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I've been thinking about buying an oscilloscope for self usage. However, searching for oscilloscopes on Google reveals that they are very expensive - the cheapest I found was about $200.

It turns out, however, that my university provides a license to LabVIEW for students. I have used LabVIEW before, and know that it can be used to measure and display varies signals and measurements.

So all I need is a data acquisition card, such as this one https://www.ebay.com/itm/National-Instruments-USB-6501-Data-Acquisition-Card-NI-DAQ-DIO/153961979967?epid=153445569&hash=item23d8d9603f:g:GIAAAOSwGhRe21we

My question is whether or not LabVIEW can replace an oscilloscope for signal measuring, or if an oscilloscope is something that you just can't replace.

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    \$\begingroup\$ it is not Labview that is replacing an oscilloscooe .... it is the data acquisition card ... Labview replaces the display of an oscilloscope .... you can find free software to display the data \$\endgroup\$
    – jsotola
    Dec 14, 2020 at 17:04
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    \$\begingroup\$ Check out Hantek. I bought one less 200. \$\endgroup\$
    – user263983
    Dec 14, 2020 at 17:20
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    \$\begingroup\$ I paid $80 for a 10Mhz tektronix from the early 90's on Ebay. You don't want to use LabView...it will be much too limiting to you. \$\endgroup\$
    – Kyle B
    Dec 14, 2020 at 20:07
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    \$\begingroup\$ Have you considered a second hand scope? You can get cheap ones for around $25 on ebay. \$\endgroup\$
    – OmarL
    Dec 15, 2020 at 6:54
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    \$\begingroup\$ Have you considered a USB scope, like Picoscope, for example? They're cheaper than regular scopes, take up less space on your desk, and all the data is right there on your PC (handy for analysis and screenshots). (I don't work for Picoscope; other USB scopes are available.) \$\endgroup\$ Dec 15, 2020 at 11:15

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Sort of, but you won't be really happy with it.

LabVIEW only replaces the display end of an oscilloscope. You need a data acquisition card to take the place of the oscilloscope hardware - you know that since you've already picked out a NI DAQ.

The DAQ you picked out appears to be digital IO only, so it wouldn't be much good as an oscilloscope.

In any event, there's not a full featured oscilloscope program for LabVIEW that you could use. You'd have to implement it yourself.

A good (and fast) data acquisition card from NI would cost as much as a (low end) regular oscilloscope - and the low end scope would perform better as an oscilloscope than LabVIEW and some home grown VI.

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  • \$\begingroup\$ Just to second this, our production facility uses LabVIEW on test and calibration rigs where we need to integrate interferometers, analogue voltage measurements, and our own USB-connected gear, with some complex processing going on. We also have bench scopes, because they're better for general measurements. We even have two 20-year-old spectrum analysers, because they do a better job than anything else for very small signals embedded in noise. Using the right tool for the job is always the best plan. \$\endgroup\$
    – Graham
    Dec 15, 2020 at 8:40
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Suitable Labview acquisition cards are even more expensive than scopes.

For instance, here's one that could be used as a scope, though a lousy one:

  • Input range ±10 V, ±5 V, ±2 V, ±1 V.
  • 2 analog outputs, 16 bit, max. 500 kS/s (one channel) or 250 kS/s per channel. Range ±10 V.

I could probably live with ±10 V range, and 16-bit is better than most cheap scopes. However, only two channels at 250 kS/s mean it cannot display anything faster than audio.

Note that the price tag is 500€, which can get you a decent scope with 1GS/s (three orders of magnitude faster!) and 4 channels. For comparison, a LabView card with such specs would set you back around $10'000.

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    \$\begingroup\$ NI hardware is always expensive - we keep using our good oscilloscope in workas the acquisition device for LabView, instead of buying something dedicated - 2 channels of a few hundred MHz plus a trigger costs a small fortune just to not have a screen \$\endgroup\$
    – Chris H
    Dec 15, 2020 at 21:19
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If you don't want to use a dedicated aquisition board and only have limited requirements concerning samplerate/bandwidth/resplution/etc. you could use the audio-in to measure analog sinals. You should make sure to not exceed the audio port's ratings (which are +-1.5V if I remember right). This of course does not replace a professional oscilloscope or data aquisition cards, but it's pretty much for free .

Though you could use any programming language to read the data, LabVIEW might be a good choice if you have access and are used to it. Recording audio and plotting .wav files is straight forward in the student's edition.

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In some ways, I have a NI PXI 4462 card in a little portable data acquisition system, and it's far superior to an oscilloscope for high resolution very low frequency (DC to audio) signals. I don't love the Labview interface, though it is usable and offers features such as resampling. Once you have the data you can use whatever programs or software you like to massage the data, do Fourier transforms, spectrograms etc.

However for most general electronics work, even a cheap "real" oscilloscope such as a Rigol is much more useful. For example, if a circuit was oscillating it would not likely even be visible with a data acquisition system, but the 'scope would show it immediately.

They really do two different things. I would suggest a 50MHz or better oscilloscope as your first investment in such test equipment. If you spend a lot of time working on sensors and such like, a data acquisition system is certainly useful, but I would say an oscilloscope is essential.

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    \$\begingroup\$ @OP: The difference between a $60-ish 70 mm by 100 mm oscilloscope and a "real" oscilloscope is much much greater than the price difference. A DS1074Z even comes with all the expensive software upgrades included at base price if you buy from the right place. \$\endgroup\$ Dec 15, 2020 at 19:21
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Your assumptions are flawed; re-examine your framing.

Depending what oscilloscope capabilities you need, you are unlikely to need to spend $200. And if you're willing to use LabVIEW instead, you likely don't have any specific needs.

Personally, I got a kit off amazon for about 20 bucks and built it in a couple hours (https://www.amazon.com/gp/product/B0195ZIURK/). It was easy to build, useful, small, and cheap. Also, I solder rarely enough that it was fun to do, though YMMV on that point.

The comments recommend buying a used scope off eBay or similar, which is likely also good advice.

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Not really as intended; NI sells a bunch of oscilloscope-rated cards and devices to use for that - but they start around $1200. Then LabVIEW has a set of drivers specifically used to emulate an oscilloscope called NI-SCOPE you can download for free; here's the README.

However you can use a DAQmx card as an oscilloscope with a variety of limitations, see Can DAQ devices be used as Oscilloscopes? for tips on how to do it as well as this NI forum thread for the LabVIEW part of it.

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  • \$\begingroup\$ Yeah and for $1200 you only get 50MS/s, which is on-par with the cheapest hobby-level scopes. 2GS/s cards start at ten times that price. \$\endgroup\$ Dec 16, 2020 at 9:12

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