Picoscopes - Page 1
Forum section: electronics / testgear

author: nbritton
author_rank: Frequent Contributor
timestamp: September 20, 2015, 11:22:56 pm
content: What are you're thoughts on the Picoscope line of USB scopes?https://www.picotech.com/products/oscilloscope

author: nbritton
author_rank: Frequent Contributor
timestamp: September 20, 2015, 11:39:12 pm
content: In particular I'm eyeballing the PicoScope 3405D MSO:https://www.picotech.com/oscilloscope/3000/usb3-oscilloscope-logic-analyzerSpecs:4 analog + 16 digital channels100 MHz analog bandwidth1 GS/s real-time sampling256 MS buffer memory100,000 waveforms per secondArbitrary waveform generatorUSB 3.0 connected and poweredMac and Linux compatible.Anyone have experience with their software?

author: nctnico
author_rank: Super Contributor
timestamp: September 20, 2015, 11:52:00 pm
content: USB scopes are tedious to use. I have used a Picoscope before and didn't like the 1-2-5 full scale ranges. On a real scope you have 8-16-40 full scale ranges (volt/div * 8 ) which work nicely with 3.3V and 5V logic signals, +/-10V, +/-12V and +/-15V power supplies.edit: remove unintended smiley

author: pyroesp
author_rank: Regular Contributor
timestamp: September 21, 2015, 12:13:05 am
content: I've used the 2203 a few years back, still have it somewhere. I needed one asap and didn't have the funds nor the space for a bench scope.I do regret buying it.Software was ok and very easy to use, just the scope I had was just bad, shitty BW, freq gen at 1Vpk or something like that.My laptop at the time was not the best either, and running the picoscope software it would get a bit slow.I think you can download their software from the webpage, have a play with it.

author: Maxlor
author_rank: Frequent Contributor
timestamp: September 21, 2015, 12:52:10 am
content: We have an older Picoscope at work, and while the hardware is nice, it barely gets any use because setting up the rigol is just quicker, what with not having to wire everything up and find the software. Plus, the software didn't appeal to me that much, I didn't find it all that intuitive.However: looking at the page linked above, it seems they have a new version of their software out which looks better and is finally cross platform, plus it still seems to support their older models. I think I'll try that one when I have some spare time.

author: nbritton
author_rank: Frequent Contributor
timestamp: September 21, 2015, 01:28:35 am
content: Quote from: nctnico on September 20, 2015, 11:52:00 pmYou can make a controller box using simple digital encoders.

author: dadler
author_rank: Unknown
timestamp: September 21, 2015, 01:35:51 am
content: I have the entry level model. I never use it. The software is painful to use and does not compare to a real scope with hardware controls.PicoScopes seem to be used primarily by the automotive industry. I bought mine for automotive use, and quickly realized it was not a good fit, unless one already has a laptop down in the vehicle. Even then, it's fiddly and non-intuitive to use.My Rigol DS1054Z has now become my beater automotive scope, and it works almost perfectly for my use case. If you need to use the scope with the vehicle in motion, and do not have access to mains power, the PicoScope may have an edge--although I would probably just find a clean 12V DC->mains inverter first and use my Rigol.Edit: I see above that someone mentioned that the Pico software is cross-platform. That might be sort of true, but the Mac version is missing almost all of the features of the Windows version. It's way stripped down.

author: nbritton
author_rank: Frequent Contributor
timestamp: September 21, 2015, 01:38:00 am
content: Quote from: Maxlor on September 21, 2015, 12:52:10 amBut for someone who is a hobbyist would that really be a major issue? Also I have no predilection since I've never used a modern DSO, the only scope I've ever used was an old analog Tektronix 2213A.

author: rx8pilot
author_rank: Super Contributor
timestamp: September 21, 2015, 01:38:04 am
content: Not sure why no one makes a control panel for USB scopes. They have to deal with trivial IO speeds just for buttons, encoders, and LEDs. The pro audio/video Industry has been doing this for years and its awesome.Big processing is physically seperated from human interface. USB modular scopes could really be great with only minor effort.Sent from my SAMSUNG-SM-G890A using Tapatalk

author: dadler
author_rank: Unknown
timestamp: September 21, 2015, 01:47:38 am
content: Quote from: nbritton on September 21, 2015, 01:38:00 amI am just a hobbyist, and I find that hardware scopes (I have the DS1054Z, DS2000A, DSOX3000T--yeah I like toys) are just so much easier to use when working on real circuits/projects.With dual monitors, my computer usually has a PDF of a datasheet, or a web browser, or EAGLE/LTspice open. I have my scope up and running at the same time, tweaking while working on my projects. I think that as a hobbyist in particular, it is better to have a dedicated computer available for research that is not also your scope interface.

author: rs20
author_rank: Super Contributor
timestamp: September 21, 2015, 01:53:26 am
content: I'm tempted to buy a Picoscope 3000 series with the built in MSO because:-- It has the logic analyzer functionality built-in, and time-correlated with the four analog channels as well.-- It's widely accepted that logic analyzers are better on PC, right? [Interesting to speculate why the story is sooo different for analog vs digital...]-- I want the ability to stream a large stream of data being stored on disk for the continuous, "infinite" record feature. I.e., I'm planning to use it as a general purpose ADC.It's important to note, though, that I'm not expecting it to supplant my Rigol DS2000 series.Am I missing a cheaper alternative to achieve my list of goals? I can't find a cheaper way of getting a 4-channel 100 MHz ADC for my computer full stop, let alone all the other features.

author: nbritton
author_rank: Frequent Contributor
timestamp: September 21, 2015, 02:53:30 am
content: Quote from: rs20 on September 21, 2015, 01:53:26 amYes the MSO is the killer feature on this for me too. I'm having a hell of a time finding a decent USB logic analyzer that has trigger out capabilities, without trigger out you have no way to time-correlate digital events with the analog channels on your DSO.Also it has a built-in waveform generator that can replay a waveform when an event is triggered. The logic analyzer can also be programmed to trigger the scope when any or all of the 16 digital inputs match a pattern.The box has a 256M buffer (512M on the 3206D) and can sample at 1 GS/s all the way down to 50ms.

author: nbritton
author_rank: Frequent Contributor
timestamp: September 21, 2015, 03:11:30 am
content: Quote from: dadler on September 21, 2015, 01:47:38 amI have 3 notebooks and 3 tablets in my apartment right now. If I did buy a picoscope I would have a dedicated system for it. In fact, I would probably assemble some embedded single board computer (MinnowBoard MAX: $146) into a box with some digital rotary encoders, buttons, and levers.

author: dadler
author_rank: Unknown
timestamp: September 21, 2015, 03:49:09 am
content: Quote from: nbritton on September 21, 2015, 02:53:30 amYou can connect the trigger out of your scope to one of the digital inputs on a logic analyzer like the Saleae Logic, and trigger the logic analyzer on it. Then you can correlate signals. The trigger options on the entry-level USB logic analyzers are limited anyways. The best feature of the Saleae is that you can easily write your own decoder plugins, just extend a C++ base class.Maybe I am spoiled, I have the MSO option on my DSOX and find the integrated interface, with real hardware controls, unbelievably easy to use. There is a reason that professional design engineers use real oscilloscopes and not these all-in-one USB units. Nearly every all-in-one unit is ok at most things, and not particularly good at any one thing. "Jack of all trades, master of none."I would think long and hard about investing serious cash in a USB oscilloscope, especially if you don't have much experience with DSOs. You may regret it. There is a reason they are much, much less popular than traditional oscilloscopes. They aren't necessarily some hidden gem the rest of the world is missing out on.Download the PicoScope software (it runs in demo mode with fake signals) and get a feel for it. It's not bad software, but it was clearly designed by engineers and not UI/usability designers. Don't get me wrong, PicoScope is a legitimate company that makes quality products. However, Pico products seem to be primarily used in certain niche applications--where a USB tool really is necessary.All of this is just my opinion, if you are dying to have a USB scope, by all means Pico makes some of the best ones. Also consider the NI VirtualBench:

author: nbritton
author_rank: Frequent Contributor
timestamp: September 21, 2015, 04:37:33 am
content: Quote from: dadler on September 21, 2015, 03:49:09 amOk. What do you do if you want to trigger on a digital pattern? I can easily envision a scenario (i.g. a glitch) where you would want to trigger on a digital pattern so that you could look at what's happening on the analog channels when that event occurs.

author: vk6zgo
author_rank: Super Contributor
timestamp: September 21, 2015, 04:47:59 am
content: Quote from: nctnico on September 20, 2015, 11:52:00 pmI did a bit of a "double-take",as I don't normally think of a 'scope in terms of "full scale",but I see what you mean.A display 8 divisions in the vertical dimension gives you reasonably sized divisions,& most commonly encountered voltages use sufficient divisions to be easily observed.

author: Electro Fan
author_rank: Super Contributor
timestamp: September 21, 2015, 04:56:34 am
content: Quote from: nbritton on September 21, 2015, 02:53:30 amFrom an older post but I think Intronix might make a trigger output available or otherwise provide info on how to do it if it's requested.http://www.edaboard.com/thread146631.html"Also I found the guy who runs the company (Harrison) to be very helpful whenI had some queries about the availability of a trigger-out signal, or whether theFPGA could be tweaked to give a trigger-out.He said that he'd updated the PCB to have a trigger-out connector, and that ifI opened the case I could cut a little slot and solder in a 2-pin right-angledheader. There is a fixed cycle delay on the trigger-out (as the trigger logic isheavily pipelined to sustain the 500Mhz sample rate) but I just wanted it totrigger a DSO near the area of interest, it worked very well for me."http://www.pctestinstruments.com/Supports both timing-mode and state-mode500MHz Timing-Mode (Internal Clock)200MHz State-Mode (External Clock)

author: dadler
author_rank: Unknown
timestamp: September 21, 2015, 07:58:06 am
content: Quote from: nbritton on September 21, 2015, 04:37:33 amMost simple USB logic analyzers, like the Saleae, don't let you trigger on patterns like that (assuming you mean pattern, as in decoded data). They trigger on edges, and then dump a ton of data on the USB line to the PC. The big data stream is then post-processed and you can search through it. These sorts of logic analyzers are meant for mass data collection and post processing, not real time decode/triggering.In this scenario, you would trigger with the scope (it has much, much better trigger abilities), and then search through the digital data you collected/decoded with the analyzer. The Saleae can (and will) stream so much more data than your scope could ever buffer.I can do what you are describing on my MSOX3000 (and both of my Rigols, for that matter). I don't think I ever have, as "glitches" are typically analog in nature, and I would just trigger on the glitch?

author: rs20
author_rank: Super Contributor
timestamp: September 21, 2015, 09:30:42 am
content: Quote from: dadler on September 21, 2015, 07:58:06 amI can't speak for the OP, but my Rigol DS2000 series has "pattern" trigger and there it is defined not as a pattern across time, but a pattern across channels. For example, using the "pattern" trigger, you can ask to trigger when CH1 is high AND CH2 is falling edge.

author: German_EE
author_rank: Super Contributor
timestamp: September 21, 2015, 10:01:52 am
content: I have been running a Picoscope 3206 in my home workshop for years, it has good and bad points:GoodI really like the big screen on the PC because these days my eyesight struggles on some of the tiny letters on a standard scope screen.The unit has held its calibration over the years despite some rough handling.The slow sweep speeds turn the scope into a two channel chart recorderThe basic multimeter is useful and of course is two channelDespite being a unit that is years old it still runs the latest software from PicoscopeYou also get a basic spectrum analyzer using the FFT function.Lots of support from the Picoscope community and the support staff DO monitor the forumsBadThe triggering is not so good and I ended up building my own trigger circuit that plugs into the front .The maximum input at the BNC connector is 20V which is maybe a little low.X-Y mode can give some very strange results depending on the frequencies usedNo x10 probe detection

author: D3f1ant
author_rank: Frequent Contributor
timestamp: September 21, 2015, 06:45:06 pm
content: I think others have covered this pretty well. I own a 4ch 5000 series with loads of memory (512MB). You need loads of memory on a USB scope because a pc can't process or display data in real time so scope has to be able to buffer everything, the more memory the better.Glitch spotting is harder because you will will never 'see' it like you would on a traditional scope with >100k (or 1M on an keysight 3000/4000). You just collect loads of waveforms and then review them if suspect glitches, similar to enabling segmented mode on a traditional scope. Persistence mode does sort of let you see glitches so can then set up a trigger etc, it's just more cumbersome.One very good feature is decoding, pico scopes can decode pretty much anything, and decoding and all software updates are free. A 10 year old picoscope still runs the same software as current models, you get the features your hardware is physically capable.At the end of the day, there is probably, nothing you can't do on a picoscope that you can on a traditional scope (once you learn the quirks) For the money, you get a lot more scope/features and none of that licenced software/feature bullshit.I still ended up buying/going back a standalone scope on my bench, but I keep the picoscope and still use it regularly because of the decoding and portability.And you don't really miss knobs as much as you might think, you can bind keys to basically anything in their software.

author: nctnico
author_rank: Super Contributor
timestamp: September 21, 2015, 07:08:25 pm
content: Quote from: dadler on September 21, 2015, 07:58:06 amAt some point you just need a real logic analyser. A used Tektronix TLA700 series is quite affordable (in the Intronix Logiport territory) if you have some patience. A real logic analyser has a programmable trigger statemachine which can trigger on the craziest conditions. You can use event counters, timers, etc to build an if-then-else tree using input conditions, time-outs and event counters. Not trivial to use but sometimes you just need extreme power to solve a problem.

author: Howardlong
author_rank: Super Contributor
timestamp: September 21, 2015, 08:26:49 pm
content: Over the years for USB scopes I've had a Picoscope 2000 series, a BitScope BS50 and the Analog Discovery.The Picoscope I used about three times before it was relegated into a drawer for several years, after which I sold it. The BitScope I still have, I bought it to use on the road, but the software is awful, and I haven't used it since receiving the Analog Discovery six months or so ago, which is the only USB scope I've ever used frequently, it's feature packed and the software is slick, bug free, performant and simple to use.It's not to do with screen real estate either, I run three 4K monitors on my bench setup, and the USB scopes remain in the drawer.While I can see the attraction of USB scopes, far more often than not they end up gathering dust. The only way to find out is to try one, but if I were a betting man, I'd put a fiver on it being a disappointment compared to a real scope.