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ohazi

Oscilloscope Specifications:

Maximum Sampling rate: 4MSPS

Analog Bandwidth: ---> 200kHz <---

Arbitrary Waveform Generator Specifications

Maximum conversion rate: 1MSPS

Analog Bandwidth: ---> 50kHz <---

This is certainly not the first project in the "super miniaturized hardware tools" category, and as much as I like the idea of having a single tricorder-like device that can replace a lab full of hardware, all of the similar projects that I've seen have fallen short in exactly the same way: analog bandwidth - the one spec that actually matters.

I would pay a lot of money for a miniaturized tool that took RF performance seriously.

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I would pay a lot of money for a miniaturized tool that took RF performance seriously.

I'm sure, but how many others would, vs just using bulky equipment? I agree the analog bandwidth is quite limited here, but it's good enough for audio work, and there's a large potential market there among live sound engineers.

Your output might be 20 kHz audio, but in the real world you're surrounded by analog at much higher frequencies. I've worked on enough "low bandwidth" audio projects plagued by problems at higher frequencies that I can't really recommend the "Its good enough for audio" approach anymore. You can easily have a tiny DSP with a noisy clock signal in the tens of MHz. Or a wonky USB signal. Or an intermodulation product from some unrelated circuit.

If I can pay $100 for a super miniaturized audio only scope, or the same price for a bulkier 100 MHz scope, I'd go with the 100 MHz scope every time, so in that sense you're right.

That being said, it sure is nice that today's scopes are more like a lunchbox than a boat anchor. My lab at work easily has a million dollars worth of "full size" test and measurement equipment from Agilent and Tektronix, but there's no reason the entire budget has to go to them. We're happy to pay for stuff like this (http://www.triarchytech.com/) when it's a solid product that makes our lives easier.

I'm thinking strictly of things like mixers and junction boxes. I take your point about DSPs and other system clocks (and am trying to figure out if this is an issue on a hybrid DSP/FPGA/discrete device right now), but in areas like live sound engineering your main enemies are things like ground loops, crosstalk between mixer channels and whatnot. These are installation issues rather than product development ones.

Seems like a portable, precision FFT analyzer would be more useful. The ability to measure frequency response, harmonics, cancellation, distortion, noise, etc. make an engineer's job so much easier. Frequency information is far more important than timing information.

What benefit does an oscilloscope have over meter+ears when resolving ground loop or crosstalk issues? Time domain information doesn't seem terribly useful.

Knowing whether a hum is 60Hz or not tells you whether it's a ground loop or some other problem. For crosstalk a lot of mixers have a 1khz sine tone generator. It's useful to be able to verify that you're dealing with a particular frequency. You are not always able to rely on your ears to the extent that you'd like when you're in the field, since the environment where a PA is being set up can be noisy as well.

This device has a few other tricks up its sleeve as well as a basic 'scope; it also does FFT, phase metering, and operates as a voltmeter. I'm not suggesting it's the ultimate device of its kind, just pointing out that there is a class of people for whom having this functionality in a highly portable package would in fact be handy.

Oh, and the protocol sniffer means you can test MIDI output from a synth or sequencer.

I don't know much about the work of sound engineers, but I'm curious, can you please describe some of the applications this device would offer to sound engineers?

I am not a professional by any means, but I use an oscilloscope frequently when building guitar effects pedals. Being able to see a fuzz pedal's "clip" is extremely useful.

Phase metering is quite important as quite a lot of audio gear can sum stereo signals to mono, which can lead to undesirable frequency cancellation and loss of signal. FFT is handy for all sorts of things, eg a high-frequency spike might indicate a blown cap in a filtering circuit.

I would not suggest that this watch replaces a proper oscilloscope for lab work. For that matter, the great majority of problems are more easily diagnosed with a computer and some decent audio editing software, which will have things like frequency plotting and phase metering built in. But it looks very handy for location work, eg there have been times when I've had to repair a cracked solder joint in a shotgun microphone in the middle of nowhere, and had no way of testing the gear I was working on before putting it back into service.

The one thing that I don't see on it that would be enormously useful (but also power hungry) is a backlight. It seems like you would end up needing to point a flashlight at it in many situations.

I'm a musician with a room full of synthesizers. This Oscilloscope is perfect for my needs.

Sometimes, you just have to stand back and think: am I criticizing this because I'm me and have a position, or because its really an issue for the wider dynamics of the target market? Fact is, a lot of nerds are going to enjoy rockin' an Oscilloscope watch - it may well just be a faddish toy - but some of us will use the hell out of the thing.

(I already have a few similar-spec'ed Oscilloscopes in the modular system. Having one on my watch is going to make it very fun to wire myself up and watch a few LFO's from afar ..)

We should talk...

About synthesizers and oscilloscopes? Sure thing! Whats up? :)

It's my thing...drop me an email, it's in my profile. If you're in the Bay area we should meet up.

I'm in Europe, but thanks for the invitation .. always nice to meet a fellow enthusiast.

Anyway, I'm a backer of this Oscilloscope watch now, I can't wait to wear it, and I'll definitely be wiring up my LFO's to the thing so that I can watch 'em while playing keys away from the modular interface. ;)

What analogue bandwidth do you want? Does the device need to have a display, or is a USB device ok?

I actually prefer the USB scopes. I paid a lot for a high resolution laptop display, and I'm going to have that with me anyway.

At work, I'm generally okay with a 400-500 MHz bandwidth for some of the more fiddly stuff. At home, 100 MHz is usually plenty, although I've occasionally had to take parts of my projects to the lab.

I'll concede that many hobbyists don't really need all of this capability (e.g. the Arduino + LED crowd), but I'd have a really hard time recommending a scope that doesn't do at least 100 MHz simply because you can already get 100 MHz hardware for dirt cheap.

It's gotten significantly easier for hobbyists to play with relatively high-end hardware that would have been out of reach a decade ago (FPGAs, fast memory, wired/wireless communication ICs, cameras, etc). A lot of this hardware requires relatively high bandwidth interconnects to work well (or to work at all), but today's hobbyists seem undeterred and are figuring out how to make it work.

But when the shit hits the fan, you don't want to be banging your head against the wall because of crappy test hardware.

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