DIY Oscilloscopes

[Guurf2]

So iv'e been looking around Ebay for an oscilloscope and i came across some small DIY/Pre-Assembled Arduino kits of some, prices around 15$-25$ or so.
did anybody have any experience with these? are they any good for the job for DIY pedals? do some of you guys use them or do you all use the big expensive ones?

would like to get some advice about these since i consider buying one and what makes me want the DIY small ones is a few reasons:
1. takes far less space in my room
2. cheaper
3. i like the DIY, i made a similar DIY transistor tester which worked great so i thought it might be as much fun.

Thanks,

Guy.

[BetterOffShred]

I personally do not have experience with any of these units, though I am looking to get the DS0138 model.  I have read a firsthand account on I love Fuzz forums from a member who has this unit and used it to test audio (read: guitar) circuits with success.   For 15$ I figure it's worth a shot for the level of need I actually have for an oscilloscope.   I think all three of your points are valid, and if you can swing the 15-25$ without leaving your wife and kids out in the cold with no food and clothing, then I say pull the trigger and then let me know what you think 

[ElectricDruid]

Depends how much you think you'll use it and how much space you've got.

These days you can pick up 2nd-hand basic dual trace analog scopes (say, 10-20MHz) for $50-$100. But they're fairly large, so no-one will ship them anywhere. That's one reason they're so cheap, because unless someone near you wants one, it won't sell at all. Try eBay or Craigslist or Freecycle or similar. If you want something for audio work, that's pretty much ideal, and you'll get more screen and more detail than you will on some tiny thing with dots.

But then that's the clue - "tiny thing". Nice to have something you could put in your pocket or can stuff in a drawer when you don't need it. That's *not* true of any cheap analog scope. Some of the modern digital ones manage it, but then you're into much more money.

HTH,
Tom

[potul]

I have one japanese kit that I bought already assembled

http://www.jyetech.com/Products/LcdScope/e062KC.php

It's ok but has some limitations.

But lately I use a usb scope I got from aliexpress for a cheap 40$ or so. It includes a logic analyser which is great for digital stuff troubleshooting. But it requires some tinkering with the software.

For the level of stuff I do they both are ok. But the usb one is much more powerful.

[MetalGuy]

It's just not worth the time and effort to build a DIY scope provided you can get a brand new one on ebay like this one for example:

https://www.ebay.com/itm/Hantek-6022BE-2-Channels-PC-Based-USB-Digital-Storage-Oscilloscope-48MSa-s-20MHz/192329643092?epid=19002951421&hash=item2cc7bd7454:g:2-YAAOSwq9NZ3GYo

You'll NEVER be able to build one like this for that kind of money not speaking about the software and  the probes that come with it.

[ElectricDruid]

Yeah, I hadn't thought of that, but a USB scope is a very good option - all the power and storage facilities of a desktop scope, but also fits in a drawer when you're not using it. Nice.

The only thing I would say is that when they stop updating the software, your scope is going to stop working. That doesn't happen with a "hardware" scope. That one already doesn't support the latest windows version. Sure, you can keep an old laptop around just for the scope, but at that point it's not as cheap or as small as it makes out.

Tom

[MetalGuy]

That one already doesn't support the latest windows version.

Many people wouldn't care as they are still using Win 7 (and not planning on updating to 10) but if you need alternative software and detailed info on that one check this thread:

http://www.eevblog.com/forum/testgear/hantek-6022be-20mhz-usb-dso/

You might also want to check this one as a better alternative still on a budget:

https://www.ebay.com/itm/OWON-VDS1022-USB-PC-Digital-Storage-Portable-Mini-Oscilloscope-25MHz-100MS/302320538379?epid=890490159&hash=item4663b5530b:g:WQoAAOSwySVZ9otP

http://www.eevblog.com/forum/testgear/owon-vds1022i-quick-teardown-(versus-the-hantek-6022be)/

[R.G.]

That's a great price, if it functions well. I have two Tektronix storage scopes with multiple plug-ins, enormous flexibility and 100MHz bandwidth that I have completely stopped using. Instead, I use a Picoscope 3000 series that I bought about 10 years ago. Cost about $250 then, but has been worth every penny.

The newer Picoscopes are still a couple of hundred dollars, but they include an arbitrary signal generator output channel, for a whole audio test setup in one box.

[Rob Strand]

IMHO, when it comes to debugging *any* oscilloscope is better than nothing.   The ability to debug stuff quickly is worth the $100 (or less).   

If you want to do this stuff often it *is* worth paying a little extra.    Perhaps even choose brands that proactively support their products with software update and support for old models.  I've noticed these are the characteristics of companies/people you can trust.  Generally the insides of their products are developed better as well.

I have two Tektronix storage scopes with multiple plug-ins, enormous flexibility and 100MHz bandwidth that I have completely stopped using. Instead, I use a Picoscope 3000 series that I bought about 10 years ago.

Interesting comment.    There's certainly a lot more flexibility in using the PC based stuff.  Some of the Tektronix stuff is getting outdated, like some need flashsticks (which must be < 2GB) and used dated PC to get the data off.   Nonetheless I've found the Tektronix to be very trustworthy.   

One company I worked for had Tektronix as we got more people we got some cheaper Rigols (which have many modern features).   The Rigols were for general use, which they were OK for.  However,   we also used the oscilloscopes for verification and testing.   In one of the test reports we noticed some weird numbers.    To cut a long story short, the test required us to zoom in closely on a waveform  and consequently the samples you couldn't see were off the screen and clipped.   We found that the Tektronix scopes would recover from overload in one sample whereas the Rigols would take a very long time (IIRC  in the order of 1ms).  The overloaded samples prior to the measurement point corrupted the following displayed points.   There were a few other instances of weird behaviour as well.

Finer details like like this is really where the companies who have been doing this stuff for a long time stay a notch above the others.  Like if you read the old Hewlett Packard journals the knowledge in the company was astounding.  Having said that  a lot of these companies are fraying.     The knowledge is evaporating and internally the focus of the company has moved sales (and politics  ).   

[Juan Wayne]

For what it's worth, the cheap USB DSO2090 I have has served me well for many years even on engineering-level jobs, has a lot of functions, does FFT, many kinds of operations, pretty much everything a high end desktop one does but with it's limitations from being on the cheap side. I'm a strong militant of the DIY, but an oscilloscope can be had for cheap with better soldering than I'll ever achieve is exactly what I needed and what I got, so I'm happy.

That said, I'll always envy those who get to work with a full sized, real life one. Hell, if I had the room and money to afford one (they're not cheap where I am and as ElectricDruid pointed out, they'll rape you with the shipping), I'd go as far as getting the old-school, green screen ones I worked with on my previous jobs. They might not take screen shots, but they're as precise as they get and they look cool as @#$%. It might sound weird and extremely nerdy, but you get a "feel" of the signal, which is awesome.

[EBK]

I taught circuits labs in grad school.  We had some pretty cool scopes available for our classes -- not necessarily state of the art, but nicely-featured digital scopes (I remember having to teach the perils of simply pressing the "Auto" button and expecting excellent results every time, but I digress.). 

So, what do I have in my toolbox?  Two dirt cheap scopes.  My favorite one is my Xprotolab Plain (http://www.gabotronics.com/oscilloscopes/xprotolab-plain.htm).  Why is it my favorite?  At $20, you can have a mixed signal scope with 2 analog channels, 8 digital inputs (logic analyzer and protocol sniffer), an arbitrary waveform generator, a spectrum analyzer, and more, AND it fits in an Altoids Smalls tin! (Uses my phone or laptop as its display through a USB cable) 

[Digital Larry]

I had an older Velleman USB scope for awhile.  The PC software was "OK" but I had a hard time wrapping my head around it as an old school scope user.

That device gave up the ghost (apparent HW failure) and ultimately I bought the 4-channel version of this:

https://www.amazon.com/Hantek-DSO5072P-Digital-Oscilloscope-Bandwidth/dp/B00RJPXB6Y?SubscriptionId=AKIAILSHYYTFIVPWUY6Q&tag=duckduckgo-d-20&linkCode=xm2&camp=2025&creative=165953&creativeASIN=B00RJPXB6Y

I don't like having to fiddle with small things that fall off the bench or connect things to my PC just to see where voltages are.  I think these things are a steal and it suits my needs pretty well.  Put it in measurement mode and you see about everything you need to know about the signal at a glance.  At > $200 I know it is outside of budget for a lot of people.  I look at these things from the perspective of how much time they will save me (a lot) and how much I value my spare time (a lot, increasing the less of it I have).

[Guurf2]

Thanks everyone!

[diydave]

For the few times I would use a scope, Xoscope on Ubuntu is more than enough. It's free, and doesn't take any space.
And with R.G.'s quick and dirty oscillator for a signal-generator, I'm good to go.



From time to time it pops up in my mind to buy and make one from Picaxe. http://www.picaxe.com/Hardware/Add-on-Modules/PCB-scope/
Seems pretty decent.