12 bit Keysight... when? - Page 1
Forum section: electronics / testgear

author: jashugan
author_rank: Regular Contributor
timestamp: December 22, 2023, 10:59:07 am
content: Hello,I see now almost every manufacturer has its line of 12 bit oscilloscope: Lecroy, Tektronix, Rigol, Siglent, R&S... But what about Keysight? Any news about a new oscilloscope from Keysight? I own a wonderful DSOX3054T, and I'm enthusiastic about it, but I'd like to have 12 bit (and a lot more memory).

author: H.O
author_rank: Frequent Contributor
timestamp: December 22, 2023, 11:07:37 am
content: Keysight products are - as they say themselves - 'intended for professional and industrial use only'.I guess Keysight thinks that professionals can do with 8bits what everybody else needs 12 for...

author: coromonadalix
author_rank: Super Contributor
timestamp: December 22, 2023, 12:52:34 pm
content: Forget Keysight

author: jashugan
author_rank: Regular Contributor
timestamp: December 22, 2023, 02:44:55 pm
content: Quote from: coromonadalix on December 22, 2023, 12:52:34 pmWhy?

author: Sighound36
author_rank: Frequent Contributor
timestamp: December 22, 2023, 03:13:29 pm
content: When it does happen it will rushed through as the bean counters will wish for instant payback on their skimped investiment, it will BIG, loud and take forever to boot up. Think of the wannebe muscle car mentality form the 70's. Think a 12 bit version of the the MXR, wonder where that went?Plus we will get a Danny Bogdanoff 2 month lead on with video teasers on how good the the testing in the envirnomental chamber will be on this new scope.Thing is currently they are dumping a lot of their UXR style stock at 50 points off, so sales are quite brisk one would suspect

author: shapirus
author_rank: Super Contributor
timestamp: December 22, 2023, 03:32:38 pm
content: Quote from: jashugan on December 22, 2023, 02:44:55 pmBecause of their attitude. They don't deserve your money.See for example:https://www.eevblog.com/forum/testgear/keysight-officially-lost-the-plot-dont-buy-if-youre-a-hobbyist/https://www.eevblog.com/forum/testgear/a-broken-34470a-and-keysights-terrible-customer-service/

author: jashugan
author_rank: Regular Contributor
timestamp: December 22, 2023, 04:25:09 pm
content: Quote from: shapirus on December 22, 2023, 03:32:38 pmYou're right. But their 3000T series is awesome. With more memory, and eventually 12 bit, I wouldn't ever change it.

author: Dan_8123
author_rank: Contributor
timestamp: December 22, 2023, 05:08:38 pm
content: Just had that discussion with my Keysight dealer yesterday because I want to upgrade my current 3000A scope. He suggested the 4000A and when I mentioned that I'm more interested in something like the R&S MXO 4 or the newly released Tek 4 Series B (much more responsive UI than the old one) he said their only option was an EXR which costs at least twice as much, probably 3 times once you add the software packages.I'd love to stay with Keysight but their lower-end offerings just don't seem to keep up with the competition and no change in sight. He did mention on the phone that there will be a refresh of the 4000A sometime next year but couldn't give any more details than it being more of a software than hardware change. Maybe a G version?Doesn't sound like there's going to be a 10 or 12-bit version or modern UI any day soon

author: CosteC
author_rank: Regular Contributor
timestamp: December 22, 2023, 05:58:48 pm
content: I am under impression Keysight invests in top tier oscilloscopes and does not care about Siglent or Rigol. LeCroy seems to do similarly, just shamelessly rebrands Siglent for low end models.Btw Keysight scopes have hi-res modes. Maybe it is enough for thier customers so far?

author: mkissin
author_rank: Regular Contributor
timestamp: December 22, 2023, 08:50:45 pm
content: A large part of the problem with switching scope vendors is that they all use different proprietary probe interfaces.You can very easily end up with more value in your probes than the scope itself, which means switching vendors is hugely expensive.

author: CosteC
author_rank: Regular Contributor
timestamp: December 22, 2023, 10:03:23 pm
content: Quote from: mkissin on December 22, 2023, 08:50:45 pmSome vendors use different interfaces between series of scopes, which makes situation particularly frustrating.Same story is with DSLRs.BTW aren't fastest Keysight scopes using 10 bit ADCs?

author: tszaboo
author_rank: Super Contributor
timestamp: December 22, 2023, 10:15:33 pm
content: Quote from: CosteC on December 22, 2023, 05:58:48 pmWhy would you care about making 10-30% on a scope for 2000 EUR, when you can sell active probes for 90%+ profit for 10 times as much? They might be making as much profit on one probe than Siglent on 100 sold scopes.

author: Someone
author_rank: Super Contributor
timestamp: December 22, 2023, 10:29:18 pm
content: Quote from: CosteC on December 22, 2023, 10:03:23 pmS-series and UXR/MXR are but are $-$-$-$. Things like ENOB or noise are comparable to other 12bit ADCs but extra bits can still be useful.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: December 22, 2023, 10:58:09 pm
content: Quote from: Sighound36 on December 22, 2023, 03:13:29 pmI'm way more interested in UI responsiveness than boot time - HP/Agilent/Keysight has always been the leader in this respect. Give me the MSOX's UI speed over the RTB/RTM's speedy boot but but horribly slow UI any day

author: Martin72
author_rank: Super Contributor
timestamp: December 22, 2023, 11:03:07 pm
content: Quote from: CosteC on December 22, 2023, 05:58:48 pmWe have a saying here which goes like this:What does the oak tree care if a pig rubs against it...Keysight has had a completely different clientele for decades.If you're still making enough money with it today, why bother with low-end products?QuoteWhat do you mean by shameless? In my opinion, it's a kind of concession to have something like this on the shelf in case someone asks for it.They don't make any money out of it.At the moment Lecroy, Keysight, Tektronix have nothing to worry aboutThey have nothing to fear from Rigol, it's a different story with Siglent, but it will be some time before they become a serious competitor, in the sense of poaching customers, not in terms of technology, which is already not of bad parentage.R&S, on the other hand, are doing a clever job with their portfolio.They are already a bit further ahead than the other "big" providers.

author: PELL
author_rank: Regular Contributor
timestamp: December 23, 2023, 02:15:03 am
content: I guess because they have the best 10-bit ADC converter on the market.The important thing about a scope resolution is the "Effect Number Of Bits" or "ENOB".Many 12bits scope only has around 6~8bits of ENOB (depending on bandwidth and sample rate), while Keysight can easily reach this number with their 10bit ADC. One of my main guesses they actually design a 12bit ADC, but only say "it is 10bit" when marketing.Surely one day they will reach 12bit, but I don't think they will announce before they polish enough.

author: David Hess
author_rank: Super Contributor
timestamp: December 23, 2023, 03:24:51 am
content: I can think of a couple of reasons that they would not support 12 bits.HP/Agilent/Keysight seems to have held onto their old Megazoom ASICs for a long time. Do they support 12-bit acquisition records?Except for dynamic range, much of the advantage of a good 12 bit digitizer is lost unless the linearity and settling time of the analog signal conditioning can support it. That is a very tall order, and the only oscilloscopes that I have ever seen which did it are sampling oscilloscopes, but they cheat.It should be good for the noise level of FFTs, but check out the spurious free dynamic range.Quote from: CosteC on December 22, 2023, 05:58:48 pmDoes Megazoom work with hi-res mode?

author: BillyO
author_rank: Super Contributor
timestamp: December 23, 2023, 03:57:24 am
content: Quote from: mikeselectricstuff on December 22, 2023, 10:58:09 pmThere FTFY, Agilent and Keysight have little more than unfortunate history in common with HP. HP was quite possibly the best company ever, whereas those other two are, well, not.

author: Someone
author_rank: Super Contributor
timestamp: December 23, 2023, 04:47:59 am
content: Quote from: David Hess on December 23, 2023, 03:24:51 amYes and yes.

author: Martin72
author_rank: Super Contributor
timestamp: December 23, 2023, 05:35:26 pm
content: Quote from: PELL on December 23, 2023, 02:15:03 amThe Keysight 10bit converter is not bad - or it is generally hardly "better"...Edit: Not in the picture: Siglent SDS7000 H12: 7.5bits (3Ghz), 7.3Bits (4Ghz)Siglent SDS2000X HD: 8.7bits/8.4bits(100/350Mhz)

author: CosteC
author_rank: Regular Contributor
timestamp: December 24, 2023, 02:01:46 pm
content: Keysight 10 bit indeed does not offer anything inferior to R&S 16 bit it tektronix 12 bit but only at end of bandwidth. It is even better than Tektronix. For low frequencies LeCroy or R&S may be better solution without overpaying for not needed bandwidth needed for hi-res modes. Middle of shelf is bit empty for me (say 500 MHz.. 2 GHz)

author: 2N3055
author_rank: Super Contributor
timestamp: December 24, 2023, 03:35:30 pm
content: My opinion is that there won't be 12 bit megazoom 3000G HD scope from Keysight... Maybe never.3000T was "redesigned" into 3000G that is exactly same scope. Brand new one, just released year ago..Keysight now is like Fluke. Fluke 87V is "classic", set in stone in millions specifications, procedures. You don't change it. It sells exactly because it is always the same.Same is with Keysight 3000T/G.And same as Fluke, they invest and innovate plenty, just somewhere else. We spoke about it some time ago. Their corporate strategy changed form "manufacturer of premium measurement instruments" into "provider or premium measurement solutions".They are not interested in "low end". Which by their definition 3000 series is...So they will (like Fluke) keep legacy designs alive as long as there is market for them (it is minimum investment income) but will not develop new entry level instruments.It makes no sense. They lost that game long ago..

author: CosteC
author_rank: Regular Contributor
timestamp: December 24, 2023, 08:41:42 pm
content: I think this is very good summary.I used to use 34970A and it was withdrawn after decades. I had in my hadns HP 34970A, Agilent one and Keysight one.They introduced DAQ970A. Bit better here and there, basically same cards, our testers require some changes as DAQ970A is bit faster, it is black, and has better screen. Not used anyway in automated systems.Keysight is for me solution provider indeed. Very reliable, not cheap but it works very well. Somebody else will test if market really needs 12 bits, thier 10 bits is still better than most of competitors, and those who needs accuracy at GHz read datasheets carefully...

author: miro123
author_rank: Frequent Contributor
timestamp: December 24, 2023, 09:09:48 pm
content: Quote from: Martin72 on December 23, 2023, 05:35:26 pmCan you provide http link with screenshot data. I see mixing oF ENOB from manufacture A with Noise floor of B.Manufacture does not make coamprition easy. One define ENOB as linearity + Noisefloor in BW. Another freq flatness + noise , some other takes the gain error too, another use spectral density/THD/TDD. Other take the the horizontal errors also within the ENOBs.I want to read what exactly the published numbers means.As more as I read those screenshots as more confusing it gets - e.g Lecroy RMS noise floor at 1mv/div = 87uV. It is great value close to theoretical Johnson noise of 50ohm @25C . Lets calculate the SNR = 8mV pp /87uV - keep in mind that this is the best case number I divide Vpp to RMS noise SNR >1,1% or 6 bits SNR

author: Martin72
author_rank: Super Contributor
timestamp: December 24, 2023, 10:43:56 pm
content: QuoteThen I would take another closer look.You can only see the noise floor with the lecroy extractor, and only because the cut-out would otherwise have been too narrow.Here are the models for you to look at again:-Tektronix series 4B-Lecroy HDO6000B-Keysight Infinium S series-R&S RTO6 series

author: coppercone2
author_rank: Super Contributor
timestamp: December 24, 2023, 10:54:04 pm
content: keysight not so good with business 2 business relations either even if ur fucking huge like a cthulhu, there is tension with the old godsI am starting to think that either customer relations are there, or they are not there. The supposed customer relations that magically develop between massive entities are not really there either. Maybe its lack of practice or what, but its borderline litigious. The idea that there is some kind of filter for bigger companies is well, a bit of a myth. I see simple problems fester and fester with KS.p.s. no one deals with them directly, you use a TE broker or whatever, even if F500. Last someone tried direct KS relations they basically lost their sanity.p.p.s.for those big customer only sales support people, try working out the bugs and problems with the little people so you can actually fucking help the big people. their like beta testers. your department sux. its a slow unpleasant pain in the ass and prevents work and research from getting done. chances are the guy running a single TE in his garage had the same problem we do and you might actually have fixed it by the time we had a time sensitive cost sensitive problem. and you can learn some manners and practice discourse while you are at it. its a skill you develop and maintain through conversations with all sorts of people. the greeks knew this about 2500 years ago.

author: tooki
author_rank: Super Contributor
timestamp: December 26, 2023, 07:08:19 pm
content: Quote from: Dan_8123 on December 22, 2023, 05:08:38 pm4000G is already out, I had a quote for one back in October. But no news on any true upgrade to that hardware — 4000A->4000G is just like 3000T->3000G: basically no changes other than throwing in most of the software options by default.

author: Anthocyanina
author_rank: Frequent Contributor
timestamp: December 26, 2023, 08:03:07 pm
content: Quote from: tooki on December 26, 2023, 07:08:19 pmhuh, it's really out! very quiet release, 8 bits, of course, and also black. the white/beige ones looked so lovely

author: zrq
author_rank: Frequent Contributor
timestamp: December 26, 2023, 08:24:39 pm
content: Are these G version scope still Windows CE based? Or keysight finally moved away from this dead OS line (EOL 5 years ago I recall)?

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: December 26, 2023, 08:29:39 pm
content: Quote from: zrq on December 26, 2023, 08:24:39 pmI don't think they can even buy new WinCE licenses any more, which I think is why they changed the DSOX12xx to Linux

author: tooki
author_rank: Super Contributor
timestamp: December 30, 2023, 08:18:02 pm
content: Quote from: mikeselectricstuff on December 26, 2023, 08:29:39 pmWiki says OEMs can buy licenses through 2028.I didn’t realize Keysight had switched the 1000 series to Linux. Any difference in performance compared to the WinCE-based predecessors?

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: December 30, 2023, 10:12:02 pm
content: Quote from: tooki on December 30, 2023, 08:18:02 pmThe first release had significantly longer boot time, but they said this would be improved - I donated the scope to a hackspace so don't know what the current state is

author: tooki
author_rank: Super Contributor
timestamp: December 31, 2023, 02:45:33 pm
content: What about the real-time performance? The lack of UI lag is one of the things I like the most about Keysight oscilloscopes, at least the ones I’ve used (which are all WinCE-based units, including older 1000-series).

author: zrq
author_rank: Frequent Contributor
timestamp: December 31, 2023, 05:03:46 pm
content: Hmm, I would not call my experience with the DSOX2000 and 3000 lack of UI lag, especially when you try to drag the measurement cursors on the touch screen. The (half) built-in VNC remote control also runs at laughable frame rates like 1 or 2 fps.

author: tooki
author_rank: Super Contributor
timestamp: January 01, 2024, 02:31:21 pm
content: Quote from: zrq on December 31, 2023, 05:03:46 pmI’m not talking about remote control (admittedly a big downside to the Keysights). Have you used other oscilloscopes? Practically all have user interfaces that are slowereverywhere, all the timecompared to the Keysights. Many have UIs that I consider to be unusably slow.

author: HighVoltage
author_rank: Super Contributor
timestamp: January 01, 2024, 02:47:05 pm
content: Quote from: tooki on December 26, 2023, 07:08:19 pmI had no idea!And even if I do a google search, nothing comes up for the 4000GI also do not see it on German distributor sites.Is Keysight hiding their marketing for this 4000G scope?

author: Bud
author_rank: Super Contributor
timestamp: January 01, 2024, 04:17:53 pm
content: Quote from: tooki on December 31, 2023, 02:45:33 pmThe 1200x series (Linux) is based on same hardware as 1100x (WinCE) and FPGA binary is the same. I'd expect similar GUI performance between the two.

author: 2N3055
author_rank: Super Contributor
timestamp: January 01, 2024, 04:25:24 pm
content: Quote from: tooki on January 01, 2024, 02:31:21 pmI have used many scopes, including owning MSOX3000T.MSOX3000T has very fast reaction on physical buttons and knobs. But there are also things on it that are slow. FFT is slow. Search is slow. Decode from segmented memory first time is slow. But it is definitely optimized to feel responsive on most basic manual operations.OTOH even on DS1000Z that I definitely noticed it was much slower some time than Keysight, i never felt it was unusable or that it was a problem that would prevent me to do my job. So even if you can notice something not being as fast it can still be perfectly usable. That is definitely a topic where individual preferences and usage patterns are very important. If you spend lots of time sifting through deep memory or doing FFT that might be priority for you...So yeah, that is going to be very individual opinion. Some will care very much, some not at all.

author: 2N3055
author_rank: Super Contributor
timestamp: January 01, 2024, 04:30:20 pm
content: Quote from: Bud on January 01, 2024, 04:17:53 pmOther scopes struggle with priority given to reading user input on software side. WinCE as much as not getting much love, has that done very well. On Linux, it depends on what toolkit was used and how it was tuned. But, since Keysight has resources and if they took it as priority, I agree with you they might at least make it comparably fast. Even if not exactly the same they would tune it to be "close enough".

author: HighVoltage
author_rank: Super Contributor
timestamp: January 01, 2024, 04:33:02 pm
content: FFT is slow on all 3000x, 4000x, 6000x Keysight scopesThe older 7000 series like the MSO7104B is much much faster in the FFT and all other math functions.

author: tooki
author_rank: Super Contributor
timestamp: January 01, 2024, 04:58:31 pm
content: Quote from: 2N3055 on January 01, 2024, 04:25:24 pmI own the DS1000Z and know what you mean.The FFT and search aren’t UI elements as such. The Keysight’s UI for those remains very responsive, even if the functions themselves are slow. That’s what Keysight has absolutely nailed on its scopes: UI responsiveness. They never feel like they’re bogged down.As an example of what I mean, the R&S RTB2000 and RTM3000 I find to be unpleasantly slow, to the point that this alone excluded them from the running when I was selecting a new scope at work recently. The UI isalwayslagging behind you, so even basic things like moving a trace using the rotary encoder (never mind touch screen) are frustrating because you have to stop ahead of where you want to be. Scrolling through menus, same thing. The actual acquisition hardware is great, and the waveform update rate very good. But the UI is like molasses. (I ended up getting the MXO 4, whose UI is still slow compared to the Keysights, but what I consider just barely tolerable.)

author: tooki
author_rank: Super Contributor
timestamp: January 01, 2024, 05:16:23 pm
content: Quote from: Bud on January 01, 2024, 04:17:53 pmThat is a very, very incorrect assumption to make. UI responsiveness has nothing to do with the acquisition hardware performance as such: many (most?) modern scopes have incredible acquisition hardware, but struggle to create a UI for them that is responsive. And it’s perfectly possible to create a snappy UI for very slow acquisition hardware (for example, Saleae Logic and a basic 24MHz logic analyzer device.) The worst is when you have a slow UI whose design creates dependencies on the acquisition hardware, such that the hardware causes the UI to hang while it does stuff.The responsiveness of a UI hinges on many, many things, which is why the same hardware can be super responsive when running one OS or UI toolkit, and slow as molasses when running another. Among other things, memory footprint, memory management, amount of hardware acceleration used, functions available, amount of abstraction, algorithms chosen, skill of the programmers, choice of API, amount of compiler optimizations…Just as an example: I remember when Mac OS X 10.0 first came out in 2001. While it was super stable compared to Mac OS 9 on the same hardware, it didn’t yet leverage all that much GPU acceleration, so it felt sluggish compared to Mac OS 9 on the same hardware. 10.1 optimized some things, but when 10.2 introduced hardware acceleration for several more layers of the graphics stack, it really felt snappy for the first time. Again, on the same hardware. Mac OS 9 basically allowed programs to write directly to the screen, whereas Mac OS X used a buffer for each window, which then got composited (layered with transparency, etc) and double-buffered to the screen to avoid tearing. More capable, more robust — and slower, especially when not hardware-accelerated.What boggles my mind is how sluggish so many modern scope GUIs are, despite having application processors far more powerful than in older ones that were nice and snappy.

author: Someone
author_rank: Super Contributor
timestamp: January 02, 2024, 12:04:13 am
content: Quote from: 2N3055 on January 01, 2024, 04:25:24 pmFFT speeds are all over the place:https://www.eevblog.com/forum/testgear/new-keysight-scope-1st-march-2017/msg1265067/#msg1265067One area few people have been bothered to actually measure and compare.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: January 09, 2024, 11:32:00 am
content: Quote from: HighVoltage on January 01, 2024, 02:47:05 pmhttps://www.testequity.co.uk/Promotions/KeysightPromotions/Keysight4000GX-Series-Teaser

author: HighVoltage
author_rank: Super Contributor
timestamp: January 09, 2024, 11:33:54 am
content: Oh, coming out on January 15th!Thanks

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: January 09, 2024, 12:35:46 pm
content: Not sure if there's anything new here but there is a 50 page datasheet :https://www.distrelec.de/en/oscilloscope-infiniivision-4000g-dso-4x-5ghz-5gsps-spi-rs232-rs422-rs485-usb-keysight-dsox4154g/p/30407321

author: 2N3055
author_rank: Super Contributor
timestamp: January 09, 2024, 01:04:30 pm
content: Fun fact, old datasheet for 3000T has dual page photo of scope perfectly aligned between pages...4000G not so much... Looks weirdly amateurish....I know it's nitpicking about some photo in datasheet, but it shows how attention to detail is slipping as the time goes by...

author: skander36
author_rank: Frequent Contributor
timestamp: January 09, 2024, 07:11:57 pm
content: So, the OP ask about 12 bit KS scope and we ended up happy with an 8 bit "refurbished" scope ...Subcribe to the opinion that old WinCE on KS provide the most responsive UI.I also found WinCe on R&S FPC1500 but is not notably fast.

author: EE-digger
author_rank: Frequent Contributor
timestamp: January 15, 2024, 07:44:29 pm
content: "Meet the world's most advanced oscilloscope"That was the subject of a morning email from TestEquity. For a moment, I thought there would be something exciting. I owned an MSOX4154A for several years and sold it last year.I also have it's smaller sibling, the 3104T, which I love.But c'mon Keysight, a can of dark grey spray paint and that's about it? What about your screen resolution. Siglent and Rigol are eating your lunch. Had a client buy a Rigol RSA last fall and the screen was beautiful.Keysight needs to move the market forward or they will trail. The "G" isn't moving anything.4MPts memory depth? C'mon Keysight. That's like making us use a 4 function calculator instead of Matlab or other.That's the sad truth. This cow's been milked. There's nothing to love about the "G" series.And I'm ANGRY. Why? Because Keysight is American at its roots (yeah, I know the details). It's not designed in a country that hates us but loves our money ... not the people, the ... government. I don't want my next scope from a country that's hinting at WW3, which is insane. Ok, no politics here.

author: shapirus
author_rank: Super Contributor
timestamp: January 15, 2024, 09:09:19 pm
content: Quote from: EE-digger on January 15, 2024, 07:44:29 pmKeysight (as well as R&S btw) is still selling dual-use equipment to the terrorist entity commonly known today as Russia and doing "business as usual" there, which is not any less despicable than that.

author: David Hess
author_rank: Super Contributor
timestamp: January 15, 2024, 10:08:15 pm
content: Quote from: EE-digger on January 15, 2024, 07:44:29 pmMemory depth is usually more important for marketing than engineering. What matters more is the ratio between memory depth and bandwidth which determines how quickly the memory can be processed. Previous HP DSOs had limited acquisition memory because they had a custom ASIC for processing, and users seem to have loved the fast processing that allowed.

author: HighVoltage
author_rank: Super Contributor
timestamp: January 16, 2024, 09:33:52 am
content: Quote from: mikeselectricstuff on January 09, 2024, 12:35:46 pmThat datasheet is actually well made and gives a good overview of the 4000x series.But I do not see any reason to upgrade to the "G" model.

author: tooki
author_rank: Super Contributor
timestamp: January 16, 2024, 11:13:29 am
content: Quote from: HighVoltage on January 16, 2024, 09:33:52 amOf course not. The G models are simply a) color facelift, and b) include most of the options for free. There’s no difference in the hardware itself vs. the immediately preceding models.

author: Pinkus
author_rank: Frequent Contributor
timestamp: January 16, 2024, 11:32:08 am
content: Quote from: David Hess on January 15, 2024, 10:08:15 pmI second this. Very very rarely have I wished for more memory when working with my Keysight MSOX4024a. But (especially when I look at other oscilloscopes in comparison) I am grateful every day for the speed, responsiveness and usefulness of my scope.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: January 16, 2024, 12:15:58 pm
content: Quote from: Pinkus on January 16, 2024, 11:32:08 amDefinitey agree - even when you do hit memory limits, these can often be memory limits can often be mitigated by choice of acquisition mode, limiting channels etc. as well as smarter trigger/segmented setup.I have a MSOX3104T and R&S RTM3004 on the bench, and the Keysight gets 95% of the use despite the smaller screen and smaller memory - IMO the UI speed on the R&S is borderline unacceptable for a scope in its price range.

author: nctnico
author_rank: Super Contributor
timestamp: January 16, 2024, 01:22:44 pm
content: Quote from: David Hess on January 15, 2024, 10:08:15 pmThat depends on what you are doing. For circuits with microcontrollers / processors you'll need all the memory you can get. I used to have an Agilent model with the 8MPts Megazoom ASIC and that was not enough in many cases. Keep in mind that with the Keysight scopes you'll have 1/4th or even 1/8th of the memory available because it is shared amongst all channels (analog and digital).

author: 2N3055
author_rank: Super Contributor
timestamp: January 16, 2024, 01:56:24 pm
content: I have both MSXO3104T and several long memory scopes (2 x Siglent and Picoscopes).While Keysight is really fast to react to user controls, it really is very limited in some ways.As long as you reach certain time-bases sampling rate drops quickly.If you use it as you would a smarter CRT scope then it is fine.But very small memory is very limiting for some use cases.

author: David Hess
author_rank: Super Contributor
timestamp: January 16, 2024, 07:05:56 pm
content: Quote from: nctnico on January 16, 2024, 01:22:44 pmI would agree that in some cases record length is everything, but more often it is just for marketing where more is better. Record length can be objectively advertised, but how can fast response of the user interface and ease of use advertised?It is like how every new DSO is now advertised as "low noise", whether it really is or not.

author: EE-digger
author_rank: Frequent Contributor
timestamp: January 17, 2024, 03:30:12 am
content: I had several occasions where tens of megabytes of memory depth were needed for SPI to prove existence of processing glitches in a commercial chip. For this we switched to a Saleae 16 analyzer which filled the bill nicely. We performed rapid searches on the PC and proved the problem to ADI at the time. So this created a dividing line for which I no longer blame the Keysight scopes. Having this ability in the scope may have given completeness but not the best place for it to reside given PC speeds and space.

author: 2N3055
author_rank: Super Contributor
timestamp: January 17, 2024, 09:01:48 am
content: Quote from: EE-digger on January 17, 2024, 03:30:12 amThere are many occasions where you have glitches because of EMC, or some chip acting up. Some chips will react to very fast pulses and get confused.Using protocol/logic analyser is fine to find the erroneous message but will not explain why message is wrong. On CAN you can have bus collisions that will show as bad message. But you don't know why. That is why deep memory scope that will keep sampling rate in long captures, and be able to decode is useful..It really depends on what you do.

author: HighVoltage
author_rank: Super Contributor
timestamp: January 17, 2024, 09:51:03 am
content: Quote from: EE-digger on January 17, 2024, 03:30:12 amThis is a perfect combination with a scope and we might never see the abilities of a Saleae Logic Pro 16 in a scope. It always depends a lot on the application.For me, the Keysight scopes, 3000x, 4000x and 6000x are just perfect as they are.The only (small) option I am missing is to select what is saved on a screen shot.

author: tautech
author_rank: Super Contributor
timestamp: January 17, 2024, 09:54:36 am
content: Quote from: HighVoltage on January 17, 2024, 09:51:03 amHow so ?Reverse image ?No visible menu ?Trace colors user defined ?Trace labels ?

author: nctnico
author_rank: Super Contributor
timestamp: January 17, 2024, 11:14:16 am
content: Quote from: David Hess on January 16, 2024, 07:05:56 pmFast response is not the only thing and ease of use is debatable. Try to setup decoding on a non-touchscreen Keysight scope. It is a horrible experience even when compared to a relatively cheap brand like GW Instek.2N3055 is right on the money here:Quote from: 2N3055 on January 16, 2024, 01:56:24 pmIn that light it would make a lot of sense for Keysight to come up with a 12 bit version. Unless they can't put one on the market for a competitive price.

author: HighVoltage
author_rank: Super Contributor
timestamp: January 17, 2024, 11:21:59 am
content: Quote from: tautech on January 17, 2024, 09:54:36 amSee enclosed typical screenshot of the 4000X scopeI would like to:1. Select the text that is shown up on the top of the screen (Custom Text)2. Definitely be able todisablethe serial number and Firmware version of my scope on the top3. Enable or disable the time and date at the bottom right of the screen shot(And why do I have the date and time at the top and bottom?)4. Be able to select 12h or 24h system to show.Best scenario would be a custom text with option of an incremental number in the text.Same is true for the 3000x and 6000xBesides these little things I am very happy with these Keysight scopes.

author: 2N3055
author_rank: Super Contributor
timestamp: January 17, 2024, 12:34:57 pm
content: Quote from: HighVoltage on January 17, 2024, 11:21:59 amTop line is snapshot data.Serial and FW version are there for traceability. It is a good thing.But I see no reason why it cannot be made configurable for those that want to disable it.Time down left is part of the screen. It is a screenshot.I also cannot comprehend that after 10+ years of platform, Keysight cannot give us 24h clock....

author: Wolfgang
author_rank: Super Contributor
timestamp: January 17, 2024, 02:00:06 pm
content: Quote from: Martin72 on December 23, 2023, 05:35:26 pmAnother point is the advertising method about resolution. Many bits on paper look nice, but the only thing that really counts is effective bits (ENOB). These figures are *always* below what the ADC can deliver,and that means that the ENOBs of 12bit ADCs are around 10 at best.See here:https://electronicprojectsforfun.wordpress.com/to-enob-or-not-to-enob/It has become a fashion to brag about resolution (e.g., R&S claims "up to 18bits" for their MXO4 and 5), but not to give ENOB numbers. That is deliberately misleading. Keysight and even Rigol are serious andhave their ENOB values documented. Ironically, R&S even has a paper discussing their pro scopes and why ENOB is important. Only their own marketing department did not get itfor the MXO4 and 5.The R&S paper is here:https://scdn.rohde-schwarz.com/ur/pws/dl_downloads/dl_application/application_notes/1er03/ENOB_Technical_Paper_1ER03_1e.pdf

author: 2N3055
author_rank: Super Contributor
timestamp: January 17, 2024, 02:45:01 pm
content: Quote from: Wolfgang on January 17, 2024, 02:00:06 pmR&S is "selling" Hires mode as real bits..Siglent for instance not only publishes ENOB figures but unlike some others also specifies how published number was measured.From datasheet for SDS2000X HD :ENOB*1 (typical):(350 MHz) 8.4-bit, (200 MHz) 8.6-bit, (100 MHz) 8.7-bit* 1：99.99 MHz input(100 MHz model uses 49.99 MHz)，-0.5 dBFS，20 mV/div，50 Ω input impedanceMany manufacturers have the all the numbers, marketing don't care.Generally speaking marketing always speaks only off things that they can leverage as perceived advantage. They emphasize what they have...While Keysight is talking it's ass off how important wfms/s is when talking about Megazoom scopes, they don't even mention it on Infinium-S series. Cause it has really low wfms/s because it is long memory analytical scopes. In datasheets for those it is all about how large memory is great..So which one is true?

author: David Hess
author_rank: Super Contributor
timestamp: January 17, 2024, 07:02:49 pm
content: Quote from: 2N3055 on January 17, 2024, 02:45:01 pmMarketing may also drive engineering.During the Tektronix 22xx and 24xx era of DSOs, engineering came up with a way for the DSO to indicate that aliasing was likely present; just compare the trigger frequency with the sample rate. So they had a prototype with an indicator to show when aliasing was present. Leaving aside how useful this might be to inexperienced users, and keep in mind that everybody was an inexperienced user as far as DSOs back then, this feature was obviously dropped because it implied that Tektronix DSOs suffered from aliasing when their competitors did not.Is there any actual use for the ENOB specification? I would rather know the SFDR (spurious free dynamic range) which is directly observable with an FFT, and very likely where they are calculating the less useful ENOB from anyway.Oscilloscopes used to specify aberrations, which is roughly equivalent to settling time. I imagine these specifications would look especially bad on 12-bit and higher resolution instruments, some of which will never settle. One reason sampling oscilloscopes are useful at lower frequencies is overload immunity and instant settling time.

author: tooki
author_rank: Super Contributor
timestamp: January 17, 2024, 08:08:42 pm
content: Quote from: 2N3055 on January 17, 2024, 02:45:01 pmHow do you figure, given that the MXO 4 and 5 have 12-bit resolution all the time (the native resolution of the ADCs) and have a "high def" mode you can enable on top of that?

author: Wolfgang
author_rank: Super Contributor
timestamp: January 17, 2024, 08:45:43 pm
content: Quote from: tooki on January 17, 2024, 08:08:42 pmLets stick to physics:- There are never more bits than an ADC can provide. Everything else is done by boxcar averaging and oversampling. While this can reduce noise, it will only make the inherent nonlinearities of the ADC more visibleThese nonlinearities create spikes in the spectrum, automatically reducing dynamic range and also the resulting ENOB.Most serious ADC chips have ENOB specs, depending on sampling rate, signal frequency, amplitude, ... The R&S MXO uses a Texas Instrument ADC (not even a bad one), and this one has ENOB values around 10according to its datasheet. So - soory - no magic anywhere, except for the marketing guys who may plead incompetent.An extreme (low frequency) example of a huge discrepancy between ADC resolution bits and useful bits are 24-32bit ADC used for digitizing. *Several* of the lower bits just drown in noise, still these ADCs are in the worlds best multimeters.Its the linearity that makes an ADC premium.

author: 2N3055
author_rank: Super Contributor
timestamp: January 17, 2024, 09:05:02 pm
content: Quote from: David Hess on January 17, 2024, 07:02:49 pmThank you for interesting story!I believe it was dropped because it was not very useful, except in case of sinusoidal signals. And sounded bad like you said.As for specifications, all the specifications are useful for somebody... ENOB was mentioned because of bits mentioned, because not all bits are same.I agree with you that it would be nice if more of critical data would be specified. SFDR, SINAD, results ot two tone test (IMD) etc..But I guess that gets complicated fast. With attenuators, VGA etc. you get many combinations of signal path to ADC, so that would be complicated tables of all the specs in all combinations...

author: electr_peter
author_rank: Unknown
timestamp: January 17, 2024, 09:53:47 pm
content: Quote from: David Hess on January 17, 2024, 07:02:49 pmInteresting story. Need to think how useful (or not) this feature would be.I think that current DSOs could show something related on the screen. A popup of some sort can light up whenever sampling rate is <2x of scope nominal BW (or with selected 20MHz BW filter 40MS/s or less). This is left to the user AFAIK - actual sampling rate is shown, but it is not immediately obvious if it is sufficient.Such popup would at least indicate that some signals may alias and sinc interpolation may not be appropriate. DSOX3k scopes solve these problems behind the curtains so to speak (via random decimation and by disabling sinc interpolation with lower sample rate).

author: David Hess
author_rank: Super Contributor
timestamp: January 18, 2024, 01:22:23 am
content: Quote from: Wolfgang on January 17, 2024, 08:45:43 pmNothing prevents having a converter with greater linearity than its resolution will support, but they are rare and except as describes below, I am not aware of any fast ones.Modern fast ADCs all seem to be pipelined subranging types with 3 or 4 stages in series, with the earlier stages having a linearity much better than their low 3 to 5 bit resolution will support because it directly affects the later stages. Error correction then discards some of the generated bits to produce the specified resolution at the interface. Multiples of these subranging converters are interleaved for even higher sample rates and their self calibration encompasses this as well.Quote from: electr_peter on January 17, 2024, 09:53:47 pmSome of the appeal of what the Tektronix designers did was because it was so easy to do on these early DSOs. They all included high speed level triggering which operates very much like a data slicer, so comparing the processed trigger signal to 1/2 of the sample rate will immediately reveal aliasing. The only thing required was a simplified frequency counter.

author: Wolfgang
author_rank: Super Contributor
timestamp: January 18, 2024, 11:27:39 am
content: Quote from: David Hess on January 18, 2024, 01:22:23 amAgreed, but none of these tricks can be used in scope front ends with high sampling speeds. The "naked" linearity is what counts there, and there seems to be no way around that, AFAIK.

author: nctnico
author_rank: Super Contributor
timestamp: January 18, 2024, 12:38:56 pm
content: Quote from: electr_peter on January 17, 2024, 09:53:47 pmI agree. A light goes on saying what you see is not what you got. And then???IMHO peak-detect is a much more useful feature to prevent aliasing. At least you can see the extremes of the signal.

author: David Hess
author_rank: Super Contributor
timestamp: January 18, 2024, 03:13:32 pm
content: Quote from: Wolfgang on January 18, 2024, 11:27:39 amWhich tricks are you referring to? Modern subranging ADCs work exactly like I described from 100s to 1000s of millions of samples per second. They use the extra bits generated in each stage to improve linearity and remove missing codes (1), and then use a separate self calibration step to interleave multiple converters for even higher sample rates. And this is all found in the cheapest DSOs today! How amazing is that?(1) Missing codes are produced by a DNL (differential non-linearity) greater than 1.Quote from: nctnico on January 18, 2024, 12:38:56 pmBack then peak detection was the exception rather than the rule because the required high speed logic was not trivial to implement. It was very quickly moved to high speed custom logic.

author: Wolfgang
author_rank: Super Contributor
timestamp: January 18, 2024, 10:33:43 pm
content: Regardless of the way how ADCs do it, the remaining nonlinearities lead to ENOB reduction. Show me a single piece of ADC hardware that really achieved more bits that the ADC at RF speeds.