Understanding Entry Level Scopes? (Limitations & Uses) - Page 1
Forum section: electronics / testgear

author: Binaryb3n
author_rank: Contributor
timestamp: August 07, 2016, 04:50:15 pm
content: Hello, I'm fairly new to electronics and I've posted in the general section about myproposed list of tools I want to buy. I thought I would start a different thread regarding scopes though, as I have more technical questions about them.The first reply to the before mentioned thread said I'm probably not going to get far without a scope when it comes to embedded electronic projects, and I would like to focus on getting one anyway - especially for decoding various protocols and debugging circuits. The question I suppose is, how much scope does one need? And how do you work that out?The default recommendation seems to be the Rigol DS1054Z with the hack to make it 100MHz. Additionally, It was both the suggested scope in the other thread and the one I have been looking at anyway. I've also been looking at the Siglent ones, but I'll be the first to admit I don't know a lot about what I am looking for.If you were only going to buy one digital scope, would it be the DS1054Z, or would you be looking at a more expensive 2000 series, or even another brand? What sort of projects/debugging would the DS1054Zstruggleto be useful for? I.e., what are the limitations in an applicable/relatable sense (whatcan'tI do with a DS1054Z)? As mentioned in the other post, I am seeking to buy tools that I will buy once and use for the next 10-15 years without wanting for much more. It's okay if I don't get to use the full functionality straight away, I would prefer that features I will need within the next 24 months are there when I need them though.Secondly, it seems like a common suggestion is to buy a second hand analog scope. What features would I be looking for in an analog scope to pair with a newer digital model? And lastly, would it make sense to buy a USB tool like the Digilent Analog Discovery 2 for "extra channels" and the function generator feature?

author: nctnico
author_rank: Super Contributor
timestamp: August 07, 2016, 05:12:06 pm
content: Did you use the forum search function (use the word 'review') and read the threads about the various oscilloscopes?

author: Binaryb3n
author_rank: Contributor
timestamp: August 07, 2016, 05:15:29 pm
content: Well I used Google with the site: parameter, but yes. I didn't really find much about what they can't do though, just that people were overall happy with the DS1054Z, despite a few odd quirks.As I'm essentially new to the world of electronics, I was hoping someone could help point me in the right direction, or better still, provide some examples of what it can't do, so I can figure out if I will need something more powerful. Ideally, I want to own one digital scope and preferably own it for a while without needing to upgrade.For example, for anyone that owns a DS1054Z, are there any real world examples of a problem it couldn't debug, or a project you couldn't test and build with it? Obviously it's good for it's price. But what about for outside of it's price. What sort of projects does a more expensive scope "unlock"?

author: rstofer
author_rank: Super Contributor
timestamp: August 07, 2016, 05:27:30 pm
content: I've been messing around with electronics for about 60 years. I built my first oscilloscope when I was around 12 using plans in the ARRL Handbook (I believe). It wasn't much of a scope but I learned a lot. Anyway, I've been doing this stuff for a while...I had an old Dumont scope for a while but it was pretty useless. I move up to a 10 MHz dual channel Heathkit (which I built) and it was adequate for many years. When I retired, I treated myself to a Tektronix 485 which I still have. It is an analog 350 MHz dual channel scope that I picked up off eBay for $200. It's a great scope and I could get along with my projects using just this scope. Mostly I work on embedded stuff and, more often than not, FPGA projects. How do I get along? Well, I have the project generate very specific trigger signals so the scope is looking at exactly my point of interest. I don't need to store 2 days worth of samples and search through them, I know exactly what I am looking at. It's the user, not the tool!But I never had a digital scope, didn't know if I needed one (and truly, I didn't) but I decided to see what they were all about. I liked the idea of 4 channels, that was a 'requirement'. In fact, it was the driving force. It's easier to work with SPI on a 4 channel scope. Easier, not compulsory. So, yes, I bought the DS1054Z KNOWING that it had warts at the margins. There's a lot to learn about using a digital scope. I didn't know anything about digital scopes, didn't know if I would even like one after about 60 years with analog scopes but there's no time like the present to learn.Bottom line: I like the scope a lot. My grandson is just starting an EE program in college. He may get a lot of use out of the scope!As to the Digilent Analog Discovery: I have the first version and I use it a lot - particularly on embedded kinds of things but also for messing around with analog circuits (including analog computing). There's nothing like a 27" scope screen! Given that the PC has two 27" screens, I have a lot of flexibility about what I display (including the IDE for code). There'a a lot of electronics that can be done with the AD as long as you can live with its limitations in terms of voltage input. Since I mostly work on 3.3V and 5V circuits, there is no problem. Of all the possible USB solutions, I like the AD the most. Two scope channels, two signal generators, dual power supplies, 16 digital IO (including logic analyzer functions), what's not to like? I can carry it in my laptop bag and I'm ready to work. Or play... I'm retired, I don't work!I probably stand alone with the opinion that this device can put off the purchase of a scope for a very long time. Try doing network analysis with a scope! That is a very nice learning tool when it comes to filters.I don't know what I can't do with a 1054Z so I'm no help. It does everything I could possibly imagine and a lot of things I will never use. Is it the end-all, be-all of scopes? Probably not. It has limited bandwidth so it doesn't properly display signals with high frequency content but neither does any other scope. Even my 350 MHz scope is bandwidth limited. The limitation just turns out to be a lot higher... That 100 MHz square wave is going to look a lot like a sine wave on a 100 MHz scope.The measurement features are terrific! It's just a confidence booster when the scope gives a measurement that matches with what you already know about the signal. Being able to make detailed waveform analysis is terrific. Using the cursors to measure time between events is a lot easier than squinting to line the trace with the graticule. I actually used that feature yesterday to make sure I met the hold time on the chip select signal for SPI. Very easy to do! I was showing my grandson how RC servo signals worked - the scope displays the exact width of the servo pulse. No messing around, the number is right there on the screen!I'm keeping my DS1054Z. I could have spent a lot more money but for my needs, this scope is perfect.

author: Muxr
author_rank: Super Contributor
timestamp: August 07, 2016, 05:31:08 pm
content: The reason why Rigol DS1054Z is such a commonly recommended beginner scope is because at its price it really has no rival.. when you consider an easy hack that unlocks all the features there is really no scope that offers that much bang per buck at that price point.The biggest limitation of the Rigol DS1054Z compared to its bigger DS2000 cousin is bandwidth and sampling rate. The DS2000 also has a bigger screen that might play a part in your decision as well if you have issues reading smaller fonts. Rigol DS1054Z however has 4 channels while DS2000 has only 2. DS2000 can also be unlocked/hacked to 300Mhz and it has the twice the sampling rate at 2Gs/s.Chances are for most hobby projects 100Mhz 1Gs/s is probably sufficient.. but if you need that extra bandwidth and sampling rate than DS2000 is an option.Once you start looking into $1000+ scopes your options widen greately. At $2k for instance you can score some pretty great used scopes on the 2nd hand market if you're patient and willing to take a chance.Generally speaking Rigol, Siglent, Owon.. fall in the category of B-brand scopes. While they are all generally well built hardware wise.. the firmware is often riddled with bugs and half implemented features. There is a noticeable and often quite big difference in quality of software between those scopes and the scopes from A-brands like Keysight, LeCroy, Rohde & Schwarz...I can give you some examples of what I mean. Rigol's DS1054Z is loaded with features.. and while the main timebase function of the scope generally performs well.. the serial decoding is implemented poorly. Instead of decoding the actual signal the decoder only decodes from the screen's frame buffer. So if the signal isn't the best and your scale isn't adjusted for maximum resolution you will get decoding errors. That's just one example.Generally for serial decoding on a budget, getting a dedicated Logic Analyzer for decoding is the way to go.. Saleae is my favourite option there.. and you can pick up a clone for dirt cheap as well.Many still recommend the DS1054Z despite the shortcomings like these because it performs well in its main function.. and for the price it's an unbelievable bargain.I would stay away from the old Analog Scopes. Digital storage scopes offer so many nice features like the ability to do single shot capture, or display a plethora of measurements which makes a DSO is a no brainer. Analog Scopes have their charm and uses but for your first scope DSO is the way to go imo.

author: rstofer
author_rank: Super Contributor
timestamp: August 07, 2016, 05:44:44 pm
content: OK, here's a real world problem that the 1054Z can't solve: Display a 1 GHz carrier with some high frequency modulation.Every scope has limitations, bandwidth being foremost. Channels being next, in my view.Are there limitations to the 1054Z? Of course! Will you run into them in your lifetime? Doubtful... Think about your context: You want to work on embedded kinds of things. Well, you can't probe the core so the only thing you can look at are the pins and not many of those will be running over 60 MHz. Even the crystal frequency will be well below 100 MHz because there will be a PLL to generate the higher frequency clocks. Even my FPGA projects toggle pins at around 50 MHz. It is possible that they might go faster but when they do, I am usually using a logic analyzer.Besides, you can always consider the 1054Z as a beginner tool. Use it for a few years, sell it for some discounted price and move up. You can get a lot of use out of a 100 MHz scope. But, really, if you can afford one of the high dollar Keysights, why not? Here's one:http://www.newark.com/keysight-technologies/msox3104t/oscilloscope-20-ch-1ghz-5gsps/dp/93X6316?CMP=KNC-GUSA-GEN-SHOPPING-NEW-KEYSIGHT-TECHNOLOGIES&ad=81605889141&gclid=CLfmjZfsr84CFRSPfgodY7sKpAA mere $15,000 and you're good to go! And don't think for a moment that the 1054Z is anywhere near as capable. But it's also 1/40th the price!The 1054Z is an 'entry level' scope. That means it is a good 'first' scope, probably not the 'last' scope. Clearly, it would be out of place in a very high tech lab unless it was the designated 'beater' scope. But it certainly meets my needs!

author: Kilrah
author_rank: Unknown
timestamp: August 07, 2016, 05:50:14 pm
content: Quote from: rstofer on August 07, 2016, 05:27:30 pmI've just bought an AD2 for the versatility/convenience/small package as well, and it's an incredible little device. I'd love to justify a nice 4CH MSObecause I wantbut to be fair the AD2 can really do anything I need it for these days (MCU work, R/C signals, digital protocol debugging, some basic FPGA stuff). I never really needed the 60MHz bandwidth of my previous digital scope in many years, so I'm not worried about being short with the AD2's 30MHz... or at least not often enough to really say I need a 100MHz+ scope right now.There's that saying that something that can do everything always ends up doing none of them well, but in this case the level of all the things it offers is really good enough for most things.And the compactness means that even if I needed / could buy a nice expensive scope in the future the AD would still be the one that gets carried along for mobile use unless there's a real good reason to take the big one.Another cool thing to consider with the AD2 is that its 2 scope channels are differential, and a common use for more than 2 channels on a scope is using them for differential measurements - so as long as you can stay within the voltage limitations the AD2 can actually do things that would usually require a 4-CH scope.

author: nctnico
author_rank: Super Contributor
timestamp: August 07, 2016, 06:59:35 pm
content: Quote from: Binaryb3n on August 07, 2016, 04:50:15 pmTechnology is moving too fast for test equipment like a scope to be useful for 10 years or more. I think you can group the various brands as following though:1) Hantek, Owon, Rigol, Siglent (and rebadges): low cost but beware of bugs, useless features (like 1kpts FFT) or even missing features.2) GW Instek, Hameg: mature feature rich products but still good value for money and may be a good alternative for more expensive A-brands3) Keysight, Lecroy, Tektronix, R&S, Yokogawa: very mature products but expensive when it comes to value for money unless there is no alternative from group 2At the end of the day any DSO will show a signal but the (big) differences are in the advanced features like measurements, LAN connectivity, remote programmability, math, decoding, triggering, FFT. Do not be fooled by extremely long memory or insanely high waveform update rates. Long memory needs lots of processing power which many scopes simply don't have. High waveform update rates over 1000 waveforms/s don't really make an oscilloscope better or easier to use. Still choosing the right oscilloscope is though. If you are into microcontrollers having decoding for UART, SPI and I2C is a must have to solve problems which can be either in the analog or digital domain. Digital channels (MSO) may be a nice feature but those are also easely covered by an external (USB) logic analyser. There is also a trend for integrated waveform generators but usually these are more expensive than a seperate function generator and IMHO a seperate function generator is just easier to control.

author: zapta
author_rank: Super Contributor
timestamp: August 07, 2016, 07:12:20 pm
content: Quote from: Binaryb3n on August 07, 2016, 04:50:15 pmThe 1045Z will serve you well for many years. For protocol debugging you may want to get a logic analyzer (e.g. a Saleae or a clone). If you have spare money you can look for a nicer scope (better user experience, no fan noise, more reputable vendor, etc) but functionality wise it should be just fine.Focus on your projects, rather than on the equipment. It's a common trap for young and old players.

author: Binaryb3n
author_rank: Contributor
timestamp: August 08, 2016, 04:45:32 am
content: Thanks for helping me wrap my head around it all everyone. So to clarify:A DS1054Z will last me for several years at least most likelyI could possibly spend $2k+ or so for a more feature filled scope, but by the time I make use of all the features, the same money may end up buying a better scope because of how fast technology moves? And a DS1054Z will do what I need in the mean time.It would make sense to grab an AD2 and/or Saleae to pair with a DS1054Z (still cheaper than a more expensive scope and a good combination of features)How accurate is this?If I am getting me head around it, then I will probably end up buying a DS1054Z and an AD2 and/or Saleae. If it ends up being a "beater" in the future as someone called it, and I can get a better scope in the future than what the same money would buy today, I expect that the DS1054Z will still represent good value.Looking at prices, it seems I could easily spend as much money on a scope as I want to spend on setting up an entire workbench. I guess this only makes sense if it has every tool needed, but I don't think it does.So thanks for convincing me not to get a multi thousand dollar scope (yet).What sort of things generate a signal greater than 100MHz (mainly out of curiousity the most part now) that I might want to measure? Anything from working with amps or motors? (Audio and robotics projects) Again, if I don't need it then that really is good news! Just want to be sure.Quote from: Muxr on August 07, 2016, 05:31:08 pmOut of interest, would you recommend an analog scope as a good complementary scope to a (relatively) cheap DSO? If so, what should I be looking for in an analog scope and what sort of budget would I be looking at? Or at this point - would it just better to spend the combined money on a slightly better DSO like the DS2000 series?

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: August 08, 2016, 05:24:56 am
content: Quote from: Binaryb3n on August 08, 2016, 04:45:32 amWould you think horse and buggy is a good complementary to a modern car?There's no point in getting an analog scope if you have a half-decent DSO, unless you're into antiques or get one for free or a few bucks as a curiosity item.QuoteHardly. Get a starter scope like the mentioned Rigol DS1054z (although I'd rather get a GW Instek GDS-1054B which is in the same price range as a more mature alternative, though), and later down the road when you find yourself having outgrown you scope then you might want to start a look at a more advanced big brand scope anyways.

author: Muxr
author_rank: Super Contributor
timestamp: August 08, 2016, 05:52:40 am
content: Quote from: Binaryb3n on August 08, 2016, 04:45:32 amA scope can last you more than just a couple of years.. it depends on how fast you outgrow it really. It's not uncommon to see people who are happily using 20+ year old scopes. The main function of a scope, the ability to see signals on a given time base will never get outdated. Where you might outgrow it is perhaps some features you might find handy or the bandwidth needed to measure some specific thing you're working on beyond your current scope's capability.Quote from: Binaryb3n on August 08, 2016, 04:45:32 amHigh speed buses or communication gear can require high bandwidth to measure. Of if you're looking at really fast instrumentation analog circuits, physics research etc... But chances are a few thousand dollar scope may still not be able to measure those things either, some require $10k+ dollar scopes or more (the cost ramps up really quickly). And those specialized high bandwidth scopes are generally not well suited to your day to day use anyways. They can be slow to boot, and can have very sensitive channels you really have to know how to use effectively without damaging them.Audio stuff can be accomplished with a 20Mhz scope.. DS1054Z will be more than sufficient for robotics and motors.Quote from: Binaryb3n on August 08, 2016, 04:45:32 amI wouldn't really. They can be fun to use and can still be useful, but chances are since you're just starting out.. there is plenty of other gear I would get in a new lab over a 30 year old analog scope.Things that come to mind:- Soldering station and a Hot air rework station- Signal generator- Microscope- Power Supply- DC load- LCR meter- 2-3 multimeters (maybe a clamp ampmeter)Various other mechanical tools and accessories like an ESD mat. And most importantly components. Components for your prototyping can be expensive and you need to budget for them too.Start with essentials and as you gain experience and branch out to a field you like you can figure out what more specialized gear you need.

author: Muxr
author_rank: Super Contributor
timestamp: August 08, 2016, 06:07:45 am
content: Quote from: Wuerstchenhund on August 08, 2016, 05:24:56 amYeah GW Instek GDS-1054B looks pretty appealing. Don't think there is a hack for it, is there? But yeah even at the $800 it might be worth it over the old standby DS1054z. Bigger screen, faster operation, usable FFT and better decoding.

author: Berni
author_rank: Super Contributor
timestamp: August 08, 2016, 06:09:16 am
content: You can hardly go wrong with a DS1054Z.Thing is there is no such thing as a jack of all trades scope. You can find a really expensive scope that might be a close but not quite get there. For example looking at keysights layout of scopes. There are the x2000 to x6000 scopes that all have a pretty similar feature set, but go up in performance as they get more expensive, but none of them does things like eye diagrams, PCIe decode, USB 3.0 compliance tests etc. To get the high end features you need to go for the 9000, 90000, S-series etc scopes. But these scopes are windows PC based so they have longer boot times, no built in wave gen, really slow update rates of like 1000 updates (versus 1 milion on the x3000 due to its ASIC rendering)That rigol will do pretty much 99% of things a hobbyist wants to do with it. Perhaps its main limitation is the 100MHz bandwidth, but that only really becomes a issue when dealing with high speed digital (this does not include arduinos).If you find many years down the road that its not cutting it anymore just buy another better scope. At that point you will know in what area is it not cutting it for your specific needs so you can buy the scope with the features you really do need, as well as in 5 or 10 years there will be even better scopes on the market for a even lower price. Also if you do get a better scope, do hold on to the rigol as its small size,light weight and quick boot time is useful when you just simply need a scope somewhere to check if a clock signal is there or something.

author: zapta
author_rank: Super Contributor
timestamp: August 08, 2016, 06:16:33 am
content: I would highly recommend start designing and building projects now, even if you don't have all the possible equipment. As you go you will see what you need and what you don't, and you will also figure out if this is something you really want to do on the long run. You don't want to end up with a pile of fancy equipment that was never used while you move to your next hobby. Equipment is the mean, not the goal.

author: Berni
author_rank: Super Contributor
timestamp: August 08, 2016, 07:18:56 am
content: Quote from: zapta on August 08, 2016, 06:16:33 amWise wordsI been working with electronics for years without any scope.

author: nctnico
author_rank: Super Contributor
timestamp: August 08, 2016, 07:31:03 am
content: Quote from: zapta on August 08, 2016, 06:16:33 amThis isn't bad advice but it never hurts to try a piece of equipment and see if it is useful. Buying used equipment is a great way to learn about equipment; if it doesn't suit you you can always sell it again without much loss.

author: Assafl
author_rank: Frequent Contributor
timestamp: August 08, 2016, 07:33:52 am
content: I have been doing electronics since I was 11 years old, and have gotten along fine without a scope (teaches you a lot about how to build a circuit to figure out if the signal you "assume" is there is "indeed" there...). But my guess is that if the prices of scopes back then were anywhere as low as they are now, I would have saved up and purchased one (with help of parents and grandparents in combination with a b-day gift).As for choosing a scope - as usual the case with digital electronics is whether one goes with an older device (more mature firmware - but development ceased due to nearing EOL) or going with the newer equipment, learning to live with the evanescing bugs - and seeing the value increase as newer firmware gets released.I opted for the Rigol for home lab use and love it - and unlike many here who have not used what is called "a real scope" - I've used Tektronix and HP and Anritsu for 20 years.So perhaps I fall into the camp that thinks all T&M is crap and all measurements (meaning traceable to a physical unit) must be done with utmost concentration and care and the Rigol neither helps - nor detracts - in that respect. If you want to be able to say *with confidence* "500mV RMS input to the amp" - you have to learn how to use T&M equipment - what it measures and how it measures it - so you won't make a mistake - and the Rigol is no different from an HP or a Tek or Anritsu or B&K.Confidence is at the base of the argument between scope likers and haters - but as many lab rats or metrologists will say - it not "the equipment" - but the ability to "use it correctly". What does this mean? Obviously - it means that one cannot make an 8.5 digit DMM measurement without an 8.5 digit DMM - but also that most people cannot make a 8.5 digit DMM measurement even if they had a calibrated 8.5 digit DMM (for many reasons, noise, cable losses, temperature drifts, etc.) - Period. It takes experience and a through understanding of what you are trying to achieve.I think the peanut gallery is 100% wrong in associating price with confidence: As an example - Dave says (and I applaud him for saying so) get two cheaper DMMs rather than one expensive one so you can gain confidence in your readings: always compare - to see one didn't drift off.

author: Fungus
author_rank: Super Contributor
timestamp: August 08, 2016, 09:59:30 am
content: Quote from: Binaryb3n on August 08, 2016, 04:45:32 amQuote from: Binaryb3n on August 08, 2016, 04:45:32 amNo. Forget about analog scopes. Everything said about them two years ago no longer applies.Plus: You mention "embedded electronics". That implies microcontrollers and that means digital.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: August 08, 2016, 11:04:51 am
content: Quote from: Assafl on August 08, 2016, 07:33:52 amInteresting, since Anritsu doesn't even make oscilloscopes (they have BERT scopes for optical signals, which are something different)Besides, there are lots of members on this forum who use "real oscilloscopes" (whatever that means) pretty much daily. Not everyone here is a hobbyist.

author: Fungus
author_rank: Super Contributor
timestamp: August 08, 2016, 11:52:00 am
content: Quote from: Assafl on August 08, 2016, 07:33:52 amYep. The numbers on screen are meaningless unless the probe is connected properly and all the impedances, etc., taken into account.99% of what a 'scope is normally used for is looking at theshapeof waves on screen. Bandwidth is the only parameter that counts for that and the cheapo Rigol has more bandwidth then just about anything below $1000 or so.Really that should be the end of the argument, right there. Everything else is secondary.(except maybe number of channels and memory depth, but the Rigol wins there as well...)Quote from: Assafl on August 08, 2016, 07:33:52 amAgree 100%, two $5 showing the exact same reading gives almost the same confidence as a single Fluke 87V.If an RMS reading is critically important then double-check it using a true RMS multimeter, not by spending more money on the 'scope.

author: tautech
author_rank: Super Contributor
timestamp: August 08, 2016, 12:13:09 pm
content: Quote from: Fungus on August 08, 2016, 11:52:00 amhttp://siglentamerica.com/pdxx.aspx?id=4688&T=2&tid=1

author: Fungus
author_rank: Super Contributor
timestamp: August 08, 2016, 12:25:51 pm
content: Quote from: tautech on August 08, 2016, 12:13:09 pmSo... about twice the price for more bandwidth.(and serial decoders, etc., are extra).

author: rf-loop
author_rank: Super Contributor
timestamp: August 08, 2016, 01:26:27 pm
content: (Quote from: Assafl on August 08, 2016, 07:33:52 am)^2

author: nctnico
author_rank: Super Contributor
timestamp: August 08, 2016, 03:53:52 pm
content: Quote from: Fungus on August 08, 2016, 11:52:00 amIn that case: you can buy used 500MHz to 1GHz DSOs (Tektronix TDS500 or TDS700 series for example) oscilloscopes for less than $1000.

author: Fungus
author_rank: Super Contributor
timestamp: August 08, 2016, 04:16:40 pm
content: Quote from: nctnico on August 08, 2016, 03:53:52 pmThatwouldbe true - if they were on the list of options being argued over.

author: Muxr
author_rank: Super Contributor
timestamp: August 08, 2016, 04:23:31 pm
content: Quote from: nctnico on August 08, 2016, 03:53:52 pmI dunno that it's a terrible idea per se. Memory depth is pretty low on those though like 15Kpts? compared to Rigol's 24Mpts. Also those scopes are old now. And for your first scope you probably want something that may not be on its last legs. They also don't have the reparability of the old analog Tek scopes, but that's a whole other topic.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: August 08, 2016, 06:09:49 pm
content: Quote from: Muxr on August 08, 2016, 04:23:31 pm2nd hand is not limited to Tek. I've seen quite a few LeCroy WaveRunner2 LTs going for less than $1k, which come with bandwidths of 350Mhz to 1GHz, 1GSa/s+ sample rates (on each channel, i.e. no half-channel degradation) and with up to 8M memory, plus a ton of math and analysis functions. They're not even overly old (2001 to 2004) and thanks to Iwatsu's (the company who built them) excellent build quality are generall good for many years to come.

author: nctnico
author_rank: Super Contributor
timestamp: August 08, 2016, 06:23:44 pm
content: Quote from: Muxr on August 08, 2016, 04:23:31 pmRegarding the TDS500/700 series: The memory depth is more like 1Mpts on the older models! And FFT (up to 32kpts IIRC) with averaging of the results so you at least you can get a stable FFT result. But there are newer oscilloscopes out there for less than $1000 and many nice features except protocol decoding.

author: pascal_sweden
author_rank: Super Contributor
timestamp: August 08, 2016, 06:34:33 pm
content: Not all LeCroy / Iwatsu scopes are great though.Take for example the LeCroy Wavejet Touch 354:The menu consumes a considerable amount of the screen real estate, and it takes that space even when the menu is hidden:https://youtu.be/uDBuUI5GZ7Q?t=965Placement of the buttons is not done wisely:https://youtu.be/uDBuUI5GZ7Q?t=1392The update rate is very slow when making adjustments:https://youtu.be/uDBuUI5GZ7Q?t=1589The intensity grading is really poor:https://youtu.be/uDBuUI5GZ7Q?t=1626There is no decoding for I2C, SPI and UART:https://youtu.be/uDBuUI5GZ7Q?t=1834It almost defeats the purpose of having a 5000 USD whizbang scope!https://youtu.be/uDBuUI5GZ7Q?t=1870

author: Muxr
author_rank: Super Contributor
timestamp: August 08, 2016, 06:42:22 pm
content: Quote from: nctnico on August 08, 2016, 06:23:44 pmYeah, that's not bad.. Rigol's FFT is pretty weak. I like Wuerstchenhund's idea of looking at those LeCroy (Iwatsu) scopes, didn't realise they can be found for ~$1000.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: August 08, 2016, 06:47:49 pm
content: Quote from: pascal_sweden on August 08, 2016, 06:34:33 pmYeah well, it's an upper entry-level scope based on an Iwatsu design from around 2003, so yes, it's no racer. On the other hand it's exactly what certain large industrial customers want, which is why it is still in portfolio. Customers that want a robust, reliable and simple to use decent portable scope that is backed by great service.And now just for fun, compare the price of the 500Mhz WaveJet Touch and say a 500MHz Keysight DSOX3054T.

author: David Hess
author_rank: Super Contributor
timestamp: August 08, 2016, 06:48:55 pm
content: Quote from: Wuerstchenhund on August 08, 2016, 05:24:56 amA better comparison would be an old manual transmission VW bug with carburetor and points which is viable for basic transportation and eminently maintainable versus a modern vehicle which occasionally suffers firmware crashes and mysterious check engine notifications requiring dealer service.With care a working 100 MHz dual timebase Tektronix can be found in the US for $50 or a 2230 DSO for $100 but in Australia it will be better to go with a new cheapo Chinese DSO.That was not a deliberate rhyme; that is my story and I am sticking to it.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: August 08, 2016, 06:52:11 pm
content: Quote from: David Hess on August 08, 2016, 06:48:55 pmWell, my favorite comparison is still that the analog scope is the equivalent of measuring voltage with a light bulb

author: marmad
author_rank: Super Contributor
timestamp: August 08, 2016, 06:56:50 pm
content: Quote from: Muxr on August 07, 2016, 05:31:08 pmHave you used both DSOs? The DS2000 is about tenfold faster than the DS1000Z (it has a whole separate FPGA for doing post-processing). As someone that has owned the DS2000 for 4 years and then used the DS1000Z for several months, I found it almost unbearable to use for anything other than the simplest waveform viewing. Turn on virtuallyanyextra functions (especially when 4-channels are running) and the response of the DSO drops to a smail's crawl... it's terrible. Unless you need 4-channels almost exclusively (and most people don't: the majority of oscilloscopes produced have been 2 channels), I'd rather own a fast, 2-channel DSO that actually does all of the things it's supposed to do - and does them well(EDIT:except FFT - Rigoi's uniformly suck at that).QuoteOk, now I'm fairly certain you've never used the DS2000. Yet another big difference you didn't mention (aside from speed): the DS2000's decoding works really well (I use it all the time). It's fast and it decodes the entire memory, not just display memory. It also decodes while in segmented memory, which brings me to another huge difference between the two DSOs: segmented memory. The DS1000Z's implementation is a useless joke (it's basically the same crappy implementation as the old DS1000E series). The DS2000, OTOH, has real segmented memory capture with timestamps and analysis. They are worlds apart.Almost anyone that has used a DS2000 would then find it (as I did) almost painful to use a DS1000Z. They are not "cousins" - the DS2000 is an adult; the DS1000Z is a child.

author: Gyro
author_rank: Super Contributor
timestamp: August 08, 2016, 07:05:35 pm
content: Quote from: Wuerstchenhund on August 08, 2016, 06:52:11 pmYes, we are aware. Been there, done that one to death.

author: Muxr
author_rank: Super Contributor
timestamp: August 08, 2016, 07:08:24 pm
content: Quote from: marmad on August 08, 2016, 06:56:50 pmI have a DS2000 and I don't remember the serial decoding being done in memory. Also I remember DS2000 being pretty sluggish. I've been thinking of upgrading the firmware on it, so I will give it a spin. If you're right that's pretty nice.

author: marmad
author_rank: Super Contributor
timestamp: August 08, 2016, 07:36:49 pm
content: Quote from: Muxr on August 08, 2016, 07:08:24 pmIt's something they fully implemented a few years ago already.QuoteCompared to what? Surely you don't mean compared to the DS1000Z - it's not even close.

author: Muxr
author_rank: Super Contributor
timestamp: August 08, 2016, 07:39:34 pm
content: Quote from: marmad on August 08, 2016, 07:36:49 pmJust sluggish, as in not very pleasant to use in some menus, and even just basic things have input lag, although in general it's a good scope don't get me wrong, certainly usable and for the money great. My old HP 54610B is much more responsive than it (not even comparing it to my RTM 1054). I haven't used the DS1k.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: August 08, 2016, 07:53:04 pm
content: Quote from: Gyro on August 08, 2016, 07:05:35 pmGreat

author: marmad
author_rank: Super Contributor
timestamp: August 08, 2016, 08:06:53 pm
content: Quote from: Muxr on August 08, 2016, 07:39:34 pmWell, the fact that your HP is old is not really relevant; just because electronics get less expensive and some new or improved features (e.g. the DS2000 has 14,000x more memory than the 54610B), it doesn't mean all features are improved.QuoteTrust me: if you're complaining about the 'sluggishness' of the DS2k, you won't want to

author: Muxr
author_rank: Super Contributor
timestamp: August 08, 2016, 08:20:32 pm
content: Quote from: marmad on August 08, 2016, 08:06:53 pmDuly noted

author: Muxr
author_rank: Super Contributor
timestamp: August 08, 2016, 08:21:37 pm
content: Quote from: Wuerstchenhund on August 08, 2016, 06:52:11 pmThat intensity grading though

author: David Hess
author_rank: Super Contributor
timestamp: August 08, 2016, 09:33:36 pm
content: Quote from: Wuerstchenhund on August 08, 2016, 06:52:11 pmIt is more like a 2-dimentional magic eye tube with index grading for the 3rd dimension.As far as measuring voltage, my analog 7603 has no trouble making accurate voltage measurements to 4 digits ... using slideback techniques and an auxiliary voltmeter which is effectively built in.A normal voltmeter by itself cannot measure voltages over wide bandwidths but combining the two instruments allows something which neither can do alone and a DSO by itself cannot do either. How often do I actually do this? Occasionally but almost never where the extra accuracy over a DSO is needed.If someone needed an inexpensive entry level oscilloscope with high bandwidth, then I would recommend an older analog oscilloscope but in this case given that it is Australia where all the old American HP and Tektronix gear got poisoned by the native wildlife and bandwidth is not a consideration, even I say go with something cheap which means Chinese.While I have not gotten to evaluate one personally, my recommendation for a step up from the cheapo Chinese stuff would be one of the R&S HMO1202 series DSOs. I really like what I have seen about how they operate and how they are built. I wonder though if this should apply to all of the Hameg descended R&S DSOs.

author: rstofer
author_rank: Super Contributor
timestamp: August 08, 2016, 10:28:37 pm
content: Quote from: Wuerstchenhund on August 08, 2016, 05:24:56 amOP, you're in the wrong forum/web site if you think that anybody, other than me, will recommend an analog scope. OTOH, my well worn, $200, Tektronix 485 has a bandwidth of 350 MHz, far higher than what I would be willing to pay for a digital scope.Every thing I have done for the last 12 years since I retired has been with that 485. There was nothing I needed to do that I couldn't do with that scope and, really, there still isn't. But, my, the digitals sure look pretty - and all those numbers! Remember this: Everything you see on a digital scope is reconstituted after some arbitrary number of samples are taken and the data manipulated by a C programmer. Do the sample hit the important bits? Beats me! The programmers can't even get the GUI right, why do I believe their calculations?The downside to analog scopes is that, generally, they don't have a one-shot mode. That is the ONLY advantage to the digital scope. Oh, sure, the measurements are neat but we've been doing measurements for generations before digital came along. Somehow, we got it done... But single shot is truly useful when trying to decode an SPI transaction.For the low frequencies involved with embedded projects or robotics, there really is no need for anything beyond 100 MHz and my 350 MHz is overkill. But I always liked the Tek 4xx series scopes and I just bought what I wanted. I remember back to the days with the 455 was king and mainframes really were 'big iron'. Most of the field service guys had the 60 MHz 455.I wouldn't recommend buying an analog scope as a backup to the 1054Z until you get a lot farther along and have bought everything else. It just isn't that important. OTOH, the old Tektronix scopes were very high quality and very reliable. Not this Chinese crap!

author: David Hess
author_rank: Super Contributor
timestamp: August 09, 2016, 12:32:20 am
content: Quote from: rstofer on August 08, 2016, 10:28:37 pmI can say the same thing about my first 2230 which I picked up for $60 which is far less than I was willing to pay for a modern 100 MHz DSO. When I decided that I needed 4 channels, I picked up another 2230 for $80.QuoteMy 2230s are also DSOs so they have no problems with single shot acquisitions.But I recognize that people in the US have a big advantage in accessing vintage test equipment at low prices and many users are not technically oriented enough at least initially to maintain an old instrument no matter how much they might learn from the experience.The photo below showing warm up drift was taken after I picked up a 2232 to keep my 2230s company. The displays are configured to show a 2k (2048 point) record length on a 1k (1024) point wide display. Yes, they cannot decode SPI or make automatic measurements but the cursor measurements work fine and 2 GS/s equivalent time sampling is completely adequate for 100 MHz signal integrity testing which often comes down to looking for something weird.

author: rstofer
author_rank: Super Contributor
timestamp: August 09, 2016, 01:01:34 am
content: Besides, they LOOK like oscilloscopes!

author: Neganur
author_rank: Unknown
timestamp: August 09, 2016, 05:17:17 am
content: Quote from: rstofer on August 07, 2016, 05:44:44 pmFor the sake of argument, a person from Keysight called my msox3104A an entry-level scope.That stung a bit.I think the rigol is excellent for what it costs.

author: Berni
author_rank: Super Contributor
timestamp: August 09, 2016, 05:31:24 am
content: Quote from: Neganur on August 09, 2016, 05:17:17 amWell to be fair the x2000/x3000 scopes are technically the "crappiest" scopes that Keysight makes right now. Not that they are bad scopes (I use one regularly and its nice) and they can certainly beat cheap Rigols in areas, The x6000 is what is considered mid-range at Keysight (Tho what you mostly get is more bandwith pretty much, not a lot in the way of features).

author: vk6zgo
author_rank: Super Contributor
timestamp: August 09, 2016, 06:02:13 am
content: Quote from: David Hess on August 08, 2016, 06:48:55 pmA DS1054Z at US$400,at current exchange rates equates to $A526,before freight!The halcyon days of the "mighty Oz"coming in at 1.3 x the US $ are long gone.Buying a DS1054Z or similar from an Australian agent won't leave you much change from $A700.Chinese with freight isn't that much better.Unfortunately local eBay sellers see these sort of prices & think they can sell their old 100Mhz analog Teks for $A300 plus!"Tell 'em they're dreaming!!"

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: August 09, 2016, 09:36:35 am
content: Quote from: Neganur on August 09, 2016, 05:17:17 amWell, the DSOX/MSOX3104A*is*an entry-level scope (actually, it's upper entry-level)QuoteWhy? What did you think a 1GHz 4GSa/s embedded platform scope with 4Mpts of sample memory is, really? High-end?

author: Fungus
author_rank: Super Contributor
timestamp: August 09, 2016, 09:39:16 am
content: Quote from: Muxr on August 08, 2016, 06:42:22 pmOr.... if FFT is very important and you've got $1000 to spend you can get a $400 Rigol and a proper spectrum analyzer. A $600 spectrum analyzer will totally destroy any general-purpose oscilloscope in that price range.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: August 09, 2016, 10:32:52 am
content: Quote from: Fungus on August 09, 2016, 09:39:16 amYes, and the $600 SA will very likely be 30yrs old, huge, weigh nearly a ton, and draw a lot of power (and produce a lot of noise doing so). It will also be pretty useless for signals below 9kHz (i.e. audio), signals with a BW >5MHz (which is the max RBW on many old SAs) and will likely need additional protection so that some DC bias doesn't kill the input stage.FFT on a decent scope on the other hand has no problems dealing with audio or DC bias, and it can produce a coherent spectrum for large BW signals.

author: pascal_sweden
author_rank: Super Contributor
timestamp: August 09, 2016, 10:43:23 am
content: Any computer sound card (Adlib, Roland, SoundBlaster) dating from the late eighties, begin nineties can reach up to 44-48 KHz. So why would you even consider to use a SA for audio work?You even had these professional sound cards available for the Commodore Amiga:AD516 from Sunrize Industries:http://amiga.resource.cx/exp/ad516Toccata 16 from MacroSystem:http://amiga.resource.cx/exp/toccataIs 16-bit, 44-48 KHz not considered high fidelity these days?Or do some of you guys have 48-bit ears and can hear up to 1 Hz Resolution Bandwidth? =)

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: August 09, 2016, 11:00:06 am
content: Quote from: pascal_sweden on August 09, 2016, 10:43:23 amThe point was that FFT in a scope can do audio, and in many cases that might be enough.

author: JPortici
author_rank: Super Contributor
timestamp: August 09, 2016, 11:08:11 am
content: Quote from: pascal_sweden on August 09, 2016, 10:43:23 amTrue, though it can't go down to DCunless you get a DC coupled audio interface, like most if not all MOTUs

author: Muxr
author_rank: Super Contributor
timestamp: August 09, 2016, 11:16:40 am
content: Quote from: pascal_sweden on August 09, 2016, 10:43:23 amIt's about the workflow. Say a sound card can do everything my SA can.. it's still different software and entirely different workflow I have to use to measure a certain band of frequencies, where I would just rather use what I use for all my SA measurements.Also the confidence level. How do I know the sound card I am using doesn't have jitter or noise issues?

author: pascal_sweden
author_rank: Super Contributor
timestamp: August 09, 2016, 11:41:25 am
content: Can you give some examples of the audio measurements which you are doing, and for which projects you do them?

author: Muxr
author_rank: Super Contributor
timestamp: August 09, 2016, 12:20:48 pm
content: Quote from: pascal_sweden on August 09, 2016, 11:41:25 amNot sure how relevant that is to my workflow argument. If I already have an SA for non audio frequencies I'd like to be able to use the same instrument at audio frequencies.edit:But I am mainly looking at testing filters, noise floor and distortion measurements. If you really want to know, I am working on configuration via sound and light. For instance using high frequency audio (stuff only dogs can hear) in your smartphone to configure your electronic microcontroller project.

author: Fungus
author_rank: Super Contributor
timestamp: August 09, 2016, 12:37:40 pm
content: Quote from: Muxr on August 09, 2016, 12:20:48 pmCan your smartphone speaker/DAC produce those frequencies?(....at any useful volume)

author: Muxr
author_rank: Super Contributor
timestamp: August 09, 2016, 12:40:48 pm
content: Quote from: Fungus on August 09, 2016, 12:37:40 pmYes there is a commercial product that's already doing this, but the name escapes me right now (will update if I rememeber it). They use this method to configure wifi networking on a keyboardless device, via your smartphone.

author: Fungus
author_rank: Super Contributor
timestamp: August 09, 2016, 12:49:57 pm
content: Quote from: Muxr on August 09, 2016, 12:40:48 pmWouldn't bluetooth be easier?

author: Muxr
author_rank: Super Contributor
timestamp: August 09, 2016, 12:50:48 pm
content: Quote from: Fungus on August 09, 2016, 12:49:57 pmWhat's the fun in that?

author: Fungus
author_rank: Super Contributor
timestamp: August 09, 2016, 12:53:26 pm
content: Quote from: Muxr on August 09, 2016, 12:50:48 pmWhen you're done you can get a job working at uBeam.

author: Muxr
author_rank: Super Contributor
timestamp: August 09, 2016, 12:55:41 pm
content: Quote from: Fungus on August 09, 2016, 12:53:26 pmNo thanks.

author: Loboscope
author_rank: Regular Contributor
timestamp: August 09, 2016, 01:06:25 pm
content: For Audio measurements I would recommend "hpw-works" [http://hpw-works.com/index.php].It can not only show Spectrums but can measure anything relevant to audio. For really effective and reliable measurements You have to combine it with a really professional interface like for example RME Babyface or similar. The possible sample-range of hpw-works exceeds the 192 KHz-barrier of most sond-cards, so if you will find an interface with more than 192 KHz you can go even far into the ultrasonic-range. It is even possible to connect hpw-works simultaneously with more than one interface.

author: pascal_sweden
author_rank: Super Contributor
timestamp: August 09, 2016, 04:28:42 pm
content: Quote from: Muxr on August 09, 2016, 12:20:48 pmThere was a company at the IBC tradeshow in Amsterdam that had a product built around that technology about 2 or 3 years ago if I recall correctly.

author: Muxr
author_rank: Super Contributor
timestamp: August 09, 2016, 04:33:29 pm
content: Quote from: pascal_sweden on August 09, 2016, 04:28:42 pmMy main motivation for it is to hopefully make it work and open source it for the hobbyist community. The goal is for it to be cheaper than alternatives (bluetooth) but also easier to deploy. Bluetooth generally requires a smartphone App.. This could work via web browser.I feel like the initial configuration is the biggest barrier to entry for wider adoption of open, hobbyist "IOT" (even though I don't like that term) devices...sorry for the thread deraillement

author: David Hess
author_rank: Super Contributor
timestamp: August 10, 2016, 05:58:05 am
content: Quote from: pascal_sweden on August 09, 2016, 10:43:23 amMany or most do not extend past about 20 kHz no matter what sample rate they support and none go to DC. Here is an old review of some suitable sound cards:http://www.clarisonus.com/Research%20Reports/RR001-SoundCardEval/RR001-PCsoundCards.html

author: bitseeker
author_rank: Super Contributor
timestamp: August 11, 2016, 04:35:14 am
content: Thanks for that report link, David. Very interesting. I have an M-Audio Delta 66 (24-bit & 96kHz sampling, input: +/-0.4 dB from 22Hz to 40kHz, 4 channels), which I haven't used in a while. At least on paper, it should perform better than the 2496. I'll have to check out the software SA sometime. It'd probably work well enough for tweaking the minimum distortion level on the sine output of my analog function generator.

author: Berni
author_rank: Super Contributor
timestamp: August 11, 2016, 05:10:40 am
content: I built my own Audio Analyzer from scratch by using the best spec audio ADC that TI makes and attaching it to a MCU that makes it in to a USB sound card. The important part is that the sound card uses the new Async USB audio 2.0 standard. That way the computer is forced to follow the pace of the ADCs clock and so you don't get any clock jitter or resampling crap in the signal.On the PC side i just use Visual Analyzer to do FFT and all that on it. It can see signals as small as -130dB and i measured a THD of 0.0002%. I would love to turn this is in to a DIY scope like instrument with a screen but that would take a lot of work.

author: bitseeker
author_rank: Super Contributor
timestamp: August 11, 2016, 05:18:49 am
content: That sounds very cool, Berni.

author: borjam
author_rank: Unknown
timestamp: August 11, 2016, 07:42:33 am
content: Quote from: David Hess on August 10, 2016, 05:58:05 amAlthough not cheap at all, Metric Halo's ULN-8 is DC coupled. The problem is, you are paying for a lot of functionality you don't need. Other professional audio interfaces (Peecee "cards" do not usually belong in that cathegory) can be suitable as well, and as far as I know most of the professional units can get useful signals to Nyquist/2. A friend who was working with 30 KHz ultrasounds used a quite cheap M-Audio interface and it indeed produced good quality signals.The pro manufacturers (pardon me if I omit some) are Metric Halo (expensive), RME (expensive), MOTU (affordable to expensive), M-Audio (affordable), Edirol (affordable), Tascam (affordable to expensive). I don't know which of them are DC coupled, though. I know (the designer told us) that the ULN-8 and LIO-8 from MH are DC coupled.And regarding measurement software, Metric Halo sells a very good audio measurement software called SpectraFoo. It's designed mostly for sound engineers (both live and studio applications) and apart from a good spectrum analysis it can do distortion measurements and plenty other things.A cheaper alternative, although simpler, is Spectre from Audiofile Engineering. Also for Mac OS X. Both Spectre and SpectraFoo work with any Core Audio device.

author: bitseeker
author_rank: Super Contributor
timestamp: August 11, 2016, 09:32:32 pm
content: borjam, do you happen to know which M-Audio interface your friend used?

author: aandrew
author_rank: Frequent Contributor
timestamp: August 12, 2016, 01:31:58 am
content: Quote from: rstofer on August 07, 2016, 05:44:44 pmI would counter that there isn't a scope under $5000 that can even approach that kind of problem.Hell, I design systems with PCIe, SATA and USB3 and it's *very* infrequent that I need a scope with that kind of capability. A recent contract had us scratching our heads trying to find out why a PCIe link would not come up. LeCroy dropped off one of their top-end MSOs. With all the bells and whistles on that demo unit the MSRP was almost $140k!Was it a *damn* nice scope? Oh yes. It would directly decode PCIe transactions from looking at the TX/RX lanes. Is it something I'd ever buy for myself? Not a chance.QuoteCouldn't agree more. I bought a Hantek MSO5074FG. It's got its warts but it's a decent scope for the price, and if I can ever get the time to hack on it, I can hack on it. Meanwhile I continue to scour ebay for a good used LeCroy, Tek or Agilent MSO with at least 2GHz bandwidth... *drools*

author: Berni
author_rank: Super Contributor
timestamp: August 12, 2016, 05:31:02 am
content: Quote from: aandrew on August 12, 2016, 01:31:58 amWell i bought a like new condition 2.5GHz Agilent DSO9000H for 6 grand on ebay that turned out to be a 4GHz scope after some software fiddling, and after some more unlocked all the options. It was because Keysight discontinued the H series and dumped like 10 or more of them on ebay for cheep, later i found that they are the same hardware as the A series that still sells today for high 5 digit dollars.But beware that it doesn't stop here, you also need to spend another grand or more on fancy active probes to make use of it as the passive stuff stops at 500MHz and has so much capacitance that it screws up your signal under test.

author: borjam
author_rank: Unknown
timestamp: August 17, 2016, 02:54:32 pm
content: Quote from: bitseeker on August 11, 2016, 09:32:32 pmI don't remember (I'll try to find out) but this classic Edirol interface (UA-25) states 20 Hz - 40 KHz +0 -2 dB @96 KHz.https://www.roland.com/us/products/ua-25/specifications/Although discontinued it's pretty easy to find second hand.

author: cncjerry
author_rank: Unknown
timestamp: August 17, 2016, 08:57:34 pm
content: Quote from: aandrew on August 12, 2016, 01:31:58 amSounds likes a challenge! What would the objective be? Determine if there is HF modulation or not on a 1G signal using a scope that cost less than $500? I can do it on my sub $500 SA, I wonder if a TDS784 can do it? I paid $400 for mine with 6 probes. I'm out of the country or would wire it up. Let's put more parameters on the test, maybe 1G signal with 10Mhz FM modulation?

author: Muxr
author_rank: Super Contributor
timestamp: August 17, 2016, 09:17:43 pm
content: Quote from: aandrew on August 12, 2016, 01:31:58 amI sort of gave up on that idea mainly because those older multi Ghz scopes I could afford aren't really good day to day bench scopes. They tend to be huge, loud and take forever to boot. Also their inputs tend to be more fragile. Not to mention you need equally expensive probes for those frequencies as well.I am pretty happy with my R&S RTM 1054.. it's plenty of scope for my needs and it didn't break the bank.

author: Berni
author_rank: Super Contributor
timestamp: August 18, 2016, 05:39:54 am
content: Quote from: Muxr on August 17, 2016, 09:17:43 pmI have to agree on that. As soon as it is a scope that runs a desktop OS it tends to stop being a good every day scope. Sure there is all the performance in there but it boots slowly(not only the os, but often the scope app too), usually is noisy and uses a lot of power. Also often you can't set up all of the scope trough the front panel buttons, for some stuff you need a touchscreen or mouse to navigate extra menus.I certainly had lots of cases where a high performance scope was incredibly helpful, but most often i use my 300MHz MSO6000 because it gets the job done faster.So if you are looking to get a high end scope, you better also have some lowend lightweight scope for the case where you just want to quickly check if a 5MHz clock is running on a board or something. There is a reason they make hammers in different sizes, they are essentially the same tool but for different use cases.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: August 18, 2016, 07:53:37 am
content: Quote from: Berni on August 18, 2016, 05:39:54 amNot necessarily. Booting can be pretty fast once the standard slow low rpm hard drive that is commonly found in Windows based scopes has been replaced with a decent SSD.And it's not that embedded platform scopes are necessarily fast, too. For example, my new Tek MDO3000 take around as long to boot as my old LeCroy WavePro 7300A running WindowsXP.QuoteYes, but that is mostly because Windows scopes tend to be mid-range or high-end scopes with very fast ADCs that produce a ton of heat, and if you replaced the PC processing backend with an embedded low-power backend as found in the typical low-end scope then it would still be noisy and suck a lot of power.QuoteAnd touchscreen (which is used on an increasing number of entry-level scopes like the Keysight DSOX3kT) is bad because? How else would you want to control all the functions that can be found in a newer high-end scope? Buttons?I do agree that an UI that requires a mouse isn't great for using on a bench, but it's mostly HP/Agilent that relied on it (although the UI on newer Keysight Infiniiums scopes has improved a lot over the old Infiniium 54800 UI). Tek had a somewhat decent touch UI on their Windows-based scopes, and LeCroy had their MAUI which is was designed for touch right from the start.QuoteAs someone who uses a high end scope pretty much every day (at work and at homeI have to disagree here. I find it's much easier to just do the measurement with the high-end scope than fetching a entry-level scope, powering it up and do the measurement with it. Plus quite often even simple problems turn out to be rather more complex, in which case the tools available on the high end scope make life so much easier, even if it's just a 50MHz signal.However, I do have to admit that it very much depends on the scope in question. Newer Keysights like the DSO-S are great, they boot fast and have a decent an easy to use touch UI. LeCroy mid-range (WaveSurfer) and high-end (WaveRunner, WavePro) scopes also make great general purpose scopes. Older Infiniiums (especially pre-DSO9k models), not so much, simply because of their poor mouse-driven UI and various hardware limitations (i.e. sample memory size drop at higher sample rates) in some models. Tek Windows scopes, while having a somewhat decent UI, are generally slow like wading through molasses in pretty much everything, and tend to lock up when under load. They aren't exactly a joy to use but that is pretty independent of the complexity of the measurement.Scope inputs aren't really a problem with scopes with a BW of up to 3-8 Ghz, which are usually equipped with BNC or BNC-compatible connectors and have switchable 50ohms/1M inputs. Only very high bandwidth scopes come with non-BNC low-Z (50ohms) inputs only, in which case you'd need an expensive high-z adapter to be able to use a standard passive probe.So it really depends on what your scope is.

author: Muxr
author_rank: Super Contributor
timestamp: August 18, 2016, 01:21:21 pm
content: Quote from: Wuerstchenhund on August 18, 2016, 07:53:37 amThis is true. I was mostly thinking of the older Infiniums in my comment. I am sure newer 3-8Ghz scopes are sweet, but they also cost more than I am willing to spend. Everyone's needs and priorities are different. For me personally my next big item purchase is a pick and place machine.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: August 18, 2016, 02:37:14 pm
content: Quote from: Muxr on August 18, 2016, 01:21:21 pmYes, if you focus on Agilent/Keysight. It took averylong time until Agilent managed to do a Windows scope properly (the DSO9k is the first one that was decent, despite using the same poor UI as previous scopes), and only recent models have improved enough to make decent every-day scopes. The older Infiniiums also weren't particularly capable (limited options, mostly for some special purpose task like compliance testing).The same isn't true for LeCroy scopes, though. Leaving the older non-Windows scopes out for now, all their Windows scopes (which are all either mid-range or high-end models) make great every-day scopes. Unlike the old Infiniiums, they do pretty much everything a good entry-level scope does, and a lot more. Every scope can do serial decode for a wide range of standards (which includes even niche standards like SpaceWire), there are a wide range of analysis options for pretty anything, and they don't suffer from silly architectural limitations like the drastic reduction of sample memory at higher sample rates as some of the older Infiniiums do. They are easy to use and even the first ones from 2001/2002 are still supported by the bi-yearly X-Stream software updates which makes them compatible with the latest probes which means you can pretty much use any ProBus probe that has been made since 1994 or so (Agilent/Keysight has not only artificially limited probe compatibility between InfiniiVision and Infiniium scopes, once a scope is out of support then software updates stop, and most often they have stopped long before that).Fast ADCs still get very hot, and very hot stuff needs a lot of cooling, which means it more noise and more power draw. Unfoortunately for now there's no way around that. If you can live with the noise and higher power draw however, there are quite a few scopes, even on the 2nd hand market, that offer large BW and sophisticated analysis tools while making great every-day scopes.QuoteNiceBut you're right of course, individual needs and priorities do vary.I just wanted to show that you don't really need a second every-day scope if you get yourself a more advanced scope.

author: rstofer
author_rank: Super Contributor
timestamp: August 18, 2016, 02:53:04 pm
content: Quote from: Muxr on August 17, 2016, 09:17:43 pm$3500 for a 'seller refurbished' unit? That's not my idea of an 'entry level' scope. Looks pretty nice though...http://www.ebay.com/itm/Rohde-Schwarz-RTM-1054-4-Ch-500-MHz-5-GSa-s-Digital-Oscilloscope-w-Accys-/271835203486List price over $10k? Clearly not an 'entry level' scope:https://www.conres.com/test-equipment/product/rohde-schwarz-rtm1054-500mhz-4-channel-digital-oscilloscope/We're talking $400 scopes, maybe $1000 scopes - 'entry level'

author: Muxr
author_rank: Super Contributor
timestamp: August 18, 2016, 03:24:01 pm
content: Quote from: rstofer on August 18, 2016, 02:53:04 pmI got lucky. Thanks to Wuerstchenhund in fact.. he mentioned them being available on ebay for $2000 in one of his posts while back. Someone was liquidating a lot of 10 or so. So I snatched one. They were used but looked in brand new condition, mine came with all the probes and accesories looking brand new.But you're right not exactly entry level, although close in price.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: August 19, 2016, 06:33:37 am
content: Quote from: rstofer on August 18, 2016, 02:53:04 pmYou are right, the RTM1000 isn't entry-level, it's actually R&S' lower mid-range scope series (the R&S entry level is made up of Hameg devices).And yes, $3.5k for a "seller refurbished" (whatever that should mean) unit is ludicrous, but as Mux said a while ago there was a dealer who sold ten or so for below $2k, all in pretty much pristine condition and with all accessories and probes (still sealed) included.And for $2k it's a really nice scope and one of the only few that can actually do X/Y/Z operation (i.e. brightness modulation, something that's usually limited to analog scopes)QuoteThe Entry Level segment goes much further than $1000 (i.e. the Keysight DSOX3000T which is an upper entry-level scope that starts at some $3k or so) and can easily exceed $5k.What you probably mean are bottom-of-the-barrel scopes, which is an appropriate term for scopes in the sub-$1k price class.

author: Jwalling
author_rank: Unknown
timestamp: August 19, 2016, 09:52:11 am
content: Quote from: Wuerstchenhund on August 19, 2016, 06:33:37 amYep.Jay

author: Fungus
author_rank: Super Contributor
timestamp: August 19, 2016, 09:59:17 am
content: Quote from: Jwalling on August 19, 2016, 09:52:11 amDon't complain: They'd have been "mid-range" not too long ago.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: August 19, 2016, 10:18:51 am
content: Quote from: Fungus on August 19, 2016, 09:59:17 amActually, they would have been mid-range in the mid '90s. Which only counts as "not too long ago" in glacial terms

author: marmad
author_rank: Super Contributor
timestamp: August 19, 2016, 10:51:28 am
content: Quote from: Wuerstchenhund on August 19, 2016, 10:18:51 amActually, similar to the fact that light-year is a term of distance, not time, glacial (at least in English) is a term used to denote speed, not time

author: Fungus
author_rank: Super Contributor
timestamp: August 19, 2016, 10:53:00 am
content: Quote from: Wuerstchenhund on August 19, 2016, 10:18:51 amI guess it depends on what you class as "mid-range".If the "high-end" includes things like this:Then yes, they'd still be "low-end" not too long ago.The point is: Go back 5-10 years and not many people would have paid for a brand new, 100MHz, 4-channel DSOfor home use and with their own money.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: August 19, 2016, 11:00:53 am
content: Quote from: marmad on August 19, 2016, 10:51:28 amI'm sorry but that is wrong. 'Glacial' can refer to both speed (i.e. Glacial Speed) and time (Glacial Period).https://en.wikipedia.org/wiki/Glacial_periodA glacial period (alternatively glacial or glaciation) is aninterval of time(thousands of years) within an ice age that is marked by colder temperatures and glacier advances.Knowing is half the battle

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: August 19, 2016, 11:23:20 am
content: Quote from: Fungus on August 19, 2016, 10:53:00 amNo, it does not "depend" on 'if' or 'when' or what you feel like should be included or what not, the T&M market is and has been for a long time pretty solidly categorized. And by that standard today's bottom-of-the-barrel scopes would have been mid-range in the mid-'90s. Don't forget that the progress in these scopes wasn't in capabilities, the real progress in that category is the low price.BTW: that scope in the video, while being a high-end scope, is hardly the most expensive. In fact, the DSA91304A (which is a variant of the Infiniium 90k, which until a while ago was my day to day work scope, sold as signal analyzer) isn't (and wasn't) really far up the ladder in terms of high end scopes.QuoteWho knows, maybe that's true, maybe not. I don't know (I have no sales figures for sales to consumers or B-brand in general) and you don't know either. Fact is that many hobbyists have bought scopes in the past. Back in the old days the Rigol equivalent would have been something like that:But it doesn't make current bottom-of-the-barrel scopes any more "mid-range". They still are what they are, the cheapest (reasonable) scopes money can buy.

author: marmad
author_rank: Super Contributor
timestamp: August 19, 2016, 11:30:26 am
content: Quote from: Wuerstchenhund on August 19, 2016, 11:00:53 amAhh... you want to quibble about whether it was technically correct, after a native English speaker tells you it reads assilly-soundingawkward*. Fair enough; that's typical engineer-behavior - especially on this forumIn any case, IMO, 20 years ago is "not too long ago" by human standards - so there's that as well.*EDIT:You used the word in the context of an adjective (i.e. denoting speed [or temperature or produced or caused by glaciers]), not as a noun (i.e. denoting a period of time). For example, it's not "...in day terms" - it would be either "...in daily terms" or "in terms of days...", etc.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: August 19, 2016, 03:58:09 pm
content: Quote from: marmad on August 19, 2016, 11:30:26 amDon't take this the wrong way, but frankly, I don't really care if you're a "native English speaker" (what English? British, American, Canadian, Aussie, NZ? What region? I have no idea what variant of English is spoken in Antarctica; besides I've met my fair share of "native speakers" in various languages that didn't exactly demonstrate a stellar command of their mother tongue), or if you think it "sounds silly". It might well be that in your part of the world "glacial" is only used in regard to speed. But it isn't in the parts of the world I move around, and clearly isn't in a scientific context, so here you go.And it obviously wasn't beyond your intellect to understand the meaning.QuoteThat, again, is merely your opinion, to which you're certainly entitled to. But it's just that, your opinion.QuoteI used 'glacial' as an adjective because it is. That doesn't mean it's wrong. It's quite commonly used in scientific literature, i.e. in 'Up in Smoke? Latin America and the Caribbean' by Andrew Simms and Hannah Reid, p 18:"In glacial terms, 60 years is normally a blink in time.[..]". Or in 'Finding Time For The Old Age - A History Of Paleolithic Archaeology and Quaternary Geology in Britain, 1860-1960' by Anne O'Connor, p. 270:"... a distinctive stone tool might decide the age (in glacial terms) of a boulder clay...". And these are just two examples where the expression 'glacial terms' is used in regard to time, not speed.As I said, knowledge is half the battleSo, can we go back to topic?

author: marmad
author_rank: Super Contributor
timestamp: August 19, 2016, 05:11:25 pm
content: Quote from: Wuerstchenhund on August 19, 2016, 03:58:09 pmI guess that depends on how one defines "quite commonly". When I Google the phrase "in glacial terms", 9 out of 10 of the hits on the first page (aside from, surprise, one of the quotes you posted) are the correct use of the adjective, 'glacial'. I'm guessing the percentage of the rest of the hits would be roughly equivalent, and thus "occasionally" would be, in my "part of the world", a more accurate way to describe it's usage. Nonetheless, even occasional usage in scientific literature does not mean the usage is correct. Can you post a link toanyreference that describes "glacial" (the adjective - not the noun) as meaning time-related?But honestly, the original response was done mainly in jest as a response to your typically pedantic response to Fungus' use of the phrase "not long ago". Merely your opinion, of course, to which you're certainly entitled. But it's just that, your opinion.Your responses, of course, have not deviated from the norm.QuoteClearly it's not.QuoteWhich was what? How wonderful high end scopes are?

author: nfmax
author_rank: Super Contributor
timestamp: August 19, 2016, 07:54:07 pm
content: Reverting to the original topic for a moment (sorry!) it is astonishing to me just how much scope you can get for a hobby budget today. I ceased to be professionally involved 'hands on' with electronics about 2005, and up to that time I had never regularly used a scope with as much capability as the Rigol DS1054Z, with the sole exception of bandwidth. Assuming it is reliable enough, and the firmware is solid enough, it should provide everything you need for years of experimentation and learning. Treat it's limitations a challenge to your ingenuity - search for a non-obvious way of making the measurement. You have the luxury of time to ponder different approaches, which the professional doesn't. That's one reason why we are so demanding of our tools.While the Rigol looks to be the current best buy, there are plenty of alternatives around, so keep an eye open for bargains! Almost the only thing I wouldn't compromise on is the number of channels - 4 ismuchbetter than 2. And don't neglect the usefulness of an external trigger input. Bandwidth needs to be 50MHz at least, the more the better. Serial decoding, while very handy, is not essential IMHO unless you are trying to debug someone else's software. Measurements are also very handy and they all have them these days. A big screen is better than a small screen, even with the same number of pixels. Ensure it's not too big for the space you have available, and that you can live with the fan noise.Finally,take care of your scope probes, and keep them properly calibrated!

author: David Hess
author_rank: Super Contributor
timestamp: August 19, 2016, 09:54:35 pm
content: Quote from: nfmax on August 19, 2016, 07:54:07 pmUm, which is it? 4 channel oscilloscopes with external trigger inputs are very rare. If you look for one with both, your options will be very limited.

author: nctnico
author_rank: Super Contributor
timestamp: August 19, 2016, 10:29:21 pm
content: Quote from: David Hess on August 19, 2016, 09:54:35 pmAn MSO has 8 to 16 external trigger inputs!

author: tautech
author_rank: Super Contributor
timestamp: August 19, 2016, 10:44:52 pm
content: Quote from: nctnico on August 19, 2016, 10:29:21 pmFollowing on....SDS1000X+ series.....2 ch + Ext Trig + 16 Ch LA = 19 channels.As previously linked:http://www.siglentamerica.com/pdxx.aspx?id=4688&T=2&tid=1

author: Fungus
author_rank: Super Contributor
timestamp: August 20, 2016, 02:31:25 am
content: Quote from: tautech on August 19, 2016, 10:44:52 pm...and only 2.5x the price of a DS1054Z (and that'swiththe current special offer of free serial decoders - 3x the price otherwise).

author: tautech
author_rank: Super Contributor
timestamp: August 20, 2016, 06:11:40 am
content: Quote from: Fungus on August 20, 2016, 02:31:25 amOh, and SDS1000X series come with a full BW true 500 uV range, dismiss that as not worth having.

author: David Hess
author_rank: Super Contributor
timestamp: August 20, 2016, 07:11:03 am
content: Quote from: tautech on August 19, 2016, 10:44:52 pmSo my ancient 2440 has 2 channels + 2 external trigger channels (to support separate A and B trigger inputs) + 17 channels on the word recognizer which can be triggered on for 21 channels.Some old analog oscilloscopes like the Tektronix 7000 series can be configured with 4 vertical channels and 4 external trigger channels but I cannot imagine a realistic use for that many external trigger inputs.Is that 500uV/div sensitivity on the SDS1000X actually usable at full bandwidth or does noise prevent it? Siglent naturally give no noise specifications which is what I would expect if they are hiding the actual performance.

author: tautech
author_rank: Super Contributor
timestamp: August 20, 2016, 07:50:13 am
content: Quote from: David Hess on August 20, 2016, 07:11:03 am2 images borrowed from 2 posts by rf-loop that should answer that ^^^https://www.eevblog.com/forum/testgear/siglent-sds1000x-series-oscilloscopes/msg825532/#msg825532https://www.eevblog.com/forum/testgear/siglent-sds1000x-series-oscilloscopes/msg825633/#msg825633Baseline noise, no signal. Full BW both scopes @ 500uV/div.rf-loop said:Quote

author: tautech
author_rank: Super Contributor
timestamp: August 20, 2016, 07:53:04 am
content: Quote from: David Hess on August 20, 2016, 07:11:03 amSimilar can be done with a SDS2*04X, 4 ch + Ext trig + 16 LA channels = 21 channels

author: rf-loop
author_rank: Super Contributor
timestamp: August 20, 2016, 08:04:37 am
content: Quote from: David Hess on August 20, 2016, 07:11:03 amWhat is purpose for this kind of claim? Hiding what?Datasheet tell this, so it is still quite limited information but better than nothing:NoiseST-DEV </=0.7 division (<1 mV/div)ST-DEV </=0.3 division(<2 mV/div)ST-DEV </=0.2 division(>/=2 mV/div)*forum do not accept normal less or equal symbol (really??) so I use this </="...actually usable at full bandwidth...?"I do not know how usable, it depends needs. But BW is full and -3dB well over 200MHz.Edit: tautech was first so only add this comment.So or so but 1M ohm impedance >200MHz front end have noise. (If change front "impedance" to 50ohm it nearly do not change much because front end itself is still 1Mohm circuit) 500uV in 50ohm system is bit different what 500uV is on 1Mohm system. So or so but in reality this is what it is.Original image from SDS1202X is not from noise tests, it is just from level test (it may also include square wave source noise but it is clear that SDS1202X front end noise is dominating.

author: rf-loop
author_rank: Super Contributor
timestamp: August 20, 2016, 08:21:16 am
content: Quote from: tautech on August 20, 2016, 06:11:40 amBtw, Rigol DS1054Z have only 5mV/div true sensitivity. Ten times less.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: August 20, 2016, 08:52:15 am
content: Quote from: rf-loop on August 20, 2016, 08:04:37 amJust use underlining, i.e.<,>or+

author: rf-loop
author_rank: Super Contributor
timestamp: August 20, 2016, 09:49:19 am
content: Quote from: Fungus on August 20, 2016, 02:31:25 am2.4x ? Really? Why these claims without any connection to reality.Here all prices VAT 0Rigol MSO1104Z-SBatronix Eur 999,-Siglent SDS1102X+Batronix Eur 719,-MSO functions:Siglent SDS-1000X-16LA (license alone)Batronix Eur 115,-Siglent SPL1016 (probe alone)Batronix Eur 189,-Total: Eur 1023,-1023/999= 1.024 what is bit different as your claim 2.4.Compare these images.Note also that in real life images are not same size at all.Do you see what is around 2.4 times more or something like, perhaps your 2.4 come from this?Yes, with Rigol you get nearly 2.5 times more... with lower price.NOTE: Rigol display is not same size. S:8", R:7".Here relative size in real life.

author: JPortici
author_rank: Super Contributor
timestamp: August 20, 2016, 10:05:23 am
content: Quote from: rf-loop on August 20, 2016, 09:49:19 amHAHAHA YOU ARE WRONGHA YOU MUST COMPARE WITH THE BASE MODEL BECAUSE EVERYBODY HACK IT ANYWAYor simillar crapdon't waste time reasoning with someone immune to reason

author: Fungus
author_rank: Super Contributor
timestamp: August 20, 2016, 10:09:36 am
content: Quote from: tautech on August 20, 2016, 06:11:40 amHuh?I'm not sure if you're saying that:a) A scope that costs 3x the price shouldn't be any betteror that:b) You expect a $400 'scope to haveeverything(and you'll mock it if it doesn't).

author: Fungus
author_rank: Super Contributor
timestamp: August 20, 2016, 10:16:09 am
content: Quote from: JPortici on August 20, 2016, 10:05:23 amWhat are you monkeys yammering on about now?The original post (not written by me)wascomparing a 4-channel 'scope to an MSO.Here it is:Quote from: tautech on August 19, 2016, 10:44:52 pmIf the argument is that more expensive scopes (eg. 3x the price) have more features then you get a bigIf the argument is that nobody shouldeverconsider an oscilloscope that costs less than the oscilloscopeyoupersonally own then:a) I can point you to people who own more expensive oscilloscopes than youb) You still get a big

author: rf-loop
author_rank: Super Contributor
timestamp: August 20, 2016, 12:05:43 pm
content: Quote from: Fungus on August 20, 2016, 10:16:09 amWhat?It was you and no one else and exactly here where you compare these prices..Quote from: Fungus on August 20, 2016, 02:31:25 amNow I ask WHAT is 2.5 the price compaperd to DS1054Z.There was SDS1000X+Yes this Siglent MSO is more expensive than Rigol bottom model without MSO and FG.

author: nctnico
author_rank: Super Contributor
timestamp: August 20, 2016, 12:12:27 pm
content: Quote from: Fungus on August 20, 2016, 10:16:09 amPalm yourself. You are the one insisting everybody should buy a go-kart because it getsyoueverywhere you want to go with a comfort level + room for luggage you find satisfying. You totally fail to see that some people have more luggage, need more speed or just want more comfort and have the money to spend.If the argument is that nobody shouldeverconsider an oscilloscope that costs more than the oscilloscopeyoupersonally own then:a) I can point you to people who own less expensive oscilloscopes than youb) You still get a big

author: Fungus
author_rank: Super Contributor
timestamp: August 20, 2016, 12:22:41 pm
content: Quote from: rf-loop on August 20, 2016, 12:05:43 pmAnd thereforeshouldbe betterandhave more features....right?So you understand why I get confused when people come in here and say, "my 3x more expensive 'scope is better than that other one".("...and his 3x more expensive scope is better than yours, neener neener!")

author: rf-loop
author_rank: Super Contributor
timestamp: August 20, 2016, 01:27:38 pm
content: Quote from: Fungus on August 20, 2016, 12:22:41 pmYes, this is always confusing.And what is best for me in my use with my needs, my money, my taste and so on... this is very different question what is generally better, when generally best do not even exist and if we here loose totally what price class we are comparing we lost road totally.This was "best" oscilloscope for me some time ago... somewhere near end of -60's ? I can remember year exactly.But, this was absolutely best oscilloscope (for me) because it was only available with money I have at this time for scope.(also it was second hand but not old, like nearly new)This (same model, not this individual) was my absolutely best oscilloscope around perhaps near end of -60's. It meets my needs and it meets at this time also my available money for this.Still today, some times best (for me) is Tek 2246A and some times 2465 for my needs. (yes I use still also analog for some purposes with old equipments repaitr and when I want be fast. Turn on, connect probe, turn knob(s) and all is there, immediately, without thinking settings and worry if result is digital undefined bullshit - analog do not alias never.. no corners wobbling etc, all is just rock solid)And in some cases these old Tek's can not serve me at all.

author: vk6zgo
author_rank: Super Contributor
timestamp: August 20, 2016, 02:58:17 pm
content: Quote from: Wuerstchenhund on August 19, 2016, 11:23:20 amI have one of those------ I bought it a while back (maybe 8 years ago),so I could use it to fix my BWD 511.With 10 MHz bandwidth,the little Atten/Digitech has similar specs to the early 1970s BWD,but it has a tiny screen.The Telequipment S31 Serviscope was an early (late '50s ,early '60s ) "cheap" scope with proper triggering (but only 5MHz bandwidth).The price of an S31 in 1960 or so was,from memory,288 Australian Pounds ($A576) when my wage was around 6 Pounds ($A12) a week.Most people in that era,or even up to the 1980s were most likely to use an Oscilloscope at work,Uni,or Tech School.Personally owning a 'scope with the performance of a modern "Entry level" instrument would have been a distant dream for most of us.There were certainly Oscilloscopes with fairly impressive specs available,but unless you were a large organisation,or averyrich geek,you would never have been able to own one.QuoteIndeed,but they are better in so many ways than the things Tektronix & HP tried to foist on us in the dawn of the DSO era.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: August 20, 2016, 03:16:44 pm
content: Quote from: vk6zgo on August 20, 2016, 02:58:17 pmOf course, if only because as I already said the capabilities of a modern bottom-of-the-barrel scope would have been pretty much in the mid-range back then, a time when the 'bottom-of-the-barrel' equivalent would have been a simple, cheap Asian or East European single channel analog scope with 5Mhz or so BW, like the one in the picture.QuoteWhich could be equally said for modern mid-range and high-end scopes.QuoteYes, but again, this is due to normal technical progress and cost savings through high integration and cheap labor, not because the modern variant of a low-cost scope is inherently the better product (it is only 'better' because of the technical progress, after all HP & Tek had to work with the technology that was available back then). I'd even go as far as to say that inherently, these old Teks and HPs were the better products, because they offered better reliability and maturity as well as support. But then, hardly any of the early DSOs were classed (or priced) as entry-level scopes.

author: nfmax
author_rank: Super Contributor
timestamp: August 20, 2016, 03:18:59 pm
content: Quote from: David Hess on August 19, 2016, 09:54:35 pmSorry, not clear: I meant 4channels + external trigger > 4 channels > 2 channels + external trigger > 2 channels

author: nfmax
author_rank: Super Contributor
timestamp: August 20, 2016, 03:29:38 pm
content: It must have been about 1980, I met the late Viscount Downehttp://www.telegraph.co.uk/news/obituaries/1388827/Viscount-Downe.htmlthrough an optical fibre start-up company I was contracting to & he was investing in. As well as an Aston Martin enthusiast, he was an electronic 'hobbyist' who owned a Tektronix 7104, when this was The Best Oscilloscope In The World!There are hobbyists, and then there are hobbyists!

author: rf-loop
author_rank: Super Contributor
timestamp: August 20, 2016, 03:47:06 pm
content: Quote from: nfmax on August 20, 2016, 03:18:59 pmEven Siglent SDS2000X have 4 channel + Ext trigger (this Ext trig input is back side)But, here need also tell that Ext trig performance is not like main channels trig.In many new scopes trigger system is very different what previously.There is two main working principles. Analog side pathway trigger system where trig circuit take signal from analog front end just before ADC and then some kind of comparator system produce trigger.More modern way is full digital side trigger engine (like example in SDS2000X or SDS1000X and same in other brands) what give lot of more performance for many kind of complex triggering.This can do only with fully digitized channel. Time ago it was very difficult and mostly only in expensive scopes.In this kind of scope class if there is Ext trigger, it is afaik still "old school" analog trigger with limited accuracy and limited features. Also acquisitions fine positioning (interpolation between sample points and adjust to trigger point) is far below good full digital side triggering system (yes it can also be good but this kind of high quality complex circuits are not typical in cheap oscilloscopes)

author: nfmax
author_rank: Super Contributor
timestamp: August 20, 2016, 04:40:38 pm
content: Quote from: rf-loop on August 20, 2016, 03:47:06 pmHey, it wasn't me that said 4 channel scopes with external trigger inputs are very rare - I have two here on my bench!The utility of an external trigger input is it lets you measure the times of events on all four (or both) inputs, relative to some datum like a chip select or 1PPS signal, which is used as the trigger. You can of course correct for the unknown bandwidth & delay in the trigger by temporarily probing the trigger source using a signal channel while triggering off the external input. This tells you the trigger channel to signal input delay (and lets you confirm you are triggering on the right part of the signal). You then move the probe to the signal you want to look at, measure the delay with respect to the trigger point and add the trigger delay offset from the first measurement.

author: nfmax
author_rank: Super Contributor
timestamp: August 20, 2016, 05:48:18 pm
content: Quote from: rf-loop on August 20, 2016, 01:27:38 pmThe first oscilloscope I ever owned at home all to myself (around 1979) was a Solartron, rather like this one:http://www.thevalvepage.com/testeq/solatron/cd1183/cd1183.htm. However, mine used UHF connectors for the Y inputs, and I think it may have been 10MHz bandwidth. A chuck-out from the University. That plus an Avo 8, and home made PSU & function generator constituted my entire lab. Luxury!

author: pascal_sweden
author_rank: Super Contributor
timestamp: August 20, 2016, 05:58:44 pm
content: @rf-loop: You had details on the noise floor of the SDS1000X and SDS2000X series. There was a big difference between both series and the SDS1000X was better in some areas than the SDS2000X series, but then again there was an issue with the noise on the offset level.Where did you get these details? From Siglent or by your own measurements?Can you summarize these details once more with more details on how you obtained that information.I have only seen details on the noise floor for Rigol scopes, but never details about the noise on the offset level and wonder how Rigol compares there against Siglent.Maybe that information can also be obtained with hands-on measurements?It would be good to have the comparison in place between Rigol and Siglent

author: tautech
author_rank: Super Contributor
timestamp: August 20, 2016, 08:28:01 pm
content: Quote from: pascal_sweden on August 20, 2016, 05:58:44 pmThere are many examples of noise floor (and 0V trace offset) screenshots spread throughout the forum.From this post:https://www.eevblog.com/forum/testgear/siglent-sds2000-new-v2-firmware/msg807925/#msg807925Done with my old SDS2304 (not latest X series)Here's a GND input coupled screenshot.... Showing 0V offsetEditsFor clarity

author: nctnico
author_rank: Super Contributor
timestamp: August 20, 2016, 09:07:02 pm
content: Better use RMS, peak-peak measurement + statistics for determining the noise floor.

author: David Hess
author_rank: Super Contributor
timestamp: August 20, 2016, 09:17:25 pm
content: Quote from: pascal_sweden on August 20, 2016, 05:58:44 pmI read that discussion in detail and did not find any practical information on noise performance.The peak-to-peak and RMS measurement capability (and standard deviation - thanks nctnico) of these oscilloscopes should be able to directly measure their input noise accurately but for reasons unclear in that discussion thread, this was not reported. Relying on the index graded display is not the way to do it even on an analog oscilloscope unless tangential measurement is used which I am pretty sure cannot be done on a DSO because of limitations on how the display is rendered.The processing involved to produce a display from high record acquisition rates may alter noise measurements although if done correctly it should not.

author: David Hess
author_rank: Super Contributor
timestamp: August 20, 2016, 09:22:55 pm
content: Quote from: rf-loop on August 20, 2016, 03:47:06 pmThe old school analog triggers are usually limited by noise in the source rather than internal jitter and digital triggers have the same limitation. The digital triggers produce nice displays showing zero trigger jitter (LeCroy used to make a big deal about this in their advertising) but it is an illusion; the jitter shows up before and after the trigger point. Even when not limited by noise in the source, analog triggers still product less jitter than can be observed unless you are using a real sampling oscilloscope where you get down into the 10s of picoseconds.The reason digital triggers displaced analog triggers is simply because once you have enough digital integration, they are cheaper and of course you also get the benefits of complex triggers but again, that is because of increasing digital integration. Moore's Law does not apply to analog triggers.Does the external trigger on the Siglent SDS2000X use interpolation or is its timing resolution limited by the sampling clock? I would worry about the same problem when using MSO inputs for triggering; the SDS2000X datasheet says 500 MSamples/sec for the digital inputs implying 2 nanoseconds of jitter if they are used for triggering. For the external trigger input if it is tied to the sampling clock, then I would assume 1 nanosecond of jitter.Note: It took me 15 minutes to get this reply posted after writing it. I hate this forum software.

author: David Hess
author_rank: Super Contributor
timestamp: August 20, 2016, 09:32:56 pm
content: As long as we are posting photographs which reveal nothing about noise performance, here are a couple which illustrate a potential problem.The 2440 and 2232 were used to observe the same set of signals from the startup of a Tektronix 7000 series switching power supply. Both oscilloscopes are using peak detection which raises apparent noise. The 2232 photograph (the horizontal position is deliberately shifted so as not to obscure the cursor readout) shows much less noise especially on the lower trace. Guess what is going on here.

author: nctnico
author_rank: Super Contributor
timestamp: August 20, 2016, 09:43:01 pm
content: I guess the2440samples at a much lower frequency but modern DSOs use the maximum samplerate which is at least a couple of times the bandwidth to do peak detect.edit: make that the 2232 which samples slower.

author: Jwalling
author_rank: Unknown
timestamp: August 20, 2016, 09:58:41 pm
content: Any chance it could be crosstalk between channels? (WAG)

author: julian1
author_rank: Frequent Contributor
timestamp: August 20, 2016, 10:15:17 pm
content: As a beginner, I'm very happy with my Rigol 1054Z.But I'm even happier I arranged my budget to purchase a sig-gen with it.The combination allows me to think about and prototype circuits as devices consisting of inputs and outputs. The siggen is used to create the test input, while the oscilloscope provides visibility on the output.

author: David Hess
author_rank: Super Contributor
timestamp: August 20, 2016, 10:18:13 pm
content: Quote from: nctnico on August 20, 2016, 09:43:01 pmI would consider these "modern" DSOs since they do the same thing; the maximum sample rate is used for peak detection. The 2440 is sampling at 500 MSamples/second (per channel) and the 2232 is sampling at 50 MSamples/second (per channel) because both are in peak detect acquisition mode. That zig-zag looking aspect of the 2232 display where the 2440 display is filled in has to do with limitations of the display controller in the 2232 and nothing to do with the signals.No aliasing is present in either photograph and there is no crosstalk; it is very difficult to generate aliasing on these oscilloscopes when peak detection is used. The critical part to look at is the upper trace before the 3rd horizontal division and the entire lower trace on the 2232. Compare both to 1st horizontal division of the traces shown by the 2440 which is before the power supply is even turned on. How can the 2232 traces be essentially noise free especially when peak detection is used? They cannot be; something else is going on.Update: Nothing is going on which has to do with sample rate. No external noise sources were present; connections were coaxial to minimize noise pickup both from external sources and the power supply itself. For all practical purposes, input noise was zero before the power supply was turned on.

author: vk6zgo
author_rank: Super Contributor
timestamp: August 21, 2016, 04:53:53 am
content: Quote from: Wuerstchenhund on August 20, 2016, 03:16:44 pmWhen most Oscilloscopes were purchased by organisations rather than individuals,the "Entry level" would have been that for small Radio/TV service shops,where something similar in performance to the BWD, or the Telequipment S31would have been (just) adequate.The next level up would be that of Unis & Tech Schools.Up from that would have been large Communications & Broadcasting organisations,which went from Tek 545s & the like,up through Tek 7000 series,to the last generation of Tek & HP Analogs. (mid level?)In many cases,it wasn't the wider bandwidth which was important,so much as better triggering,Delayed timebases & so on.In the late 1980s/early'90s,most people in this type of work were quite familiar with digital based equipment (for the youngsters reading--yes,there was digital equipment before microprocessors).Perhaps for that reason,we expected more from the early DSOs we were offered,without considering that the design of such instruments was a lot more difficult than,say that of a digital video device which only had to operate 0-5MHz.Alas,we were disappointed---the early DSOs were incapable of performing standard video tests,due to the large reduction in sample rate at PAL field rate frequency.They were,for our purposes,useless pretty boxes,so we had no way to measure their reliability or support.Modern DSOs could,in the main perform such tests,which although analog TV is gone,have their equivalents in other fields.

author: rf-loop
author_rank: Super Contributor
timestamp: August 21, 2016, 10:16:39 am
content: Quote from: David Hess on August 20, 2016, 09:22:55 pmDo we now talk anything about same things.Please read what is conventional (aka analog) trigger circuit principle in digital oscilloscopes and what is modern digital trigger.It can read example here.(R&S RTO Oscilloscope's Digital Trigger)Reason is not to be cheap. Reason is Improve performance over old ancient conventional and cheap analog trigger in digital oscilloscopes. This was time ago possible only in expensive oscilloscopes. Today (as you told we get more integration and lower cost for functions) we can have this also in lower end of oscilloscopes.Still due to much more easy old simple conventional analog trigger (in this R&S paper chapter 1. Conventional trigger) is used in bottom level digital scopes. Good examples are Rigol DS1052E and example Siglent SDS1102CML etc.Siglent SDS1000X/X+ SDS2000X use this principle what is in this R&S paper, Chapter 2: Digital TriggerFirst advantage in digital trigger is that there is one signal pathway from input to ADC and acquisition data for display is exactly same what trigger get. No different delay and frequency bandwidth. In conventional (analog) system there is two signal pathway after analog front end amplifier. One to ADC for sampling and one to trigger circuits. Trigger circuit may see very different signal what is signal after ADC. More explained in this paper.About digital channels and triggering. What can interpolate if have only and exactly two states 0 and 1.There is not method to do oversampling and interpolate if there is not more information than sample clock and comparator result 0 or 1. Not even in theory until there is some more information available. In digitized analog channel there is.Sidenote: Also nearly end of this paper, R&S explain also one more thing what Siglent have in these X series models. (3.7 History View Function)

author: pascal_sweden
author_rank: Super Contributor
timestamp: August 21, 2016, 11:21:38 am
content: @rf-loop: Can you revisit this topic?Quote from: David Hess on August 20, 2016, 09:17:25 pm

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: August 21, 2016, 11:55:10 am
content: Quote from: vk6zgo on August 21, 2016, 04:53:53 amBack then many of the scopes used by TV repair shops (in Germany usually some Hameg) could be found with many serious hobbyists as well.Then there was a crop of even cheaper scopes coming from Eastern Europe (i.e. GDR, USSR) which were resold by Western electronics vendors under their own name for (back then) relatively low prices.QuoteUnderstandable considering your field (TV/video). Back then for us they opened up doors that no analog scope could, simply because we finally had proper means to digitize waveforms at increasingly higher sample rates for further processing. And the '80s did had some really decent DSOs for us, i.e. the Philips PM3320.

author: rf-loop
author_rank: Super Contributor
timestamp: August 21, 2016, 12:26:43 pm
content: Quote from: pascal_sweden on August 21, 2016, 11:21:38 amI can not see any dedicated reason for this.SDS1000X and SDS2000X works normally as designed and manufactured and related to noise I can not see any issue what need talk about. Both they are quite good in this class of scopes if we talk about noise. Also I do not understand what you mean that SDS1000X and SDS2000X have "big differencies" and then that in some things SDS1000X is better in some areas. What?Only "better" in SDS1000X is that it have real 1mV and 500uV/div sensitivity when SDS2000X have 2mV/div sensitivity (+1mV/div derived digitally from 2mV/div - just as also some Agilent do)I can not see any problem issues there. Not in noise and not in offset setting. They works just normally as designed without issues in noise and vertical offset etc.Totally other question is if we start talking about what is nice to have and how things can develop better. You know that also good can develop better, also exellent can develop better, just as also crap can develop better. Even state of art level things can develop better.If want develop example SDS1000X analog front end better it can of course do. And Then we can talk about what are things what need firs develop better if start developing it. 1/f noise can reduce (what ever is source of this) and Offset setting resolution and accuracy can develop better. Specially when we talk about 0.5mV/div but also 1 and 2mV/div. After these next can develop lower wide band noise. Also 50ohm impedance can develop better so that it is more accurately 50 ohm impedance over whole frequency bandwidth and bit over. Then next frequency response can develop better, so that it is as flat as possible over whole BW but then soon after nominal freq like "brick wall" sharply down.And so on and so on.And please do not now convert these all what I say that these are some issues/problems in these scopes!

author: tautech
author_rank: Super Contributor
timestamp: August 21, 2016, 12:47:22 pm
content: Quote from: rf-loop on August 21, 2016, 12:26:43 pmI started compiling some screenshots today to show this, I won't be posting them in this thread only the SDS1kX thread and just one unit (SDS1kX+) I tested showed zero trace offset after an Autocal but was out somewhat before the Autocal.I'll pull at least 1 more new SDS1kX unit out for the same tests, doing my pre-sales checks at the same time.A SDS2304X will get the same treatment and those screenshots will will get posted in yet another thread.So Pascal will get his much desired screenshots, he'll find them easy as they'll be in threads that he's already posted in. Got a bit on so they'll take 24-48 hrs.

author: nctnico
author_rank: Super Contributor
timestamp: August 21, 2016, 02:04:04 pm
content: Better post them here for comparison. There is no use otherwise because the other threads will become littered with comparisons and making a non-comprehensible mess.

author: tautech
author_rank: Super Contributor
timestamp: August 21, 2016, 08:20:25 pm
content: Quote from: nctnico on August 21, 2016, 02:04:04 pmI won't. Period.If anything they'll be OT and more worthy of a separate thread titled DSO Baseline noise and Offset.Threads like this turn into pissing competitions, any images I post will be statements of fact and best left in dedicated threads.If any reader can't then open another tab on their browser and compare competing brand screenshots side by side what hope have they got attempting to use a scope?Members need always consider how they word or title any post they make so content can easily be found with forum searches.

author: nctnico
author_rank: Super Contributor
timestamp: August 21, 2016, 08:45:32 pm
content: Creating a different topic with noise & offset crossed my mind as well and would be benificial as a reference. But perhaps it is an option to use the pictures posted in various other threads to compose a comparison in a new topic.I'm not quite sure the offset is interesting though. Normally a self- calibration after a warm up period should set this to zero and unless the scope is used at a much different temperature I expect the offset to remain zero for a while (a couple of months to a year).

author: David Hess
author_rank: Super Contributor
timestamp: August 21, 2016, 09:05:29 pm
content: On the 2232 what is going on is that in peak detect mode, processing is used to remove residual noise apparently in a way similar to how a noise gate works. The reason this is relevant to modern DSOs is that many include the same type of thing making self measured noise comparisons difficult even without the issued involved in interpreting the display.Tektronix documented this feature on the 2232 but it was easy to miss in the manual unless you were already aware of it. It can be easily disabled in the user interface with two button presses, which is how I first became aware that it was in the manual somewhere, in which case it produces results which accurately match the 2440 and most other DSOs, or at least the ones which do not process the hell out of the data. I first noticed it later after the photographs were taken; had I noticed immediately, I would have taken a third set for comparison purposes. It is not a bad feature, works incredibly well, and is occasionally useful especially for documentation purposes, but I am glad Tektronix included the ability to disable it because it can be misleading.So if you want to measure DSO noise, use the built in peak-to-peak, RMS, and standard deviation measurement capability; if they do not work on noise, then they are broken. Then make sure they return consistent results with different operating modes, number of channels, and vertical and horizontal settings. If you are ambitious, check them against an external noise standard. If you have to, break out a dual channel analog oscilloscope (look up tangential noise measurement) or RMS sampling voltmeter to make a good RMS noise measurement of your noise standard for comparison purposes.Also see if the input coupling mode affects noise with and without an external short since so many DSOs now misleadingly do not have actual ground coupling even though it is listed in the coupling menu. I suspect this "feature" in DSOs is deliberate or if for economic reasons, then deliberately not documented, to make their noise performance look better.

author: nctnico
author_rank: Super Contributor
timestamp: August 21, 2016, 09:25:07 pm
content: It is the first time I have heard about a noise gate in a DSO. If the 2232 is using a CCD for sampling it would make some sort of sense though because CCDs are very noisy. I doubt they use noise gates on modern DSOs which use a fast ADC. The amount of processing required would be substantial.

author: David Hess
author_rank: Super Contributor
timestamp: August 21, 2016, 10:38:17 pm
content: Quote from: rf-loop on August 21, 2016, 10:16:39 amI have read that paper before and it is easy to take out of context. At 500 MHz and below, jitter from a properly operating analog trigger is insignificant.The performance considerations discussed in that paper apply to a 4 GHz 10 GSample/second DSO. A typical analog trigger even 30+ years ago supported 2 to 20 GSamples/second equivalent time sampling which requires trigger jitter in the 500 to 50 picosecond range and it is not difficult to achieve a jitter of 10 picoseconds. This level of jitter is not significant at the bandwidths these triggers are designed to support.QuoteThe advantage of digital triggers include:1. With increasing integration, they are cheaper than analog triggering.2. They can operate in real time whereas analog triggers have relatively long holdoff times.3. They support exotic trigger modes.But for cheap oscilloscopes, the overriding reason is that with increasing integration, digital triggers are effectively free while analog triggers require dedicated hardware. If analog triggers were cheaper, than the cheapest (real) DSOs would be using them.QuoteI have never even seen this come up as a problem although based on reports I have heard, it might have been an issue with certain manufacturers like HP. You might be surprised at how dissimilar the vertical and trigger signal paths can be before it affects anything.It gets weird when you consider analog trigger designs which have *much* higher or lower bandwidth than the vertical signal path which is common with sampling oscilloscopes but some analog oscilloscopes have this as well. The only time I have seen it make a difference is when the trigger source has an unusually high but narrow bandwidth which a low bandwidth trigger cannot even see. A couple of times, I have used a 500 MHz 7B92A timebase in my 100 MHz 7603 mainframe just so I could externally trigger on a narrow digital strobe which the normal 100 MHz trigger could not reliably act on.QuoteMost 2-channel DSOs apparently digitize their external trigger input avoiding this problem and I would consider them completely broken if they did not. So the only difference between their vertical inputs and external trigger input may be lack of signal conditioning and acquisition memory storage for the external trigger input. This implies that the difference between a modern 2-channel DSO with external trigger input and a 4-channel DSO is less than the manufacturers charge for.In the past there were logic analyzers which digitized their digital inputs so could in theory implement precise trigger timing. The Tektronix TLS216 "Logic Scope" at 2 GSamples/second has a specified timing resolution of +/- 100ps so I assume it did this. Apparently logic analyzers like this are invaluable in some applications.http://www.tek.com/datasheet/tls216https://www.eevblog.com/forum/testgear/tektronix-tls-216-16-ch-logic-scope-any-experiances-with-that-tool/

author: nctnico
author_rank: Super Contributor
timestamp: August 21, 2016, 10:56:45 pm
content: Quote from: David Hess on August 21, 2016, 10:38:17 pmAFAIK most current high end logic analysers from Tektronix and HPAK work this way. The one from Tektronix I have samples the inputs at 8GHz which is then processed into sampled data. This allows to define precise setup and hold timing for a synchronous clock.Still in a DSO you'll need to do some trigger interpolation to overlay subsequent acquisitions precisely otherwise the trace will jitter on the screen. 800x480 is a commonly used screen resolution. When using 600 horizontal pixels for the graticule at 10ns/div and 1Gs/s each pixel will account for 10ns/600/10 divisions=166ps. A 1ns jitter in the trigger will move the signal 6 pixels from left to right. You'll see that for sure.

author: David Hess
author_rank: Super Contributor
timestamp: August 22, 2016, 12:46:01 pm
content: Quote from: nctnico on August 21, 2016, 10:56:45 pmThat is something I have wondered about on DSOs which use a digital trigger but never had an opportunity to test. What happens with a bandwidth limited edge? Aliasing should move the trigger point around.