Open-source digital oscilloscope "ScopeFun" - Page 1
Forum section: electronics / general

author: Free_WiFi
author_rank: Regular Contributor
timestamp: April 06, 2019, 01:34:34 am
content: ScopeFun - Open Source InstrumentationSeveral instruments in one deviceOscilloscope, Arbitrary Waveform Generator, Spectrum Analyzer, Logic Analyzer, Digital Pattern Generator.Open sourceSoftware, firmware and hardware sources are available for free. All under open source license.Cross PlatformSoftware runs on Windows, Linux and Mac.SpecificationsOscilloscopeNo. of Channels: 2Analog bandwidth (-3 dB): 100 MhzSampling rate, max.: 250 MSps dual ch. (500 MSps single ch.) / 2,0 Gsps with Equivalent-Time Sampling (ETS)Sampling rate, min.: 50 SpsResolution: 10 bitMemory depth: 128.000.000 samples per channelVoltage ranges (with 1× probe): 10 mV, 20 mV, 50 mV, 100 mV, 200 mV, 500 mV, 1 V, 2 V per divisionVoltage ranges (with 10× probe): 100 mV, 200 mV, 500 mV, 1 V, 2 V, 5 V, 10 V, 20 V per divisionInput Offset: adjustableInput coupling: DC, AC, GNDInput impedance: 1 MΩ || 18 pFMax. input voltage: +/-20 VOvervoltage protection: +/- 50 V ( permanent )LED trigger indicatorWaveform GeneratorNo. of Channels: 2Sampling rate: 200 MspsResolution: 12 bitOutput impedance: 50 ΩOutput amplifier bandwidth: 30 MhzWaveform shapes: Sin, Cos, Triangle, Saw, Ramp up/down, Delta, DC, Noise, CustomCustom waveform memory: 32.768 Samples per ChannelMax out. Voltage: +/- 2,0 VOffset and Level adjustableOvervoltage protection: +/- 25 V ( permanent )Short-circuit protectionLogic Analyzer / Pattern GeneratorNo. of Channels: 12 (logic analyzer / pattern generator: 6-input / 6-output; 12-input; 12-output)Sampling rate: max. 250 MspsInterface voltage: Adjustable 1,25 V - 3,3 V in 256 stepsLA Memory depth: 128.000.000 samples per channelInput Impedace (Logic Analyzer): 200 kΩOutput Impedance (Pattern Generator): 1 kΩOvervoltage protection: +/-5 V (Permanent); +/- 12V (Short term ~ 10 s)Pattern Generator memory: 32.768 Samples per ChannelPattern Generator internal clock divider: Adjustable 32-bit (250 Mhz - 0,058 Hz)TriggerSource: Analog Ch. 1, Analog Ch. 2, Digital Ch. (external), Generator Ch. 1, Generator Ch. 2Mode: Auto, Normal, Single (with Re-Arm)Pre-Trigger: Adjustable 0 - 99%Trigger Level: 0 - 100 %Trigger Level Hysteresis: AdjustableTrigger Holdoff: Adjustable 0 - 17 s (4 ns step size)Digital trigger: 4 stages (with delay counter for each stage)Digital trigger: selective channel masking (logic levels: '0', '1', 'Rising', 'Falling')The price for the full kit is rated more then : $700Related linkshttps://www.scopefun.comhttps://www.scopefun.com/https://www.scopefun.com/gallery/ScopeFun_v1/1-16-67https://www.youtube.com/channel/UCd2G5c2wmahLIKfNnVobr7Qhttps://medium.com/@ScopeFun/scopefun-oscilloscope-development-update-1-b64f8a2fd085Arrived at this point,i wish to ask the people of EEVBlog if this scope did really worth the effort to be made in home conditions.I haven't too much cash in my own pocket for an "high end-mid range scope" but this project looks to be very delicious and so on.....However tell me please what do you think about,thanks to all.

author: NiHaoMike
author_rank: Super Contributor
timestamp: April 06, 2019, 04:52:05 am
content: I wonder if, by changing the firmware and adding some RF front end circuits, it could double as a SDR platform?

author: capt bullshot
author_rank: Super Contributor
timestamp: April 06, 2019, 08:37:15 am
content: Quote from: Free_WiFi on April 06, 2019, 05:11:51 amNo, IMO this statement doesn't mean your DSO is bullshit. Indeed, it looks quite nice, way better than many other USB scopes.To double as an SDR platform means, NiHaoMike thinks this hardware is powerful enough to sustain high data transfer rates, is able to do pre- and postprocessing (like up- and down- mixing) within the FPGA, or maybe the complete signal processing for SDR can be done within the FPGA. So basically by adding some RF inputs and pre-amps, your DSO could be also used as a powerful platform for SDR development.

author: Free_WiFi
author_rank: Regular Contributor
timestamp: April 07, 2019, 03:41:34 am
content: So basically,someone of you would be ready to reapeat it by posting the final result on this thread ?It would be very,very nice

author: james_s
author_rank: Super Contributor
timestamp: April 07, 2019, 04:31:01 am
content: $700 for 2 channels, 100MHz bandwidth, 500MS/s when only using 1 channel? Logic analyzer is only 12 channels, that's not even enough to debug an 8 bit microprocessor system, I must be missing something because this doesn't sound like any bargain to me. Doesn't sound any better than the low cost Chinese DSOs and those are standalone not tying up a PC. For $700 you could get standalone instruments that exceed the specs of this thing.

author: AndreZheng
author_rank: Contributor
timestamp: April 09, 2019, 01:35:11 am
content: I do also really love this amazing project. But the target price $700 is really too high for me. You may know $700 can almost buy a really low end oscilloscope, e.g. Keysight(Agilent) DSOX1000 series.If I were this project's designer, I will make the product's cost down to around $200. And I'll do following modifications to make it happen.(1) Replace the 10bit@250Msps ADC with 8bit@250Msps ADC.(2) Separate the single board into two boards. One board for USB3.0 chip CYUSB3014 + FPGA + DDR3 + Expansion IOs; The other boards are standalone boards like Pure IO board, or ADC board or DAC board, etc. In this case, different boards can meet different people's need.

author: james_s
author_rank: Super Contributor
timestamp: April 10, 2019, 05:40:57 pm
content: Yeah I think at $200 it might be a fair deal for people who are on a tight budget, but personally I'd still rather have a standalone ~$350 Rigol or Siglent DSO. Standalone scopes with real buttons and knobs are so much more convenient than PC based instruments. I think PC based never really delivered on its promises, the cost of the display and processing dropped to the point that the savings of utilizing a shared PC is minimal vs having a dedicated computer and display built into the instrument.

author: NiHaoMike
author_rank: Super Contributor
timestamp: April 11, 2019, 03:59:22 am
content: In my experience, even rather expensive DSOs like the MDO 4000 I have used in an automated test system for work leave much to be desired in many ways. One I have yet to see done right is high speed streaming of data to a PC. I could quickly download screenshots at 1024x768, barely enough for 3 nonoverlapping analog channels at 8 bit, let alone 10 bit channels and/or digital channels, not to mention the annotation that also takes up space. (And if you want a white background, doing it in the scope itself leaves ugly dark fringes around each trace - I ended up implementing a bit of Python code to take the image with a black background, invert it, and remap the colors.) Or I could download the capture data at way too slow a rate to be useful for high speed testing.And when it comes to bus debugging, the MDO is so slow that I would classify it as barely better than nothing. A $6 FX2 board along with Sigrok gives a much better user experience. (I would like to see the FX3 get official Sigrok support - that would make it the ultimate budget logic analyzer for most hobbyists and even many small companies. I used to work at a company that used Beaglebone Black boards for I2C and SPI analysis because those were cheap enough to provide several for every developer, plus the Ethernet port made it trivial to install in a remote test rack.)If I were to suggest a path, start by getting a FX3 based logic analyzer supported under Sigrok. Then add a FPGA to allow capture of even faster signals and interfacing to ADCs. I wouldn't invest much effort into streaming to a high speed DAC when the $5 fl2k will do 3 channels at 8 bit/150MSPS.

author: tkamiya
author_rank: Super Contributor
timestamp: May 16, 2019, 11:23:03 pm
content: If the board alone is $700, completed project, case, power supply, and everything else will probably run more than $1000. Then, I assume those functions that this board can do will be one at a time. Can you have scope running and function generator running at the same time?If I look at scope spec alone, you could do a lot better by going with used Tektronix. Mine happens to be refurbished by Tek itself and was $300. My preference is to go with older but well characterized individual test equipment. For $1000, you can buy a lot if you know where to look.

author: prasimix
author_rank: Unknown
timestamp: May 17, 2019, 06:25:26 am
content: If everything is reduced to the cost then ScopeFun is not a winner for sure. But, if we put into picture open source design that is not just promised but alreadydelivered, and put into perspective that project team probably will continue to improve software/firmware part of the ScopeFun than it is something completely different. That include real possibility that you and I could ask or influence project team to modify or add new features in software/firmware. A rare luxury in case of commercial brands.Open source doesn't mean a lot until device failed. I had such situation with Rigol a year ago: bought as brand new that last a little bit over two years and then mysteriously failed. Service cost with shipment was comparable to new unit (500+ EUR) and I decided to buy a new unit. The whole story could probably end differently that Rigol was an open source.The main obstacle for me to get one ScopeFun is its format: it's unfortunately a PC scope. I found that quite inconvenient in practice (I also havePicoscope 4444): I cannot put PC on my desk top where is DUT, not to mention that most of control is reachable only by mouse that require more time to set desired values then using front panel knobs. With special arrangement of the desk top I probably could make its usage more efficient without constantly moving my head left and right as on the tennis court. Yes, a speech recognition would improve usability a lot when comes to control, but require some integration work since Picoscope doesn't offer such thing out of box.

author: OwO
author_rank: Super Contributor
timestamp: May 17, 2019, 07:42:44 am
content: Open source by itself is not a good enough selling point, your product has got to be competitive on its own without considering that it's open source. I do have a open source hardware startup and my main competitive advantage is still bang for buck, not just that it's open source.

author: prasimix
author_rank: Unknown
timestamp: May 17, 2019, 09:02:33 am
content: Thanks for reminder. Luckily for the open source community your worldview even as continue to be a prevalent is not the one and only.My compliments to David and Dejan for doing a great job. This project is a great contribution to people who is willing to learn something about T&M solutions and push boundaries of DIY/makers solutions to the next level. I do believe that forthcoming crowdfunding campaign will be successful. For other, possibly some company from your neighborhood will start to clone it massively and push the price down. We'll see, that could be a great sign that Scopefun is recognized and attractive and can give Scopefun team a good reason to move it forward.

author: 2N3055
author_rank: Super Contributor
timestamp: May 17, 2019, 10:45:08 am
content: Quote from: prasimix on May 17, 2019, 09:02:33 amYeah guys that designed this made a nice proof of concept that shows their knowledge. Compliments.If I were hiring, all they need to do is to show this project and they would get the job.Is it pushing boundaries of DIY T&M solutions ? Nah, not really.Specifications are pedestrian and price is so high you can equip whole lab with pro made equipment for the price. For an average hobby lab repairs are going to be hard, most people cannot replace BGA on board without destroying it all... No tools for that.It's not a worldview, it is reality. Recommending people to buy half cooked project prototypes for huge amounts of money because it is for a good cause ("Open something") is at best misguided, at worst misleading. And that is just because I genuinely believe you have good intentions. Otherwise it would be simply dishonest and fraudulent.Open source means something only if a poor kid from a third world country can afford something that would be impossible at the prices that are being charged by likes of Keysight and Tektronix etc...Sorry to burst your bubble, but low cost Chinese T&M equipment does that job much better than any Open source project now in existence.Is this a project that designer should be proud of? Yes definitelyWould I recommend it to anybody? No, not really, for the money.For maybe 150-200 USD, yes definitely, but with a disclaimer it is a developer kit, not finished, ready to use instrument. Cause it is not, and it is not given it will ever be. That still remains to be seen.

author: james_s
author_rank: Super Contributor
timestamp: May 18, 2019, 12:44:08 am
content: I agree, I'm a big fan of open source, but unless I had money to burn and wanted to make a statement by investing in a project like this I would look elsewhere. Open source makes sense when it allows cheap commodity or self built hardware to to the job of much more expensive closed source gear, or when it can do something truly unique or the fact that it can be customized to the extreme makes it more versatile. In cases like this though it seems like it does less than the competition while costing a whole lot more. I've seen too many open source projects get halfway there and then be abandoned by the creator when they get bored and move onto the next shiny thing without a support & development community really taking off.Open source is good, but in the end it comes down to price. In many cases I'm willing to accept something that is not quite finished in exchange for a substantial savings of money but when I can buy a polished commercial product for less then there's no reason not to. If it does everything I need it to do I don't care if it's open source.

author: NorthGuy
author_rank: Super Contributor
timestamp: May 18, 2019, 04:54:29 pm
content: I don't know why you would expect open source to be cheap.A well funded manufacturer may produce things in millions, and cost per piece will be a fraction of the production of a single item. The price of the item on the market is determined by supply and demand. Most of what you pay for commercial things is to cover sales and management. Production is a smaller portion, R&D is even less. The company's profit may be a tiny fraction of the cost, may even be negative.With open source you get free R&D, no sales, no management, no profit to anyone. All you need to pay for is production (but in small quantities).How's that even possible to compare the two?

author: james_s
author_rank: Super Contributor
timestamp: May 18, 2019, 07:13:57 pm
content: Quote from: NorthGuy on May 18, 2019, 04:54:29 pmUmm, because it almost always is?Linux is free, KiCad is free, Inkscape is free, GIMP is free, virtually all open source software is free. It may not always be quite as good as the high dollar heavy duty commercial stuff but because it's free it gets widespread use and improves. The Arduino and countless clones are dirt cheap, the market is flooded with crazy cheap open source products and derivatives of these products, because they're open source you can build your own copy of them as I have done in numerous cases. ARM boards, FPGA boards, modules and widgets, all sorts of low volume hobbyist projects and kits, it's virtually all either much cheaper than a commercial solution or it does something that is not available in a commercial solution at any price.Why would I NOT expect open source to be cheap? If I can't save money then why on earth would I go with a half baked open source project vs a polished, completed, supported commercial product?

author: 2N3055
author_rank: Super Contributor
timestamp: May 18, 2019, 08:56:44 pm
content: Quote from: NorthGuy on May 18, 2019, 04:54:29 pmOpen source anything should either be very inexpensive or free.Otherwise there is no reason for it it to exist.Otherwise it just that some first world hipster wants me to pay him to have a hobby, that nobody will benefit from except him...And companies that are manufacturing stuff at prices nobody else is stupid enough to pay for.Simple as that.That is why Open Source software is possible and can be beneficial to humanity. Many nice people are using their free time to make software that is free to legally install and use to accomplish something they wouldn't be able to afford otherwise. All this human time (engineer hours) is donated by kind people, or even companies (when it helps them or makes them look good or also sometimes purely as goodwill). End users get a usable product (sometimes as good as paid one, or if not as good, good enough for many purposes, aka better than nothing.) and it all works because price of manufacturing copies (replication and distribution) in software is very low. So R&D donated, manufacturing almost free. And it works because it is hell of a deal for the money.Software people don't like it when someone say it, but software is easy.. No, wait, not fair. It is very hard to make and make right and it not easy. But it is more straightforward to test and easier to fix.You just apply patch and problem is gone. If after a year, developers realize architecture is wrong, the can (and they do) make a new major release. You download and upgrade. Life goes on.And that is why Open something in hardware doesn't work. Hardware mistakes cannot be patched from online update. PCB's need to be respined. Components on bad one cannot be reused.And once it is made to work nicely, you cannot add 2 more channels just like that. Pretty much you have to start from beginning. Than EMC. Even if you don't care if you radiate like crazy, you have to make it resilient to outside EMC. Otherwise it will be unreliable and won't work properly... Measurement instrument will inject crap into signal you're measuring, all kinds of spurs... That won't be properly characterized and documented so you can expect them in results you you know it's not DUT.....On Open something hardware, only firmware is open, and that has it's limitations, because embedded processors have limited resources... So you can fix some problems, even redesign few little things but major new release means new PCB and parts for 1000 USD. Old one is electronic waste.All of the Open Something hardware that exist and is somewhat useful has fixed hardware that is much cheaper than commercial counterparts, and only Open part is software (firmware and PC part).And many time hardware is cheaper because it has hobby grade specifications, that are great for hobby and education. Great example are many SDR modules out there.And they are great, because there are tens of thousands people in the world that are given opportunity to learn about SDR on something they can afford.Like James said, if it is not much cheaper that real thing,it shouldn't exist. Otherwise we are all simply financing some hipster to have a hobby. No, thanks.

author: NorthGuy
author_rank: Super Contributor
timestamp: May 19, 2019, 02:02:59 pm
content: Quote from: james_s on May 18, 2019, 07:13:57 pmBecause you can tweak it. You can get the files, change them as you like, build your own. That's the only difference between open and closed. If someone sells you an assembled scope board for end use, then you're only interested in its characteristics and the price. Why would you care if it's open or not? Would you tell the seller that he must drop his price because the hardware files are open?If you buy an Arduino board - it's a commercial product. Someone invested money to buy parts, build boards in huge quantity, and now he's selling them to public in small quantities for profit. He could have taken an unmodified open hardware project, or he could have modified it, or he could design entirely his own. Either way, the design expense is a fraction of the overall cost, and there's no difference to the end user.

author: james_s
author_rank: Super Contributor
timestamp: May 19, 2019, 05:36:34 pm
content: Who wants to tweak their oscilloscope? Being able to modify it is a nice bonus, but I cannot think of a single successful open source product that costs more than a comparable commercial product. Open source succeeds primarily because it is cheaper than another option, and the ability to modify it yourself partially makes up for the fact that it is nearly always not quite as polished as a commercial off the shelf solution. The open source device you can tweak to reduce the deficiencies (if you are the small percentage who have the necessary skills) vs the commercial product you pay more but you get a finished, tested, supported product that does not have those deficiencies.Can you think of even one open source project that is popular despite costing more than closed source products that do the same thing? I can't, but if there is one I'd be curious to know about it.

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 19, 2019, 06:47:53 pm
content: Quote from: james_s on May 19, 2019, 05:36:34 pmPrusa 3D printers have been and still are popular despite there being lots of cheaper printers available.

author: james_s
author_rank: Super Contributor
timestamp: May 19, 2019, 07:01:03 pm
content: Is there a comparably priced commercial off the shelf 3D printer that works as well or better? I haven't been following hobby grade 3D printing recently but what makes the Prusa printer popular? Is it the fact that it's open source, or does it do something that a commercial solution can't do or do as well?From what I have seen, 3D printers are generally speaking another example of a low cost hobby product, they don't work as well as megabuck proprietary industrial 3D printers but their open source nature has enabled them to evolve into a product that is good enough while being affordable and accessible. Once again their success comes down to the fact that they are (relatively) cheap.

author: Mechatrommer
author_rank: Super Contributor
timestamp: May 19, 2019, 07:43:42 pm
content: Quote from: NiHaoMike on May 19, 2019, 06:47:53 pmi guess people who bought original Prusa were comparing it with much more expensive unit, but dont want the hassle to tweak/modify nor risk of non working printer, they want some assurance/guarantee/warranty from the seller, this is a portion in the market segment. but for some people with "some" knowledge or willingness to tweak they will buy much cheaper knock off prusa/china/open source unit. and from my limited historical background reading, Prusa maker is among the early mover on this OSHW product (based on Adrian BowyerRepRap project) which is cheaper than the now bought MakerBot etc where no other knock off brands in competition, so he gathered some "resources" already, so he can continue on.

author: NorthGuy
author_rank: Super Contributor
timestamp: May 19, 2019, 08:07:18 pm
content: Quote from: james_s on May 19, 2019, 05:36:34 pmI don't understand the juxtaposition. Lots of commercial off the shelf solutions use open source hardware.Quote from: james_s on May 19, 2019, 05:36:34 pmLooks at the "Test Equipment" forum section. Commercial solutions are anything but polished. There are software bugs, firmware bugs, hardware problems, reliability problems, usability concerns, limitations etc. etc.Quote from: james_s on May 19, 2019, 05:36:34 pm"Popular" products are mass produced and thus cost less. This has nothing to do with the open source-ness. Say, Arduino is popular and cheap. If you decide to produce and sell Arduino in small quantities, your product will be terribly expensive, or you will go bankrupt.

author: nAyPDJ
author_rank: Contributor
timestamp: June 16, 2019, 03:19:49 pm
content: I've built the v1 of this scope, which has 16 digital channels but just 100MSa/s. I bought the parts for 2, and split the cost with a friend, so it came out to $239.38/ea.It took me about 7 hours to solder & assemble the scope. I was inexperienced with soldering, so your results may be better.The software is kinda clunky though, so while I've tested it out and it's worked fine, I've mostly ended up using an old digital scope that I bought off of ebay for about $200. However, I do still keep it around in case I need a logic analyzer.

author: HB9EVI
author_rank: Frequent Contributor
timestamp: June 16, 2019, 06:12:32 pm
content: for 200 +/-50 bucks I'd give it a try since it's open sourcegood work I'd say if you're not so experienced with assembly

author: prasimix
author_rank: Unknown
timestamp: June 20, 2019, 10:16:05 pm
content: The crowdfunding campaign just started:https://www.crowdsupply.com/scopefun/open-source-instrumentation

author: james_s
author_rank: Super Contributor
timestamp: June 20, 2019, 11:00:40 pm
content: Yeah I think it's been said already that $200-$250 is about the right price point for this thing. That's cheap enough that it has something to offer over more polished commercial products.

author: dejanpri
author_rank: Newbie
timestamp: June 23, 2019, 08:18:18 pm
content: I am reading this with interest and I just wanted to say, because you seem to be very focused on the price of ScopeFun...$250 is about right for the "old" version of ScopeFun which was released few years ago. The "new" version of ScopeFun which is currently available on Crowd Supply is an improved design with higher specifications, so the price is also higher. If you check theScopeFun BOM fileon gitlab, you can see that there are more than 100 different types of components used and some of them are quite expensive.And if you are comparing ScopeFun with other commercially available oscilloscopes, you should check all specifications, because a lot of times there are limitations which other manufacturers usually hide in small print.But anyway, If you focus only on price, then you are probably missing the main idea of ScopeFun. It's not trying to directly compete with other commercially available oscilloscopes in terms of price, but more to build an open T&M platform which can be fully customized.--Dejan,ScopeFun

author: james_s
author_rank: Super Contributor
timestamp: June 24, 2019, 05:24:00 am
content: Sure but in the end it all comes down to price for most people, price is king, and virtually all successful open source projects are successful because they are either cheaper than comparable commercial products or they do something unique that is not easily done by commercial products. I cannot think of one single successful open source project that costs as much or more than a COTS product of similar capability. Only a very, very tiny number of people have the skills and desire to modify and customize their test gear. Most people who have the skills to do that are going to prefer to spend their time using their test gear to accomplish other things rather than customizing their test gear.I use quite a lot of open source stuff, both software and hardware, always because it's either cheaper than commercial equivalents or it's so niche that a commercial equivalent doesn't exist.

author: OwO
author_rank: Super Contributor
timestamp: June 24, 2019, 05:28:53 am
content: Well price is kind of important because >$500 is a major investment and most people simply can't afford/can't justify the spending...

author: wilfred
author_rank: Super Contributor
timestamp: June 24, 2019, 05:57:18 am
content: Quote from: james_s on May 18, 2019, 07:13:57 pmYou'll have to tell me why you expect open source to be cheap (or free). Free has two meanings in the world of open source. Not all commercial products are polished, complete or supported very well or for very long. Eg smart TV's or really any device that requires firmware. Open source projects are not necessarily half-baked either. I'm assuming by half baked you mean subject to continuing change. Which would be unfair because it is in essence the aspect of open source that appeals to those not strictly motivated by the free price tag.

author: OwO
author_rank: Super Contributor
timestamp: June 24, 2019, 06:05:10 am
content: I had a quick look through the BOM and it looks very un-optimized; why do you need both 1.25V and 1.8V voltage references? 1.8V is also an uncommon voltage (1.25V and 2.5V are the most common). What is that soldered through hole jumper for? No way to route a signal (this is a 6 layer board??) or use 0ohm smd jumpers? There are both 0402 and 0603 10nF caps, get rid of one. Why both 0603 and 0805 0ohm jumpers? You have 4 different voltage references and 4 different TVS diodes, surely this can be reduced? There is also what looks like 4 different op-amp types with similar specifications.From the BOM it looks like someone designed this with no consideration of manufacturing or parts sourcing. The parts choices in general is also quite strange, niche and uncommon parts are used for very ordinary and common applications. I'm sure there is huge leeway in cost reduction without compromising quality. Even the open source 3GHz VNA designs have no more than 60 BOM lines.

author: OwO
author_rank: Super Contributor
timestamp: June 24, 2019, 06:08:03 am
content: ...and the elephant in the room is that this is a 6 layer board when it really should be 4 layers. Every single open source VNA design I've seen are 4 layers...I don't think the open-sourceness has anything to do with the price, it's all about design optimality and (trying to) do more for less, exactly the same thing in the closed source world.

author: dejanpri
author_rank: Newbie
timestamp: June 24, 2019, 03:17:18 pm
content: OK, you are looking at BOM and you are starting to see why it costs so much...Actually a lot of time and work was invested into optimizing BOM, and let me assure you that every component is there for a reason:- 1.8V ref. is used for control DAC's and 1.25V ref. is for AWG DAC. We could use only one, but this would reduce precision for AWG and also increase noise- there are no wire jumpers on PCB, you are probably looking at heatsink anchor- 10 nF 0603 capacitors are used on digital inputs (more resistant to ESD), others are used for HF decoupling- regulators+tvs diodes are located on different input blocks and for different reasons - protection requirements for analog front end are not the same as for ADC or digital inputsAlso, there are no niche and uncommon parts, all parts are available at mouser, except FPGA and heatsink assembly.If you need to reduce the costs as much as possible (and are willing to make some compromises regarding reliability and performance), then your suggestions could make sense, but even then the difference in price would be small, because the most expensive components are FPGA, ADC, DAC and high speed op-amps.4 layers??? I'm not saying it's impossible, but it would be extremely difficult to route high speed signals between FX3 <> FPGA <> DDR3 only on 4 layers and almost certainly not without blind/burried vias which costs the same as adding 2 more layers. High speed signals require a solid plane reference and more layers also improves EMI which is important for low noise.

author: OwO
author_rank: Super Contributor
timestamp: June 24, 2019, 03:31:52 pm
content: Quote from: dejanpri on June 24, 2019, 03:17:18 pmLook at my example design of 32 bit DDR3 + Zynq on 4 layers:https://github.com/gabriel-tenma-white/sdr5I'll take a more detailed look at the schematic rather than just the BOM and see if I can find any more low hanging fruit to fix.

author: free_electron
author_rank: Super Contributor
timestamp: June 24, 2019, 03:48:21 pm
content: Quote from: OwO on June 24, 2019, 06:05:10 amcopy paste of appnote designs ....

author: james_s
author_rank: Super Contributor
timestamp: June 24, 2019, 03:59:22 pm
content: Quote from: wilfred on June 24, 2019, 05:57:18 amI already did tell you, in fact it has been mentioned several times. I expect open source to be cheap because it virtually always is. I expect it to be cheap because it usually is not quite finished, not quite as polished as a commercial product. I have to do some of the work myself, I have to do my own digging for information, I cannot simply call up the manufacture and get support.Can you point me to even one open source project that is successful despite costing as much or more than a comparable closed source commercial product? I can't think of one. If you still cannot understand why most people expect open source to be cheaper then you are being willfully ignorant.

author: thm_w
author_rank: Super Contributor
timestamp: June 25, 2019, 12:04:31 am
content: Quote from: OwO on June 24, 2019, 06:05:10 amMost of your points are valid, but, multiple packages or 0 ohm shunts? We are talking about shaving cents off of the design at that point. Its not worth the time.Going off jlcpcb prices, 4-layer pcb is ~$2.40 each and a 6-layer is $3.50. So saving $1.10 per board is somehow a big savings, considering the hours of work you'd put into it?Their goal is to sell ~100pc, so mouser prices are:KAD5510P-25Q48 $44XC7A35T-FTG256 $40 (don't see it on mouser)LTC6957HMS-2#PBF $5.49ADA4817 $5.00 x 2AD8337 $4.40 x 2MAX15053 $2.20 x 5LTC4360-1 $1.80OPA2830 $2.20If you can figure out how to save onanyof these parts its going to make much more difference. LCSC has the FPGA but not enough pieces sadly.

author: Marco
author_rank: Super Contributor
timestamp: June 25, 2019, 01:56:48 am
content: Trying to earn back the invested time takes enough margin, that worrying about a couple bucks worth of components/PCB isn't really worth it.

author: Marco
author_rank: Super Contributor
timestamp: June 25, 2019, 02:01:24 am
content: Quote from: james_s on June 24, 2019, 03:59:22 pmFor manufacturers where doing so won't just aggravate you and help very little, the prices for this level of functionality will be more expensive.

author: AndreZheng
author_rank: Contributor
timestamp: June 25, 2019, 02:13:27 am
content: ;DI can help give you a quote for this chip. The XC7A35t-2FTG256C FPGA costs around 15$, but this is the price from China local vendor.

author: OwO
author_rank: Super Contributor
timestamp: June 25, 2019, 05:57:54 am
content: Reducing BOM lines isn't saving cents, it can save up to $10 per unit on assembly based on various quotes I have gotten. Non-optimal parts choices add far more cost, because I see a large portion of the cost of the design is in the little things. I see ~$20 in ESD protection alone, there must be a more effective way of doing input protection. The choice of main system components may not be optimal either, for example I have seen far cheaper ADCs with similar specs, and if you are buying FPGAs from digikey you are getting ripped off (it's not too bad for prototyping but you don't want to do that for production).

author: OwO
author_rank: Super Contributor
timestamp: June 25, 2019, 06:02:43 am
content: QuoteReplace with AP3429 ($0.168 on mouser @100pcs). Same specs, 1/10 the price. Also saves you from the PCBA cost associated with a stupid package.

author: dejanpri
author_rank: Newbie
timestamp: June 25, 2019, 12:36:45 pm
content: Quote from: OwO on June 24, 2019, 03:31:52 pmI see you are using a larger footprint Zinq in your DDR3 design. Now try to add 2x10 bit ADC, 12-bit DAC, 12-bit digital GPIO, 32-bit GPIF FX3, etc... and 4 layers aren't enough anymore. But as I said, even if you could do it, I would be concerned about EMI.

author: dejanpri
author_rank: Newbie
timestamp: June 25, 2019, 01:15:32 pm
content: Quote from: OwO on June 25, 2019, 06:02:43 amNice find, this could probably work

author: dejanpri
author_rank: Newbie
timestamp: June 25, 2019, 02:31:56 pm
content: @james_s, but why do you think that ScopeFun costs more then a comparable closed source commercial product? I think you should check again...

author: james_s
author_rank: Super Contributor
timestamp: June 25, 2019, 03:03:47 pm
content: Quote from: dejanpri on June 25, 2019, 02:31:56 pmI didn't say it did, at $750 I suspect it does, at a lower price perhaps not, I haven't really checked. I was simply responding to the absurd "why would you expect open source to cost less?" question.

author: nAyPDJ
author_rank: Contributor
timestamp: June 26, 2019, 01:12:01 am
content: @dejanpriOne thing I', curious about is why write your own scope software from scratch? I've taken a bit of a look at Sigrok, and it seems to me like extending that would have save some work, especially with how constrained your project is in manpower.

author: thm_w
author_rank: Super Contributor
timestamp: June 26, 2019, 01:21:17 am
content: Quote from: OwO on June 25, 2019, 05:57:54 amSo you are telling me adding a single BOM line item, increased the assembly quote by $1+ per board?Changing this quote from 100 unique parts per board to 110 increased the cost by 40c per board, or 4c per component:https://www.pcbway.com/quotesmt.aspxThis page went up 16c per board or 1.6c per component:https://www.7pcb.com/PCB-Assembly-Quote.phpQuote$20 ESD ICs is valid place where money could be saved. You might risk additional returns, hard to say without looking at the design.Yes ADC/FPGA is where the big money is, as we've established.

author: dejanpri
author_rank: Newbie
timestamp: June 26, 2019, 11:22:43 am
content: Quote from: nAyPDJ on June 26, 2019, 01:12:01 amProbably the main reason is to have more flexibility with adding new features and also to achieve better performance. Pulseview is OK for basic stuff, but with using our software we can have features like dedicated threads, OpenGL rendering (3D view, virtual persistence) and other hardware control features like sever mode, Python API.

author: bloguetronica
author_rank: Frequent Contributor
timestamp: July 28, 2019, 03:09:36 am
content: Well, it is a good scope, with its price perhaps on the high price. But after all it is an open source project, and I think one can make if for around $300, sourcing some parts from Chine (PCB and some components).Some may say that the scope is a bit limited, but without this project, there wouldn't be a decent started DIY scope at all. Many DIY projects involving scopes just don't cut it for me (some are not even projects, while others are laughable attempts). This one works as intended, looks professional and the software runs great. I tested the software part, BTW.What more do you expect?Quote from: 2N3055 on May 18, 2019, 08:56:44 pmNo, just no. No, and no, and no.Just because a project is open source hardware, doesn't mean that the product or its components should be given for free. "Open" means free as in "free speech", not as in "free beer".Open source software has costs too. It costs energy from volunteers that develop the software, and many volunteers end up being burned out, by the way. Some open source software companies have profits: they don't live from hopes and dreams.And no, you are not financing a hipster. You are only having a freeloader stance. You think you have to create a mark in the world, reinforcing your "progressive" (aka, regressive) ideas. And then calling "hipster" to people that you don't know.Doesn't fly well. Your post is just a big no, and deserves no further comment. Try again.Kind regards, Samuel Lourenço

author: 2N3055
author_rank: Super Contributor
timestamp: July 28, 2019, 08:20:14 am
content: Quote from: bloguetronica on July 28, 2019, 03:09:36 amNo you can't make it for 300 USD, because simple hobbyist cannot solder BGA, and parts are very expensive.And saying it "works as intended, looks professional and the software runs great. I tested the software part, BTW." means nothing.It is not a open software, it is a scope.Go back and read what i wrote, again and again until you get it.And then, if you already didn't, go and buy one from the crowdfunding campaign, with your own money.Just so you are not a bigot, gallantly trumpeting virtues of open source scope to absolute beginners and other people that doesn't know better, and giving them advice to spend their only hard earned 650 USD on something that is just a promise right now.OP asked a question to a forum. Is this a good deal for the money and effort ? No it isn't.At this point it doesn't even exist. Few days ago they already started extending goals...So no, if the question is "Is this a good deal?". It's not, not even close. If it exists in a year, and if it works, then, than we will see..As for Open source hardware, it's you that has it wrong. If it costs a lot it's not free.It's not Stalin or Hitler that forbids many users to have some piece of T&M equipment.Mostly it's the price that denies them that "freedom".So, yeah, as in "free speech" we can talk until next year how great it is that we are "allowed" (free) to be able to get most sophisticated scopes from Keysight, R&S, etc etc...But because of the price not many people can. They just can't have it, period.So now we have this thing. It is not even made (it doesn't exist yet), it is as expensive as pro made equipment that does work, it has mediocre specs (does many things but none really well), and those specs are still just wishful thinking because it yet has to verified it really does achieve those specs(or works at all), but it's awesome because they published schematics.Really?This is engineering forum. I don't believe in Open Gods(R), or any kind of cults.All I say is based on facts.I don't accept "but it is different because Open something....". It's not.What you do with your own money is your problem.Giving advice to other people based on your religious/political/activist beliefs is a dick move.Open Source is and activist/political movement, and not based on real life facts most of the time, apparently.Whoever wants to do it, good luck, I'm happy for them. But vice versa, people that think differently have a FREEDOM to see things differently.Best regards,Sinisa

author: bloguetronica
author_rank: Frequent Contributor
timestamp: July 28, 2019, 11:30:37 am
content: Quote from: 2N3055 on July 28, 2019, 08:20:14 amThanks for showing me that I've understood you clearly.Anyway, I only read half of your... and, and then. Why bother? You come here talking about politics in an electronics forum. And then you state that if it not free it shouldn't exist (yeah, like you were a dictator, or entitled to be one). I'll just ignore you from now on. Good riddance!P.S.: If you have read the forum, you could get the idea that someone here has already built the first version of this scope for $239.38 . Your argument doesn't stick (unless all you really want is for someone to buy you all the parts for free - and, of course you do).Kind regards, Samuel Lourenço

author: 2N3055
author_rank: Super Contributor
timestamp: July 28, 2019, 01:41:09 pm
content: Quote from: bloguetronica on July 28, 2019, 11:30:37 amYep, you ARE the face of Open Source mentality...Listen, really, I'm happy for you or anybody else to do anything you want, provided it doesn't break law and don't screw up other people.Making things from kit is not new, schematics published with free use clause are nothing new.But some Heatkit scope made from kit years ago is not to be confused with Tektronix scope from same era. Or then cheap Hameg, that was pro made instrument.And that scope made from kit was surprisingly useful, and was worth it's (low cost) money.It's just not to be compared to pro instruments.But if you call it Open Source, and suddenly you cannot talk about it from a technical merit standpoint.If it's O.S.H. it doesn't have to be cheap, good or lately even exist for people to start summoning on squares and sing songs of salvation by O.S.H.C'mon.From the bottom of my heart, I wish you to do with your life whatever you please. But if your thing is to dress as Mickey Mouse and go to office like that, you have a right to do so. Just keep in mind that other people also have their right to have a good laugh when they see you.That applies both to you and me.So let me repeat what I said before and you (conveniently? ) didn't see: OP said that he has limited money and asked would this be a good deal as scope, generator and such. He wanted to buy assembled board because soldering BGA-s by hand is daunting task and requires equipment. Answer to that is no, it is not a good deal, to the point it doesn't exist yet. Repeating it's O.S.H. doesn't change anything regarding initial question.I also said (also was overseen) that if someone will go with it for O.S.H. reasons, as a learning experience and fully aware the costs (money and time) than it would be great..I said it was nice project and complimented authors..And as I said, when(if) they ship and someone actually tries to use it, and it proves to be good then it will be triumf of Open Source Hardware. I really wish they succeed.We'll see.But I don't plan to support them with my money or time. I see no benefit. My opinion and decision.If you do you should, and everybody else based on informed decision. Your and everybody else opinion and decision.Hell, I wish I was the only person that doesn't support them, so they can be successful..Have a good day,Sinisa

author: bloguetronica
author_rank: Frequent Contributor
timestamp: July 28, 2019, 03:52:35 pm
content: To all who might concern.I do not represent OSH in anyway. In fact, I'm burned out of being in the giving side, without merit, recognition, or money. So, now instead of just doing electronic projects for a hobby, I'm also participating in commercial projects. And perhaps I'll drop the towel on the former (because I'm tired of forumistas here wanting stuff from me, for free, and then suggesting that I could shave a line from the BOM or source inferior, dodgy components - you can read discussions regarding this from years ago).In fact, I have less motivation to give to the OSH, and I find it more motivating to do projects that get me money.So, I have two choices:- Continue with OSH projects that are complex, challenging, that I like to do for fun, spending money on quality components and without receiving any merit, or...- Give priority to my paid, commercial and easy to do (almost trivial) designs, as a freelancer.Of course, I'll take the second choice any day, without blinking. I do OSH projects just for fun. Releasing them to the public is not a priority at all (I release then whenever I feel like, delayed and all - the same goes to my videos on YouTube). I don't give much of a crap. That is what ungrateful people and freeloaders can expect of me. Like it or not, I don't care.And that is why I'm grateful to whoever created this oscilloscope. Because I know how hard it is to design the software and hardware, and because the creator now has to face the judgement of ungrateful bastards.Kind regards, Samuel Lourenço

author: nigelwright7557
author_rank: Frequent Contributor
timestamp: July 28, 2019, 09:41:49 pm
content: Quote from: prasimix on May 17, 2019, 09:02:33 amMaking one off will never compete with a manufacturer making hundreds or thousands.Its easier and better to buy something pro made and designed and has been out there a while to get rid of the bugs and get some cred.

author: excitedbox
author_rank: Regular Contributor
timestamp: August 01, 2019, 12:21:17 am
content: 1. This thing is waay too expensive for what it offers. You can almost buy a MSO5000 and unlock it to a +$3000 scope for that price.2. If Volunteers are paid they are not volunteers.3. Open Source does mean free as in free beer recipe. It means you give all the designs and code for free. Yes you can charge for hardware and assembly for a finished device that you ship and you SHOULD EARN A PROFIT ON THAT but it needs to be reasonable.If the parts are around 200 (for low volume) and assembly brings it up to 250 then you can charge 300 MAYBE. At that price though your scope is already being beat out by several other USB scopes. That is why you should be looking at making 500-1000 at once and get YOUR COST down to increase your margins.I like the project and have seen it several times but the price is WAY out of what is reasonable for what you offer. You are trying to pull the same profit margins as rigol and keysight but they offer Gs/s. Calling it Open Source will just get you backlash from the community at that point.Open Source Projects are meant to change the status quo not finance your start up. We don´t need more of the same as what the industry delivers with worse features and bug riddled, unproven projects that disappear because the developers are in it for the wrong reasons.I actually came here tonight to post asking why there are no good open source alternatives since the parts are not what make scopes expensive. It is the software and upgrade options being tacked on. We have tons of huge open source software projects so it should be possible to get the price down by doing the same with oscilloscopes.PS. ANYONE can solder BGA with a toaster oven and a stop watch. Some of my first soldering projects I soldered LGA chips.I would buy a Rigol DSO1052 and DSLogic add in a $80 kkmoon signal generator and be under 450 and beat every feature of your scope 2-4 fold.EDIT: People who have built them themselves are saying they paid 90-120 for the parts. That makes it even more of a cash grab. That would mean a nice 60k profit on a 100 units. Laughable what these guys are doing and calling it open source. Same as that other 600 "Open Source" scope that sells you every option extra and only open sources an absolute basic scope firmware.

author: nigelwright7557
author_rank: Frequent Contributor
timestamp: August 01, 2019, 01:02:31 am
content: I use a £10 usb scope off ebay and a £25 second hand sig gen.Had them both for about many years !$700 really ?

author: coromonadalix
author_rank: Super Contributor
timestamp: August 02, 2019, 05:35:57 am
content: I think the OP has all the answers now ... it should stop here.

author: Marco
author_rank: Super Contributor
timestamp: August 02, 2019, 03:56:05 pm
content: Somehow I think people are just trolling now :/

author: bloguetronica
author_rank: Frequent Contributor
timestamp: August 02, 2019, 05:19:48 pm
content: Yes, they are. I see statements like, "OSH is/should be free as in free beer". But the OSHWA definition tells a completely different story:https://www.oshwa.org/definition/Anyway, good scope, bad scope, recommend, don't recommend... That is the subject here. I already left my opinion.Kind regards, Samuel Lourenço

author: ratatax
author_rank: Regular Contributor
timestamp: August 08, 2019, 03:01:43 pm
content: Well I haven't read all this thread but I think usually open source projects are for people that like to get hands dirty, people who wants to contribute to the project or are interested into designing their own scope.For end users that just want the best scope for the best price, it's not a good idea.

author: ratatax
author_rank: Regular Contributor
timestamp: August 08, 2019, 03:15:22 pm
content: Quote from: excitedbox on August 01, 2019, 12:21:17 amThat's totally unrealistic. If you already designed a product, you probably know that something with a $200 BOM cost is more likely to cost $1000 than $300...

author: taydin
author_rank: Frequent Contributor
timestamp: August 08, 2019, 03:46:37 pm
content: If you want to build this scope from components, chances are something won't work, and you will need a scope to troubleshoot. So if you don't have a scope and are building this from components just to HAVE A SCOPE, you are taking a big risk. Chances are very high that something won't work, nobody is so lucky that a hardware at this level of complexity will "just work".So, this ScopeFun only makes sense for educational purposes. You will build a fairly complex circuit from scratch, you will encounter issues, fix them and learn a lot. Or you will buy it ready built, and write new software or new FPGA code for it, and learn a lot.But is it a good deal to be a beginner's first scope? Nope.

author: bloguetronica
author_rank: Frequent Contributor
timestamp: August 08, 2019, 10:53:30 pm
content: Quote from: ratatax on August 08, 2019, 03:15:22 pmYup, I agree. Unfortunately, many people nowadays don't value someone else's work, and often expect things for free.Kind regards, Samuel Lourenço

author: james_s
author_rank: Super Contributor
timestamp: August 08, 2019, 11:31:33 pm
content: The issue there is we can buy hardware from China all day long at absurdly low margins so that creates an expectation for that sort of prices.Expensive botique stuff has its place but the market is tiny. It's easier to do with things that are "artistic" or audiophool gear.I mean can anyone here honestly say they'd fork out $700 for an open source project like this when they could get something offering superior performance for much less?

author: excitedbox
author_rank: Regular Contributor
timestamp: August 11, 2019, 03:06:54 pm
content: That is why China is wiping the floor with the US, greed. If you need to do work once and can sell it millions of times then you cans sell it for 300 and still make a ton of money. Taking the raspberry pi for example which has sold 10 million+ units would have made the designers a good amount of money with very slim margins. Obviously a scope isn´t going to sell nearly as many so the margins need to be bigger. Even if the designers only get 25 cents for each pi sold their hourly rate would be insane. Look at BOM of the pi and other projects none of them are near 500% profit margins.If you can sell the scope for $300 and sell 100X as many you will make more money than selling a coupe hundred to a small enthusiast crowd for 1000. In addition economies of scale kicks in and your BOM cost goes down by about half going from 100 to 1000s so now you are not making 100 profit but 200. Even if you spent 10,000 hours developing this thing or about 6 people working full time for a year would each be making $20 an hour with those margins. Selling 5000 takes that profit to $100 an hour each. Obviously there are also other costs involved but a decent scope will also sell a ton more than 5000 units especially in the budget price range.Also calling them volunteers while collecting 500% profit margins is an insult.My biggest problem is that the OP is almost certainly related to the project and not really asking for advice. It looks like a thinly veiled attempt at getting eyes on this project. Certainly would be how I would go about it and I have done that with websites I made to get the first few users to look at it.

author: Marco
author_rank: Super Contributor
timestamp: August 11, 2019, 09:31:29 pm
content: They sell it with no warranty or support ... a project like say Red Pitaya has far more support than pretty much anything out of China. Also it's able to sell the hardware at quite a large markup, most of which is actually necessary.I find it impossible to believe that with something like Red Pitaya already out there and having long term success that people are honestly quibling over the bit of margin here. There is a market out there for these kinds of projects and the people working on them would like to earn a bit of their initial time investment back on the first batch.

author: maginnovision
author_rank: Super Contributor
timestamp: August 28, 2019, 05:38:14 pm
content: For the price it's a hard pass for me. I'd get an mso5000 first. If I've got 750 to blow on unknown hardware software I've got another 250 to buy from experienced engineers This thing isolated or not, I didn't see anything about it.