to realise that the market for engineering lab equipment tends to be aimed at engineers. So unlike consumer products, you're not going to sell them by lying out of your arse and hoping they only notice after purchase.Quote from: tautech on March 26, 2019, 08:21:20 amThank you for demonstrating my point for me, note the footnotes on the datasheet: Not only do they admit it's simply a multiplication of the 1 mV range, they also enable the bandwidth limiter. Because something magical happens when you calculatesqrt(4 k T R dF), do you see that "dF" factor in there? Thermal noise is a function of bandwidth... And guess what, if you calculate the thermal noise it seems to magically coincide with the noise voltage you get on a scope input, I wonder why that is?In other words, you'll find that the 500 µV/div mode on a keysight is slightly more useful than on the Siglent because they enable the bandwidth limiter for you, but you'll still need averaging or high-resolution mode to get anything useful out of it.So basically what you call "hiding from the user" is what competent engineers will call "understanding the physical limitations of our universe".Quote from: tautech on March 26, 2019, 08:21:20 amNot an excuse for lying on datasheets.Quote from: tautech on March 26, 2019, 08:21:20 amAaaaand, again with the lies. Most modern scopes are built identically for all markets through the magic of switch mode power supplies. So in practice that means most are rated for at least 240V RMS on the input (339Vpk). And all the semi-recent HPAKs sitting on my desk do 300Vrms (425Vpk). So what were you saying?All you're doing with this type of response is proving my initial point, just please be honest for once and actually say what the scopes can do instead of cherry picking results.

author: Fungus
author_rank: Super Contributor
timestamp: March 26, 2019, 10:18:08 am
content: Quote from: HalFET on March 26, 2019, 10:09:41 amAt least he's not hiding that part...

author: HalFET
author_rank: Frequent Contributor
timestamp: March 26, 2019, 10:23:48 am
content: Quote from: Fungus on March 26, 2019, 10:18:08 amYeah, I know. I was talking about rf-loops in that part though.

author: Fungus
author_rank: Super Contributor
timestamp: March 26, 2019, 10:28:04 am
content: Quote from: HalFET on March 26, 2019, 10:23:48 amOh, so you were.Yeah, I don't get rf-loop's angle. He seems to have enough knowledge to know that he's posting rubbish but he still does it anyway.

author: HalFET
author_rank: Frequent Contributor
timestamp: March 26, 2019, 10:33:42 am
content: Quote from: Fungus on March 26, 2019, 10:28:04 amI suspect Siglent pays them a fee per post. I'd understand in that case, heck if they pay enough I'll do it as well

author: rf-loop
author_rank: Super Contributor
timestamp: March 26, 2019, 11:37:22 am
content: Quote from: HalFET on March 26, 2019, 10:33:42 amIt is typical that after technical arguments or examples in in real life and so on ends then these AdHoc style starts.Booth of you, Rigol expert Fungus and Keysight's HalFET can show in practice with they scopes how they perform example with roughly same signal and setup in my last image Except that I understand why not... specially @Fungus because his oscilloscope is also in this thread topic. How it performs.@HalFETQuoteWhat is this doing under my image as some kind of "comment". I have seen your nonsense DSO-X images and they really have nothing to do with this. Here is captured signal. (Including tiny detail: measured rough DC level using offset DAC)If you do not really understand what all you see in image - well it is not my head ache. Btw, it looks that only what you have seen in image is this "count" and just this measurement table is perhaps most futile thing in the whole image.

author: Fungus
author_rank: Super Contributor
timestamp: March 26, 2019, 12:14:17 pm
content: Quote from: rf-loop on March 26, 2019, 11:37:22 amWhy should I even care?

author: ebastler
author_rank: Super Contributor
timestamp: March 26, 2019, 12:27:23 pm
content: Quote from: Fungus on March 26, 2019, 12:14:17 pmBecause you are happy to provide a service to the community here? If the only thing it does is to put an end to these "Rigol-vs-Siglent entry level scopes" debates once and for all, it would be abigservice to the community...

author: HalFET
author_rank: Frequent Contributor
timestamp: March 26, 2019, 12:58:52 pm
content: eblaster, this will never end, because they cherry pick their demonstration cases. For example, here he went for a 25 Ohm signal generator output with settings beyond what most signal generators can do. Furthermore he selected an offset voltage above 2V, because that's the limit that most manufacturers will allow as offset voltage for the mV ranges (though there are easy tricks around that one). Then he selected a 10 mV pulse, well knowing that many signal generators can't generate clean 100 ns pulses to begin with, so what you get is noisy by default. The images he showed is mostly a demonstration of how good his signal generator is, it doesn't actually show the performance of the scope. Of course, most electronics engineers are aware of these things, but that's not their intended market sadly.Quote from: rf-loop on March 26, 2019, 11:37:22 amWhich technical arguments? Highly selective screenshots? Do I really have to make a screenshot of a DSOX-2012A measuring a 500 MHz sinewave and then ask you to do the same with a 100 MHz bandwidth Siglent?Quote from: rf-loop on March 26, 2019, 11:37:22 amI work for Keysight now? Does this mean I got the keysight job I wanted anyway? That actually brings up a sad memory, I was contacted by a Keysight recruiter a few months ago, but due to the messed up way LinkedIn works she didn't see my response. So by the time she saw the position had already been filled.But that sad story aside, interesting how you don't deny working for or being associated with Siglent.And I love how you selected a challenge that is actually hard on the signal generator instead of the scope. Which signal generator did you use? Most common signal generators (i.e. a Rigol DG1022) can't do what you asked for, so by default it's hard to "disprove". I especially like the touch of lowering it to 25 Ohm impedance. As a result I did have to lower the offset voltage due to the limits of my desktop signal generator. But as you can see, a low-end DSO-X 2012A can trigger on such a signal and measure it. Used for this: an old Wavetek signal generator, DSO-X2012A with a N2862A 10:1 probe. Note that the noise is actually due to the inadequate nature of the signal generator for this job. If it was the noise from the scope averaging 8000 waveforms would remove it entirely. Are we now done with the silly mock measurements or is this going to continue?Quote from: rf-loop on March 26, 2019, 11:37:22 amSo you entirely deny that it says?Code:Sa 1.00 GSa/sCurr 65536 ptsdelta f = 15.26 kHzAVG = 4I'm fairly certain that "AVG" stands for averaging... Furthermore, claiming measurement accuracy is all fun and games, but if you don't understand why averaging over 567 periods is significant, do the math please. It significantly lowers the measurement error.And I am well aware the images I posted were ridiculous, that was very much the point of them. I essentially did the same you folks did, the only difference is that I showed what I was actually doing.

author: HalFET
author_rank: Frequent Contributor
timestamp: March 26, 2019, 01:05:16 pm
content: And just to add insult to injury, since the R&S SMH was running anyway, I hooked it up to the DSO-X 2012A to a 535 MHz sinewave. Please note that the oscilloscope's internal frequency reference is stable enough to match that of a signal generator driven of a GPS disciplined rubidium clock. Furthermore, it can measure a 5.8 mV signal at this frequency! Even the scope's internal DVM works at this frequency!

author: rf-loop
author_rank: Super Contributor
timestamp: March 26, 2019, 03:22:40 pm
content: Quote from: HalFET on March 26, 2019, 12:58:52 pmThere is so many things in your post what need comment but I will pick-up some with limited time.25 ohm. Are you really serious you wonder this? It is extremely common way example when we test probes.. for me it is very normal. Note that Signal was connected to scope using normal probe, not 50ohm transmission line."AVG #4" meaning in image..Time domain trace is NOT averaged at all. It is just normal realtime acquisition.FFTis averaged (#4)Why I select 3.3V offset in this previous image. Of course I select 3.3V offset because I want look (just as simulation for teaching purposes) 3.3V power rail and its details because there is "riding" something... what is not fully "unknown" anymore, least we have some trumpth (alternative truth) about it. There is around 10mV 100ns pulses.But then this visible noise, this is really undefined and I do not know but I believe least biggest part of it is from scope front end and rest. (of course I have looked it with same settings and probe without connection to anything but just same termination without connected to signal source)Offset can here be up to 20V. (perhaps you forget 1:10 probe when you wonder this)For 1:1 it is in Siglent+2V (500uV/div - 1180mV/div (most low voltage band)).If I look your image with over 500MHz sinewave. Naturally this Siglent model can not do it because max 1GSa/s.Some difference with Keysight. My eyes are very old and poor but even I can see difference...and also here Siglent time domain trace is without any averaging.../With Rigol, do not even try.For avoid next misunderstandings... attached again this same 3.3V DC with around 10mV 100ns pulses as previous but now without any extra on display and what can with Keysight detect in class... "there is something" if I look your images.-as previously, splitted window (time zoom) and without meas and FFT-no average, full screen-average #4, full screen-average 1024# (siglent maximum) full screen

author: Fungus
author_rank: Super Contributor
timestamp: March 26, 2019, 03:24:17 pm
content: Quote from: ebastler on March 26, 2019, 12:27:23 pmI've done it a dozen times. It's whack-a-mole, they just come back with something else......or even the same old crap. The infamous "Siglent vs. Rigol" spreadsheet isstillbeing reposted three years after it was debunked (seepage two of this thread).It's less relevant than ever because you don't even have to hack your Rigol to get all those "optional" features that are in there, they come as standard now. Doesn't stop it being reposted though.

author: Fungus
author_rank: Super Contributor
timestamp: March 26, 2019, 03:28:47 pm
content: Quote from: HalFET on March 26, 2019, 12:58:52 pmNo, no, no! These are "real life" examples!Quote from: rf-loop on March 26, 2019, 11:37:22 am

author: rf-loop
author_rank: Super Contributor
timestamp: March 26, 2019, 04:14:24 pm
content: Quote from: HalFET on March 26, 2019, 12:58:52 pmWhat are cherry pick.Example 25ohm source impedance is standard method for feed signal to probe. When do probe tests it is standard method. And even more, if I simulate for teaching purposes how to look example 3 or 5V rail for its voltage, slow drifting and impulses there... do you know what is then signal source impedance... buuh...Furhermore.Offset. There is 1:10 probe !!! and scope set for x10.3.3V is 330mV in scope input. What scope can not do this offset, even in mV range.If setting is x1 then example Siglent have +/- 2V limit. 2v x 10 is 20V. This math works also in Siglent... buuh..Why 10mV signal... just because I want walk around Rigol when it run. (and because this kind of ripple in 3.3V rail under test is not rare at all."Then he selected a 10 mV pulse, well knowing that many signal generators can't generate clean 100 ns pulses to begin with, so what you get is noisy by default."Also 100ns pulse width is not at all unusual miracle, things what we meet in real life with many DUT's frequently. And if can not do pulse 200ns period 50% duty rectangle (square). 5MHz square.. buuh... oh but then... 2MHz square but 20% duty...buuh..."noisy by default"... I think here scope front end noise is dominating clearly.And if want low level from cheap generators like example Rigol DG1022. Drive out higher level and use normal external attenuator if you afraid its bottom level noise. Normal practice for low level signals.This demonstration was made using cheap Siglent SDG1032X using just some BNC T, probe adapter feed thru's (for terminate it). Not even external attenuator. This is not how expensive equipments we have, it is how we use them. Example for detect well below 100nm anomalies in telescope main mirror shape need just one candle and razor blade.

author: TurboTom
author_rank: Super Contributor
timestamp: March 26, 2019, 05:16:32 pm
content: Quote from: rf-loop on March 26, 2019, 03:22:40 pm@rf-loop: You've got to be careful with statements that you haven't proven yourself (btw, I had to learn this as well by experience) and admittedly, it's not as beautiful as with the more modern Siglent, but the result with a DS1054Z (liberated) is probably far better than some may expect. The FFT is crap and we don't need to discuss this (though depending on the settings, it's possible to get moch better results, especially with higher timebase settings) and it isn't possible to display the original waveform, a zoomed one and the FFT at the same time. I forgot to enable the bandwidth limiter but it would have little, though just noticable, effect on the noise. High res also wouldn't help much to reduce the noise (maybe by 40%) which still results in rather high Vpp measurement. But with averaging (notice, only 16 scans used), the signal looks really nice and the measurements are quite good.To feed the signal to the scope, I used low a 50 ohms 20db attenuator and fed it directly by a signal generator with 10mVpp/ 3.3V offset. Probe attenuation was set to 1:1 so the scope will report the signal that (it "believes") is directly present at its input.Actually, I wouldn't have thought that the old "Zed" performs so respectably. Definitely anything else than useless.Maybe this can take out a little the "sharpness" from the "Scope Wars"...Cheers,Tom

author: HalFET
author_rank: Frequent Contributor
timestamp: March 26, 2019, 06:33:23 pm
content: Quote from: Fungus on March 26, 2019, 03:24:17 pmNot to mention pointing out his coincidences seems to hit quite the nerve. The worst part is that these guys never stop, they always come up with something that's just slightly different.I'm honestly not going to bother citing specific parts of his post anymore, I suspect this covers all of it:a) You claim you need to terminate it with 50 Ohm because you're measuring an RF output, what you're actually doing is generating optimal conditions for your signal generator and scope instead of just slapping it in high impedance mode like any sane person would for this measurement.b) Your measurement does not add up, the noise ought to be higher with a x10 probe if it's not averaging in some way, or J.B. Johnson was wrong. (That's also an option I suppose?) It should look more like Tom's screenshot. Hence, I suspect you did not use a probe which is why 2V is the realistic limit.c) You always resort to fancy display modes to hide the actual signal.d) I suspect you used a secondary output of the signal generator to generate a stable external trigger signal to the scope.e) The entire point of that 535 MHz measurement is showing you how ridiculous these screenshots are as proof, it's so easy to doctor these things that it ain't even funny. Want to know how I did it? A Rohde & Schwarz SMH will happily dump 13 dBm into any load you present to it. So sure, you lose about 99% of your signal in the frontend at >400 MHz, nor do the input controls still have much effect on which signal is actually coming through, but hey it's a signal coming through to the ADC. At the same time I also used a second signal derived from the same reference as the signal generator uses to trigger the scope reliably at this rate. Next I turned on the DVM feature of the scope to hide the acquisition details so you couldn't see I had it on averaging mode, etc. Now I could have claimed the scope could repeatably see a 535 MHz sine with a 10 mV peak-peak and 5 mV offset you'd have been non the wiser. What actually happened is that I applied the same set of tricks as were most likely used to make these screenshots.@TurboTom, thanks for showing what it looks like without messing around!

author: ebastler
author_rank: Super Contributor
timestamp: March 26, 2019, 07:21:28 pm
content: Quote from: rf-loop on March 26, 2019, 07:46:11 am@rf_loop, two quick questions, to make sure I understand those results:- The yellow "B DC1M" label on the right, I assume it means that a 1MHz bandpass filter is enabled? Nice to have that on the scope, but has its use ever been mentioned in this comparison? Or do I misunderstand?- The data table suggests a StdDev of 3.9 mV, i.e. the +- StdDev trace should be quite a bit wider than one vertical division. That's not at all what it looks like visually. I assume this is due to the funky false-color scale you applied to the signal?EDIT: Ahh, hang on. The StdDev includes the variation due to the 2 MHz signal, of course. But nevertheless:Could you repeat this demo with a regular trace color please?Thanks!Jürgen

author: 0culus
author_rank: Super Contributor
timestamp: March 26, 2019, 07:35:32 pm
content: Quote from: HalFET on March 26, 2019, 06:33:23 pmExactly my thoughts as I was reading through this thread. "If it's too good to be true, then it probably is"...it's kind of hilarious to watch the marketing wank in this thread.

author: 2N3055
author_rank: Super Contributor
timestamp: March 26, 2019, 08:02:28 pm
content: DC1M means DC coupling and 1Meg input impedance. There is no 1MHz filter on that scope.Also SDEV is AC RMS of that square wave signal.SDEV of statistics is right most column. And it shows pretty low distribution across previously acquired screens.And what's up with all the hate and accusations ? Cherry picking measurements that make someone look good is not even close to accusing someone to be outright lying and cheating with results.I don't see nothing wrong with RF-Loop captures. SD 1000X-E does have 10X amplification in the front end and real analog 500uV/DIV front end.It has to have lower noise than Rigol or Keysight that has maximum analog sensitivity of 5mV/DIV.I find rf-loop to be abrasive at moments, but fact that he is not trying to be likable doesn't make him a liar...At least unless someone with same Siglent proves that they cannot repeat the result..Just a bit more civility will make this argument more what it needs to be.. A discussion about technical merits of some measurement equipment.Regards,

author: ebastler
author_rank: Super Contributor
timestamp: March 26, 2019, 08:09:49 pm
content: Quote from: 2N3055 on March 26, 2019, 08:02:28 pmDuh...QuoteRight; and at least that one I did figure out myself.See the recent edit above.I assume your further comments were directed at other posters; I have no beef with rf-loop.

author: 2N3055
author_rank: Super Contributor
timestamp: March 26, 2019, 08:49:04 pm
content: Quote from: ebastler on March 26, 2019, 08:09:49 pmNO not at you.. By no means, I apologize for not being clear..Regards..

author: rf-loop
author_rank: Super Contributor
timestamp: March 26, 2019, 08:55:27 pm
content: Quote from: ebastler on March 26, 2019, 07:21:28 pmB DC1M in channel 1 label:B= band width and in this scope front end BW is 20MHz 1st order like low pass.DC= coupling DC1M input impedance 1M.Also as can see it can not be 1MHz filter, as can see pulse width is 100ns, it have also some risetime and repeating frequency is 2MHz.--------@TurboTom, thank you, this was nice. It also rise question in my mind - is it possible Rigol have somehow changed hardware after I have owned DS1kZ >4 years ago. If I think what I have seen in my own tests, this your result is unexpected to me even when I think you have used it in this tests with all your (known) skills.

author: Fungus
author_rank: Super Contributor
timestamp: March 26, 2019, 09:19:18 pm
content: Quote from: rf-loop on March 26, 2019, 08:55:27 pmThe FFT had a big software upgrade a couple of years ago.The original DS1054Z did the FFT from on-screen data so it only had 1200 points. The results were predictably awful, this is theDS1054Z FFT seen in Dave's FFT shootout video.Since then they changed it to do FFT from sample memory (64k points of data IIRC). It's much better now.

author: rf-loop
author_rank: Super Contributor
timestamp: March 26, 2019, 09:37:04 pm
content: Quote from: HalFET on March 26, 2019, 06:33:23 pmI do not know for what (or who) are these comments..a) in my test there was 1:10 prope (Siglent PB215) connected diredctly to oscilloscope 1Mohm 15pF input BNC.b) I have told where is averaging and where not, excactly.But then.. about Johnson. What about Johnson... when you calculate from schoolbook direrctly example some resistor noise... well it is (propably) right. But do not stop thinking, you need think also it inside system and how it affect there under loading. I give some tips. Think this noise generation impedance. Ok, think this "generator" with its "source" impedance and what kind of also reactive load there is in circuit..c) what "fancy" display mode what hide something..d) Trigger source and type can see in every image.. in my images in this topic, signal in channel 1 and same signal exactly is also trigger source (and even more, trigger circuit is seeing same signal (not like conventional analog side pathway trigger system) because it have true digital side trigger engine what use same data after ADC what is also source for signal display. And same in Rigol.There is only one signal pathway from input BNC to ADC and then this digitized signal for display and trigger system, principle is explained in R&S RTO information. Same principle but of course not in same performance level.

author: nctnico
author_rank: Super Contributor
timestamp: March 26, 2019, 10:23:03 pm
content: Quote from: Fungus on March 26, 2019, 09:19:18 pmBut that still doesn't mean the DS1054Z isn't very outdated. Nowadays you can buy a much better scope for the same amount of money (give or take some fluctuations between distributors).

author: TurboTom
author_rank: Super Contributor
timestamp: March 26, 2019, 11:21:53 pm
content: Quote from: Fungus on March 26, 2019, 09:19:18 pmThat's true. Actually, currently the "Zed" provides the best FFT performance of the "old" Rigol scope series. Anyway, @nctnico is also right that the scopes of this series are more or less outdated and someone getting into electronics, shopping for a first scope shouldn't consider any of these anymore, except maybe for the price (if there's a really good opportunity waving...). Yet, I still like the "Zed" a lot for its very compact form factor (it's my "push-around-scope" and there's notoriously too little free real estate available on my workbenches...And it's mechanically very well built, quite rigid and beefy. I'm not sure if the more modern alternatives are as durable as this one.Just for fun, I shoved a 30cm wire into a 50Ohms-feed-through terminator and plugged that into the "Zed" to play around with its FFT. It's really amazing how well the closer FM radio stations can be resolved if the FFT is configured properly. For comparison, I added the same frequency range with the same "source" as a screenshot from an SA. The SA is purposely configured to display the levels in dBmV so the comparison with the scope is easier (dBV -- add 60 to convert dBV to dBmV). It's quite amazing how well the figures match.Whatsoever, this doesn't change the known facts but it shows that despite all the (sometimes legitimate) Rigol bashing, they continouosly kept on improving their product and I'm sure the "Zed" will stay a reliable tool for its owners with average demands for years to come.Cheers,Thomas

author: tautech
author_rank: Super Contributor
timestamp: March 27, 2019, 07:07:30 am
content: Quote from: HalFET on March 26, 2019, 01:05:16 pmQuote from: HalFET on March 26, 2019, 06:33:23 pmYes well not too flash trace there for an A brand DSO.No tricks 520 MHz sine wave ex HP8654BNo hidden settings, no fancy triggering, just plug and play on a $600 X-E DSO.

author: ebastler
author_rank: Super Contributor
timestamp: March 27, 2019, 07:15:30 am
content: Quote from: tautech on March 27, 2019, 07:07:30 amHmm... I believe I can spot a tiny difference in masurement conditions there, v.s. HalFET's example? Signal amplitude, maybe?Anyway, I think I'll unsubscribe from this thread now.These pissing contests get boring over time.

author: 0culus
author_rank: Super Contributor
timestamp: March 27, 2019, 07:27:59 am
content: Quote from: tautech on March 27, 2019, 07:07:30 amYour scope appears to be set up completely differently than his, so any conclusions drawn from that are pure wank from where I'm sitting. Your vertical scale is unknown from the screenshot, and I'd guess you're using a coax directly into a 50termination whereas he is using a 10x probe it looks like.Ultimately, what does it matter though? The Chinese OEMs make decent instruments that certainly give those on a tight budget the ability to buy a great deal of NEW scope for their money. That's a positive thing for the electronics hobby since not everyone also wants to collect boat anchors (I'm fine with that...more boat anchors for me) However, I seriously doubt that Siglent/Rigol/whoever have discovered some sort of unobtainium that magically makes a $600 scope better than a $6000 scope. I just pulled those numbers out of my arse but the point stands.

author: Fungus
author_rank: Super Contributor
timestamp: March 27, 2019, 10:51:50 am
content: Quote from: tautech on March 27, 2019, 07:07:30 amSure, but with what cables and (most important) what was theoriginalamplitude of the wave?FWIW: The Rigol DS1054Z still shows nice sine waves over 300Mhz and the "70MHz" Rigol MSO5072 can show 1GHz signals after hacking. That doesn't make them 300Mhz/1GHz oscilloscopes.

author: nctnico
author_rank: Super Contributor
timestamp: March 27, 2019, 12:23:54 pm
content: Agreed. It makes no sense to look at signals far beyond the bandwidth of an oscilloscope since you have no idea about the actual amplitude. The phase shift is probably horrible as well.

author: Fungus
author_rank: Super Contributor
timestamp: March 27, 2019, 12:37:17 pm
content: Quote from: TurboTom on March 26, 2019, 11:21:53 pmPrice is often very important.Is there an alternative four-channel 'scope for 350 bucks that's "modern"?Quote from: TurboTom on March 26, 2019, 11:21:53 pmYep. Anybody expecting a Rigol to feel cheap and plasticky is in for a big surprise, they're built like brick outhouses.A lot of the weight is in the full metal chassis underneath but the outer case is no lightweight.

author: tautech
author_rank: Super Contributor
timestamp: March 27, 2019, 12:46:10 pm
content: Quote from: Fungus on March 27, 2019, 10:51:50 am1 GHz rated Siglent BNC cable and p-p ~1V (~13dB) input.QuoteAgreed 100 %For those that missed it and they might indeed need Specsavers, HalFET bought a 2 GSa/s DSO into a 1 GSa's DSO discussion toproveentry level DSO's are shite.He had to resort to underhand tricks to have it trigger on a 500 MHz signal of the easiest type to trigger on and then further reduce the amplitude using 10x probes and low V/div settings hoping no one would notice the poor waveform reproduction raster.So as I don't have a 100 MHz 2 GSa/s DSO a 200 MHz one was used instead for some fairer apples vs apples comparison.No hidden sampling rate or memory depth, just exactly as factory default with rock solid triggering and display.Shall we return to normal programming comparingsimilar1 GSa/s DSO's ?

author: Fungus
author_rank: Super Contributor
timestamp: March 27, 2019, 12:51:31 pm
content: Quote from: tautech on March 27, 2019, 12:46:10 pmSure, right after you admit the original amplitude of that signal.

author: tautech
author_rank: Super Contributor
timestamp: March 27, 2019, 12:52:34 pm
content: Quote from: Fungus on March 27, 2019, 12:51:31 pmOK, you need to go to Specsavers too.

author: Fungus
author_rank: Super Contributor
timestamp: March 27, 2019, 01:02:01 pm
content: OK, I found it.Original signal 1V, displayed signal 250mV (approx).

author: nctnico
author_rank: Super Contributor
timestamp: March 27, 2019, 01:54:41 pm
content: Quote from: Fungus on March 27, 2019, 12:37:17 pmYou know very well there is: the GW Instek GDS1054B. Uphackable to 200MHz, decoding, 10Mpts per channel, 1Mpts FFT, signal filtering, etc. It is better compared to the DS1054Z in every sense. The GDS1054B even has individual channel controls. At Tequipment the price difference is like 15 dollar.

author: Fungus
author_rank: Super Contributor
timestamp: March 27, 2019, 03:29:28 pm
content: Quote from: nctnico on March 27, 2019, 01:54:41 pmKey word: "Modern"The GDS1054B is as antique as the DS1054Z.

author: Fungus
author_rank: Super Contributor
timestamp: March 27, 2019, 05:24:30 pm
content: Quote from: nctnico on March 27, 2019, 01:54:41 pmI'm not 100% up to date but with all the recent hacks and addons (eg. decoding) it seems to be going up in value.Maybe time to persuade Dave to do a video about hacking the one in his lab. It might finish off the DS1054Zandthe Siglent.(still ugly though)

author: nctnico
author_rank: Super Contributor
timestamp: March 27, 2019, 05:37:44 pm
content: Quote from: Fungus on March 27, 2019, 03:29:28 pmDon't be an idiot. The GDS1054B is based on the Xilinx Zync just like every modern low-end and mid-range DSO out there.

author: ebastler
author_rank: Super Contributor
timestamp: March 27, 2019, 05:39:53 pm
content: Isn't it reassuring that most people here seem to be quite happy with the scopes they got, and defend their respective strengths rather than complaining about their weaknesses? Whether it's Rigol, Siglent, GW-Instek or Keysight, everybody who posted here seems to feel that they made the right decision buying theirs. (Well, Siglent may be a slight exception -- for whatever reason, we don't seem to have a vocal Siglent buyer in the forum, but two competent sellers or former sellers.)I am no different, to be honest: Bought my DS1054Zthreefour*years ago, and while I realize that there may be better scopes for only slightly more money today, I am happy with what I have. I like the compact form factor, build quality and screen layout (don't care much about the front panel layout though); the measurement capabilities have never been limiting for me; the tardy response of the traces to e.g. vertical offset adjustments can be a nuisance.Would I buy it again today? I would actually need to compare with the other offers in a hands-on test, which I never had the opportunity to do. The things I like least and best about the DS1054Z are all look-and-feel related, rather than based on datasheet specs. So I honestly don't know.*Edit: Time flies...

author: tv84
author_rank: Super Contributor
timestamp: March 27, 2019, 05:59:32 pm
content: @nctnico, be carefull because you can be accused of OT... Let's see if it will happen...

author: KlausF
author_rank: Contributor
timestamp: March 27, 2019, 06:06:05 pm
content: If you ask me, I would also reccommend a GwInstek. Serial bus decoding and segmented history are included.

author: smarteebit
author_rank: Contributor
timestamp: March 28, 2019, 01:53:33 am
content: I would expect more real opinions from the end users instead of a few re-sellers fighting here.

author: bitseeker
author_rank: Super Contributor
timestamp: March 28, 2019, 05:30:20 am
content: Quote from: nctnico on March 27, 2019, 01:54:41 pmWow, I didn't know the price of the GDS1054B had come down that much. If it had been released earlier and been a similar price as the DS1054Z, I probably would've gone with the GW Instek (how could you turn down individual channel controls?). On the other hand, at least I had fewer things to decide amongst.

author: nctnico
author_rank: Super Contributor
timestamp: March 28, 2019, 06:46:31 am
content: Quote from: bitseeker on March 28, 2019, 05:30:20 amActually the price of the GDS1054B has always been on par with the DS1054Z. Only the former wasn't hackable until recently.

author: Fungus
author_rank: Super Contributor
timestamp: March 28, 2019, 06:51:51 am
content: Quote from: nctnico on March 28, 2019, 06:46:31 amYep. The historical problem was that it wasn't hackable, it had no serial decoders, etc. As a 50MHz device with few features it didn't compete.haven't been following the details but in the last six months it seems to have been hacked to 200MHz and a load of extra features added to it through hacking. It seems to use a plugin architecture and people have figured out how to make plugins.

author: ebastler
author_rank: Super Contributor
timestamp: March 28, 2019, 07:06:35 am
content: Quote from: smarteebit on March 28, 2019, 01:53:33 amTautech is, and rf-loop (I believe) was a re-seller for Siglent. Everybody else here is an end user without affiliation with any manufacturer, to my knowledge. If anybody does have a vested interest in any of the brands (beyond pride of ownership ;-), it would be the right thing to disclose that here.

author: BillB
author_rank: Unknown
timestamp: March 28, 2019, 01:30:14 pm
content: Quote from: ebastler on March 28, 2019, 07:06:35 amI'll chime-in as a Siglent brand user as well. Being primarily exposed to/and having history with the A brands through my work, I had followed the lesser brand market with curiosity for a long time. I really hadn't taken them seriously nor spent much time considering them, however, seeing that many were moving to an embedded Linux architecture changed my mind.I decided to outfit a "mini-lab" at home to investigate what some of these devices could offer and to see how they competed. I researched most of the brands discussed, and partially based on features/price/availability and partially just arbitrarily I chose to buy a suite of Siglent products. Frankly, for the price I was shocked at how much functionality they offered. While they weren't quite as polished as the A brands, and have some quirks/bugs, the response from all the technical support resources (here online as well as the US distributor) has been timely and appropriate.I suspect that most users like myself in this market probably followed a similar path and have much more experience with one B brand than the others, so I can't make direct comparisons. What I can say is that I have not been disappointed in the equipment I selected. In fact, I've even purchased more units for my work office where I don't need critical top-of-the-line performance/accuracy/etc, but just need something that works and doesn't disappear from my desk.I'll also add that the people on this forum, including tautech and rf-loop, have been extremely helpful and responsive and are a great resource no matter which brand you choose.

author: Fungus
author_rank: Super Contributor
timestamp: March 28, 2019, 02:51:49 pm
content: Quote from: BillB on March 28, 2019, 01:30:14 pmReading between the lines, a lot of your positive impression seems to be based on the support network. It's worth noting that most non-business users (ie. the target for these cheap 'scopes) who buy a single unit simply won't get any of that.

author: tv84
author_rank: Super Contributor
timestamp: March 28, 2019, 03:11:35 pm
content: Quote from: ebastler on March 28, 2019, 07:06:35 amFrom my distant PoV, I see many "non-affiliated" users here that are way more fanatic that the supposed/identified "affiliated" ones!Affiliated usersusuallyhave a degree of responsibility far greater that the other ones because of their professional relationship.People have the obligation to weight carefully the opinions of sales persons. People don't have to trust everything they say AND they also shouldn't be attacked just by being in the position they are.It worries me much more the level of "fan-club fanaticism" that some members demonstrate. Many of you demonstrate a great level of knowledge, most of times are saying precisely the same thing in different conditions BUT, just because you are talking of the "opposition's model", then you must bash the other one's argument just to keep this in the "eternal question" realm!What a waste of good resources!

author: BillB
author_rank: Unknown
timestamp: March 28, 2019, 06:12:05 pm
content: Quote from: Fungus on March 28, 2019, 02:51:49 pmYou are right. I have had positive experiences with Siglent's support network, but I don't understand why a hobbyist wouldn't get the same support I did? For example, I had a dud SDG1032X AWG at home that failed after a short time and I sent it to Siglent US and they repaired it and turned it around in short order. I wasn't happy about getting a dud in the first place, in fact, I was quite nervous at that point thinking I had made a big mistake purchasing the suite of products.However, that is the only issue I have had with any of their equipment and the 3 year warranty is a nice peace of mind. Though, I could understand that distributors in other countries might not be as helpful as here in the States. Most all of the other support I received has come from this forum, include tautech, whose help is available to anyone here.

author: rsjsouza
author_rank: Super Contributor
timestamp: March 28, 2019, 06:25:40 pm
content: Quote from: tv84 on March 28, 2019, 03:11:35 pmAnd, as usually is the case, the original beginner poster ran awaywith the whole brouhaha he unintentionally sparked.

author: Gregi
author_rank: Contributor
timestamp: April 10, 2019, 08:26:19 pm
content: hey hey, I have been away for a while and now i have red all the comments you guys wrote. My decision is that I will wait for a couple of months to purchase a scope becouse I decided to make a new workshop firstbut I am really considering about buying sigilent one....thank you all for the advices

author: tv84
author_rank: Super Contributor
timestamp: April 10, 2019, 10:33:46 pm
content: Don't forget to relaunch the question once the workshop is finished!

author: Old Printer
author_rank: Frequent Contributor
timestamp: April 11, 2019, 03:15:30 am
content: I have always been a bit naive, so may be doing it again. Tautech has helped a lot of people with countless scope/awg questions and problems. most Siglent based, but not all. He has done in depth research to offer solutions to various problems, which sometimes takes days and several posts. He is openly the New Zealand distributor for Siglent, so helping a guy from Romania or the states is unlikely to foster a sale for him. Maybe Siglent pays him by the post, I don't know, but I see no one in a similar position for either Rigol or GWS doing anything remotely as useful. Maybe my naivety prevents me from seeing the actual goings on, I don't know.

author: ebastler
author_rank: Super Contributor
timestamp: April 11, 2019, 05:51:40 am
content: Quote from: Old Printer on April 11, 2019, 03:15:30 amWell, Tautech obviously has a (financial) interest in making sure that Siglent products are seen in a positive light on this forum. That will affect purchasing decisions in New Zealand, among many others, and hence some of the benefit will come his way.That being said, there's no doubt that Tautech is both highly knowledgeable and very helpful! It is no coincidence that he is among the top three in the forum's "number of thanked posts" ranking.Tautech's advice is always solid, and has brought quite a few new insights for me. But it is also true that he tends to stress the strengths of Siglent products, and I have rarely seen him point out their limitations or weaknesses. (Understandably so.) That's what I meant when, several posts ago, I mentioned that we had "only" users speak about Rigol and GW-Instek, while the two Siglent advocates/experts have a different background.

author: Fungus
author_rank: Super Contributor
timestamp: April 11, 2019, 07:26:15 am
content: Quote from: ebastler on April 11, 2019, 05:51:40 amYep. It makes no difference where forum readers live.Quote from: ebastler on April 11, 2019, 05:51:40 amAgree.Quote from: ebastler on April 11, 2019, 05:51:40 amYep. Reading pro-Siglent posts here you'll get the impression that they're all rainbows and unicorns which simply isn't true.You might also get the impression that the Rigol DS1054Z is rubbish. That simply isn't true either, it has a lot of very good things in its favor. The problem is that every single thread that mentions one turns into a flame-fest with Rigol owners appearing to be on the "defensive".The simple fact is that these two scopesdon't cost the same amount of money. If we were comparing a Ford Fiesta and a Ford Focus then everybody would be so busy pointing that out that any other argument would be moot. If the argument is that we should "always buy the best tool possible" then why stop at Siglent/Ford Focus? Why not save up for a Rolls Royce (or look for a second hand one)?Question: Would you really feel the difference between a Ford Focus and a Ford Fiesta on the daily commute? Both have air-con, about the same amount of leg room and optional leather seats. Both can do the weekly shop, too.TLDR version; Siglent'saren'tFerraris.

author: RFDUK
author_rank: Regular Contributor
timestamp: April 11, 2019, 08:23:12 am
content: Some experience I would like to add about brand promotion on the forum from 'distributors' ...Late 2017, early 2018 Siglent had a production issue with their SSA spectrum analyser. Work on this forum helped resolve this.I received a 'faulty' instrument, returned it. 2nd instrument had the same fault but worse. I concluded Siglent had a problem and let the supplier (Batronix) know the technical details to tell the factory.I did a fair bit of research along with other owners on this forum to at least fully describe and understand the nature of the issue. The forum at large was spectacularly helpful in doing this and I've no doubt many on lookers learned new stuff along the way too. All good.Longer wait this time and eventually Siglent found their issue and delivered a 3rd instrument well inside spec. They had found and corrected the problem.Now to the point. A Siglent distributor input to the thread at the time was particularly unhelpful and patronising:Example Post 1 … 'We can go witch hunting spurs all year'Then later realising this problem was 'real' ...Example Post 2 … 'All readers can be very sure Siglent are informed of this matter and are working on and watching developments.They have indicated that they will inform ‘us’ (means DISTRIBUTORS) of their findings, in what detail and when, only time will tell.It is my view to leave them to fully investigate why spurs do not meet spec and not press them for fast and short answers'This is nothing but a blatant effort to close down discussion?At the time I seriously doubted my decision to buy Siglent if this was the quality of the field support. Once I'd calmed down I realised I should just concentrate on my comms with Batronix and consequently found Siglent very helpful in resolving the issue through that channel.Truth is the work done on the forum was extremely helpful to Siglent, without it they would probably have shipped many more out of spec instruments.Forum 'likes' are often placed by sincere folks in praise of help given. Lots of posts can mean lots of likes. However in isolation they obviously don't necessarily reflect the quality of the advice given?A year on the Siglent instrument has worked flawlessly and in hindsight provides much more for the price than the nearest competitor.

author: Fungus
author_rank: Super Contributor
timestamp: April 11, 2019, 09:25:01 am
content: Quote from: RFDUK on April 11, 2019, 08:23:12 amYep, and now if you head over to the "Should I buy a Rigol MSO5000 thread" you'll findthe Siglent boys people telling you to not buy a Rigol because it's completely unusable because of all the bugs, that the bugs will take many years to fix, that Rigol is a garbage manufacturer, etc.Meanwhilethe Rigol owners simply aren't seeing those problems.Who are we going to believe?

author: tautech
author_rank: Super Contributor
timestamp: April 11, 2019, 09:34:11 am
content: Quote from: Fungus on April 11, 2019, 09:25:01 amWell not you as you have some facts totally wrong !Your 'Siglent boy' is not currently a Siglent DSO owner and in fact is a strong critic of Siglent DSO's !Fungus, again you have failed to do your homework !

author: Fungus
author_rank: Super Contributor
timestamp: April 11, 2019, 10:43:31 am
content: Quote from: tautech on April 11, 2019, 09:34:11 amOK, I get 0/10 for quoting, but the main point still stands.

author: tv84
author_rank: Super Contributor
timestamp: April 11, 2019, 01:34:22 pm
content: Quote from: ebastler on April 11, 2019, 05:51:40 amIf it was any other way, I would find it extremely strange!!But another important thing that is worth mentioning:Tautech is always available to forward any bugs/problems to Siglent, from anyone!Unfortunately I don't see any of the "Rigol boys" do that for Rigol! That would be a great service to the forum.

author: ebastler
author_rank: Super Contributor
timestamp: April 11, 2019, 01:40:26 pm
content: Quote from: tv84 on April 11, 2019, 01:34:22 pmThe Rigol users on the forum are just that -- users and customers of Rigol. They know the same public email addresses and web pages as you do. What do you expect??

author: tv84
author_rank: Super Contributor
timestamp: April 11, 2019, 01:50:57 pm
content: Some seem sponsored...

author: BillB
author_rank: Unknown
timestamp: April 11, 2019, 06:19:50 pm
content: Quote from: ebastler on April 11, 2019, 05:51:40 amFrom what I recall, tautech has a less-than-ebullient appreciation for the SLA1016 logic probe that can be purchased for the SDS*X-E scopes. I almost felt as if he was trying to talk me out of getting one. I bought one anyway, and I might even buy another.

author: Gregi
author_rank: Contributor
timestamp: April 11, 2019, 09:31:37 pm
content: Quote from: Old Printer on April 11, 2019, 03:15:30 amI wont mate;)

author: tautech
author_rank: Super Contributor
timestamp: April 11, 2019, 10:25:18 pm
content: Quote from: Old Printer on April 11, 2019, 03:15:30 amIt helps that I have a range of demo models that I can replicate issues with and/or offer advice usage.QuoteI don't get one red cent from Siglent for my efforts here other than the feedback from you guys to pass to Siglent whether it be good or bad which then enhances product quality and functionality and then we all benefit.They send me a small Christmas prezzie (and last year one for Defpom too) as some token of thanks for our efforts.Other gratitude's received was a nice lunch when I visited the factory some 5 years ago and more recently a free pre-production DSO to beta test.The massive pool of experience here has helped Siglent improve all their products which of course translates into better marketplace acceptance and increased worldwide sales that I might also share in.Going forward, I too am learning each time new products are released and try to hold at least a demo model of new products so to have some familiarity with them for local and EEVblog support.Unless there are language issues I try to do all this here on EEVblog so others that strike the same issues can learn from it too. Support to EEVblog members via PM is NOT my style.I should add that the complexity of modern equipment can be a hurdle even for those with some experience and what may seem like a bug is often a usage error. However please keep posting about things that aren't understood as there's always someone ready to help within a short time.To those that may have not had the help they expected or hoped for, well I am human and can make mistakes.

author: 0culus
author_rank: Super Contributor
timestamp: April 11, 2019, 10:27:26 pm
content: I guess some people are brittle, but you clearly identify who you represent and you are super helpful. I'd rather have that than a curmudgeon who is hiding associations with vendors.

author: tautech
author_rank: Super Contributor
timestamp: April 11, 2019, 10:44:39 pm
content: Quote from: 0culus on April 11, 2019, 10:27:26 pmAgreed however as a member one can access all the posts of anyone else here and in doing that it can be plainly clear any bias or affiliation they might have.Like when buying equipment, we do our homework, right ?Do the same with any member.I've read on numerous times some 1000's of posts by a member to gain better understanding of their knowledge and experience. It can be very revealing and any of these might apply:and so on.

author: StillTrying
author_rank: Super Contributor
timestamp: April 11, 2019, 11:51:53 pm
content: Siglent + CML+ = A mystery to me.Am I the only 1 in the whole world that sometimes uses Dots, Persistence, ExtTrig, STOP, ScanMode, Invert, or ETS(LOL).Who's idea was it to have 1 channel bright yellow and the other dark purple - which has to have a different coloured persistence.

author: tautech
author_rank: Super Contributor
timestamp: April 12, 2019, 12:00:24 am
content: Quote from: StillTrying on April 11, 2019, 11:51:53 pmYes I know, currently I'm havinganotherbitch about these ^ !

author: StillTrying
author_rank: Super Contributor
timestamp: April 12, 2019, 01:11:31 am
content: Quote from: tautech on April 12, 2019, 12:00:24 amI really don't get it,arewere there any other reports of some of thesefeatures, I use Dots about 25% of the time and the simple Persistence about 90% of the time, I must be the only one.The only thing I've noticed with .20 so far is self-cal has reduced CH2's 2mV/Div. GND-0V 0.2 Div error to just 0.1Div. which is fine, - it's the first time I've noticed anything change after a self-cal.

author: tautech
author_rank: Super Contributor
timestamp: April 12, 2019, 02:03:47 am
content: Quote from: StillTrying on April 12, 2019, 01:11:31 amDunno and it doesn't matter as your work was plenty good enough for them to follow and then rectify what you'd bought to our attention.Maybe they only sell these to the edu marketplace and they are not being used to their potential as you do.Pisses me off some that CML+ is not as good as CML was.