smaerd
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Mood: hmm...
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Oscilloscope on a Chip
I find this absolutely amazing. Granted, this is not a perfect solution but for the price, it's well with-in the range of an amateur experimenter.
Personally I think this could represent a mile-stone in hobby electronics bringing home-made DIY apparatii dreams closer to a reality.
<$100(USD) oscilloscope bread board ready circuits are now available.
Article I read this from -
http://www.jameco.com/Jameco/workshop/ProductNews/smallest-o...
Some purchasing links(not pitching it but there are a variety of options to choose from)
http://www.jameco.com/webapp/wcs/stores/servlet/ProductDispl...
http://www.jameco.com/webapp/wcs/stores/servlet/ProductDispl...
"plain board"
http://www.jameco.com/webapp/wcs/stores/servlet/ProductDispl...
(most impressive cost-wise to me)
I'm wondering how difficult it would be to use a microcontroller(rPi or Beagle bone black) to drive one of these things and get some nice displays on
a computer. Something tells me writing a little soft-ware to handle the serial communication of the plain board would not be difficult, a tiny case
and well, could very well have a 30-40$ oscilloscope for general purposes...
Edit -
Oh wow... The data-sheet shows it already has this capability and the soft-ware/interfacing does not look difficult. Think they just earned 25$ from
me.
Edit again - Wow... Oscilloscope watch! Not the best scope but uhm, totally crazy hahaha. http://www.gabotronics.com/oscilloscopes/oscilloscope-watch....
[Edited on 2-6-2014 by smaerd]
[Edited on 3-6-2014 by smaerd]
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Artemus Gordon
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That's a cute toy (scope wristwatch) but when the probes are on a circuit you are effectively tying one arm down. Doesn't seem too practical, not to
mention the fact that I don't think you could learn much about a waveform by squinting at that tiny low-res screen.
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smaerd
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Yea the watch is more of a novelty I think. Or maybe the idea is actually just so you always have an 'scope at hand? Maybe it's for James Bond esque
stuff, like plugging your watch into something then pulsing in a stored wave-form. Not really, I just don't understand it's purpose/functionality. Not
sure. I like the USB functionality. Thinking about whether or not I could get it to work on my raspberry pi 'hack-top' so I have a portable
oscilloscope attached to my laptop. Checking out some of the features of the device, I'm pretty impressed by it. Forget the screen honestly, USB seems
the way to go(for me). Apparently the frequency can be increased drastically with a few small components, 256 samples isn't ideal but supposedly this
can be improved on without too much effort either? Haven't looked into that claim yet.
Soft-ware is also supposedly multiplatform and stable? Not sure but it is on Github so if there's enough open source people using it well, it will
eventually be stable. Also, if you get sick of it as a scope, it can serve as a project board. So I mean, to me the plain board is impressive by cost
and functionality. I am wondering why they do not have enclosures for all of their models though, that is a bit of a bother.
[Edited on 3-6-2014 by smaerd]
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Varmint
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For the price, its a nice introduction, and the clever experimenter could leverage it's capabilities to do some meaningful development.
But the bottom line is, an analog input (standard on many microcontrollers these days) does not an oscilloscope make.
The biggest problem is sampling rate. If the feature (or anomaly) you are looking for is an appreciable ratio of the sampling rate, you stand a very
significant chance of missing it entirely, or at least underestimating its repetition rate and overall influence of the circuit under test.
Many anomalies are a very small glitch or burst, with improper over-sampling you might be mislead into thinking a burst is at frequency "x", when in
fact it could be at 4, 8, 16, or 21.1237x the sampling frequency and completely misinterpreted by the digitizer.
Decades ago I developed a color capable NTSC digitizer to record (then) "high resolution lossless" video. It turns out in order to preserve
"lossless" NTSC video (standard definition TV in the US) required 27+MHz, and current thinking at the time indicated 2.1 times sampling rate would
achieve that goal.
That means 56.7MHz sampling rate "should" be "perfect". While 2.1x provided a very nice picture, the discerning eye could still tell the difference
between 2.1x and 10x. In fact you could still tell the difference between "live" and oversampling at 10.1x.
So, what does this mean? I wouldn't trust the output unless the sampling rate was at least 10.1X, and even then I would be fully aware that there
could be transitions well beyond the sampling rate that the digitizer missed completely.
Digital is the answer to many questions, just not all of them.
DAS
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gregxy
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These kind of scopes have been available for a while, although these new ones are smaller (which is not an advantage that I can see). I bought a
"pocket scope" on Ebay that works quite well, the analog sampling rate is 70Mhz. (so it is useful for sighnals of up to about 5Mhz) It has 2 analog
channels plus 2 digital channels. It was about $180.
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Texium
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Thread Moved
21-11-2023 at 14:00 |
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