NI VirtualBench Quickie Impressions - Page 1
Forum section: electronics / testgear

author: Isaac000
author_rank: Contributor
timestamp: July 02, 2015, 07:31:24 pm
content: For those not really familiar with it yet, some key specs (hopefully no typos here...):100 MHz bandwidth1 Gs/s (single), 0.5 Gs/s (dual) sampling rate2 Analog Channels, 1 Mpoints32 logic channels + 2 clockSerial decode I2C, SPI20 MHz function generator (sine, square, triangle, ramp), 14-bits, 125MS/s updateMultimeter : voltage, current, resistance, diode, etc.3-ch DC power supply: 0-5V @ 1A, 0±25V @ 0.5A8-ch digital IOProgrammable via C or LabView API~$2500USDIf you Google around, you'll find a tear down somewhere, it's basically based around a Xilinx Zynq if I'm not mistaken. Not top-of-the-line, but good enough for many types of work. The scope portion is quite low-end in fact. The selling point is that most people will be able to use this one instrument to replace everything else on the bench. That's why we acquired it, we had a guy doing embedded FPGA work with a 4-ch Tek scope and a logic analyzer would've come in handy. Rather than spring for a fully loaded logic analyzer, we decided to give this a try, just for fun. (Yes, yes, I know many people would be able to find a decent used MSO for the same cost). However, one compact package replaced the scope, logic analyzer & the power supply. Plus as it turns out, the digital IO lines are coming in handy as well.The downside is that it doesn't really work unless you hook it up to a computer. The gamble is that everyone has a computer anyways, so it is not considered additional cost. In our case, this was true as the computer was needed for the FPGA work anyways. At most we're looking at an additional monitor.The install was super-easy, plug in the AC power and then hook up the USB cable to your Windows PC. It doesn't seem to install anything on your PC, rather, it just runs an executable located right on the VirtualBench box itself. This makes it very easy to move around to somebody else's bench. It's quite small, I'd guess it is roughly the size of "The Art of Electronics", just a bit thicker. Oh, and it is super quiet. I think it has a fan in the back, but I don't think it's turned on yet, or it's just a quiet fan. (Let me tell you, his neighbours are very happy he's no longer firing up that massive Tek scope every day).The user interface was quite intuitive, we had one of our "old guys" put it through its paces and he did not have to refer to the manual at all. This thing makes a good first impression. Every engineer wanted one for themselves! I could see shops were you could easily purchase one per engineer and then cut back on the number of shared, expensive instruments. It's also within reach of a home hobbyist as it is roughly the cost of a high-end computer or good quality racing bicycle or any number of equivalents. It is possibly ideal for many educational institutions as well, you could outfit entire labs with just these things and then have the students bring in their own laptops.We did try hooking it up to a Windows 8 tablet and that actually worked fine, although the controls weren't quite optimized for a touch screen interface. So tack on a few hundred dollars (we had an old Lenovo Thinkpad Tablet) and you get that screen you needed for this instrument.Complaints?It relies on having a Windows PC, no Linux, Mac or other alternative OS. Theoretically it is accessible via WiFi, but for some reason, you need an app, which is limited to iOS only at the current time. Realistically iPad as I can't imagine anyone trying to work the controls on a smaller device.It does look nice & clean to have one AC power cord running into the thing, but if it ran off DC (e.g. like a laptop) that would provide way more flexibility as we could easily shove this thing somewhere with a large battery and along with an iPad, I could have it run completely unwired. By the way, the WiFi seems to have unexpectedly decent range. We left it on someone's desk and by chance we happened to be scanning around for WiFi in the lunch room and we could still see this thing through a couple of walls and past many rows of cubicles.Also, what are the alternatives? Having a bench full of separate instruments may take up more space, but some people would find it easier to use a real knob than twiddling something on the screen with a mouse. Additionally having separate instruments increases flexibility (e.g. it is not possible for someone to "borrow" just the power supply on VirtualBench). And if/when something breaks, your entire bench full of instruments is gone while it's in for repairs.I'm one of those who prefer separate instruments, but for my own home use, I could see myself considering this. I don't have a large home, space is very much a premium and the small size and low noise are by themselves huge benefits in this case. Yes, I am aware that you could probably get a bench full of separate instruments for same or less cost and maybe even better performance. I did try to spec that out myself, just for fun, and it is fairly easy.However, in some parts of the world, this is not a good option. (Just to give you an example, my current abode runs ~$1000USD/sq.ft. so if you look at it that way, by not having another instrument saves me a ton of money. Yah, yah, sure you could stack things to some degree but if this thing does the job....add to that the slick design and low noise factor would keep me in the good graces of my other half.)I am not sure I see it really making a huge dent in the "pro" market, mainly because most engineers can just ask for more space and most of the bean counters are familiar with the cost of test instruments so it is not hard to ask for better, separate tools. But it is a nice toy and there are certainly cases where the specs are more than enough.

author: AutomationGuy
author_rank: Contributor
timestamp: July 02, 2015, 09:22:51 pm
content: nice device. But probably not for hobbyists.Which sampling rate for the logic channels?Do you connect the FPGA to the logic channels?

author: Muxr
author_rank: Super Contributor
timestamp: July 02, 2015, 10:01:37 pm
content: The space saving benefit is really cool. I could see this being really appealing to people who travel with their gear as well. The price is out of the hobbyist range a bit, but it's really not that bad considering all the functionality.I wonder about the usage aspects of it. You said UI wasn't bad. How's the update rate, and general latency of the controls over Wifi?edit: would like to see Dave take it through the paces.

author: mtdoc
author_rank: Super Contributor
timestamp: July 02, 2015, 10:13:38 pm
content: Ben Krasnow did a nice review:

author: NoItAint
author_rank: Contributor
timestamp: July 03, 2015, 04:20:48 pm
content: I'm a hobbyist, well I'm just starting to get back into it so call me a "Hob"and this is looking pretty good.Sure, separate discreet gear you'll get the best functionality and accuracy I bet. And yet here it all is, all in one and ready to go.And for a mere $1000 more, VirtualBench has Labview where one can do a lot of automation. So as you're piecing together one circuit you can simulate another. Seems very useful.I have to say though what's with the traces not refreshing while you move them left or right until after you let go of the mouse?They must be reading from the scope memory, they could download this to the PC in the background at least when the scope is stopped.This whole graphical interface looks very crude for what it could be. This is the only access to the VirtualBench That alone will keep this Hob from considering this.Maybe a third party GUI will come along for it?

author: AutomationGuy
author_rank: Contributor
timestamp: July 03, 2015, 04:31:46 pm
content: I have the impression its meant to be used in automation with all its interfaces. Not much need for a sophisticated GUI for an automated system.Not many hobbyists need to automate measurement at home.For that price you can get a nice scope.

author: eas
author_rank: Frequent Contributor
timestamp: July 03, 2015, 05:51:29 pm
content: These would be awesome if they'd been on the market for the better part of a decade and I could buy a used oneEven so, now that I have a new DSO, a few used DMMs and power supplies, I've started wishing for some more compact options. The Function generator I just bought is huge. Being able to replace or avoid a rack of equipment is looking better and better to me.Quote from: AutomationGuy on July 03, 2015, 04:31:46 pmI think your username is skewing your perspective. If you look at how NI actually positions it, they spend a lot of words/space on the compactness, clutter reduction, and ease of use, particularly for ad hoc exploration. Automation is at the bottom of the list, and only gets a few lines. Of course, given that it is coming from NI, I doubt its utility for small-scale automation is lost on anyone.Does anyone know if, out of the box, the software has built in support for MIDI controllers? If so, you can get all sorts of USB knobs and sliders.

author: Isaac000
author_rank: Contributor
timestamp: July 07, 2015, 12:12:56 am
content: Quote from: AutomationGuy on July 03, 2015, 04:31:46 pmI don't know about that, the GUI will do just fine for most hobbyists, in my opinion and I think that was the intended mode of operation.It does come with C API now so it wouldn't be too hard for someone to roll an alternative GUI or use it for automation without having to use LabViewFor that price, yes, you can get a much better scope pretty easily.But could you get a better scope and a better logic analyzer and a better power supply and better digital I/O and better function generator and better multimeter that all interfaces nicely to your Windows PC and takes up the space of a decent textbook and is just as quiet?Depending on NI, it could just get better and better since it is basically built around FPGA. For example, I queried them about using it for high-speed digital I/O and they said it was all easily possible, the hardware is there. It's just a matter of prioritizing what customers are asking for and updating the firmware/driver.