Comments on: Amazingly cheap dual channel scope

By: Mario Longest

Mario Longest — Tue, 20 Apr 2010 08:42:34 +0000

There’s certainly a great deal to understand about this. I consider you produced some great factors in Characteristics also.

By: prog

prog — Thu, 10 Sep 2009 21:42:17 +0000

@vladimir T
http://www.adafruit.com/index.php?main_page=product_info&cPath=16&products_id=46

By: vladimir T

vladimir T — Sun, 30 Aug 2009 15:52:00 +0000

how do i program the Atmel Tiny45 mircocontroller?

do i need a special programming jig for this?
where should i buy it?

By: Bryan

Bryan — Sun, 05 Oct 2008 01:01:22 +0000

It graphs voltage differences over time – It’s an o-scope. Whether it’s good enough for what you need is another story, but that doesn’t change the fact that it’s an o-scope…

I really want to build this…

By: nubie

nubie — Sat, 04 Oct 2008 00:34:57 +0000

@ orv, you are right, but I was looking for something more like a digital storage oscilloscope, many times you are on your own so you need to save the data to look over while you concentrate on driving the car.

@jd, that looks pretty cool.

By: JD

JD — Fri, 03 Oct 2008 18:09:15 +0000

Interesting… I just bought something a little more sophistaced (with LCD): http://www.dpcav.com/xcart/product.php?productid=16330&cat=0&page=1&featured for US$ 48

I don’t want this to look like advertising… please remove if not appropiate.

By: Orv

Orv — Fri, 03 Oct 2008 16:32:39 +0000

@nubie: Agree that this is useful for some applications, especially automotive ones. Just being able to see O2 sensor cycling is handy, and that only happens a few times per second.

That said, there’s no need to pay $3000 for a ‘scope. There are tons of old analog oscilloscopes out there for under $100.

By: nubie

nubie — Fri, 03 Oct 2008 16:04:36 +0000

@ all the haters

I am sorry to burst your snobby engineering bubble(s), but this IS a scope and it is useful.

Have you ever tried to diagnose a modern car? (some with up to 30 separate simple computers).

Just being able to log injector pulse-widths or check the crank signal shouldn’t cost $3000, but it does.

Think outside the box people. I know some of you at least must be interested in cars.

By: jacques

jacques — Fri, 03 Oct 2008 15:31:40 +0000

Hello, i am the designer, i agree with everybody that it is not a real scope,too slow (but 10bits!) i should have call this a VuMeter with graphic functions, or realtime data logger,
but please, look at the simplicity !
This was also to demonstrate how today in electronic project the parts count has been replaced by the “lines of code” count (quite big in this case).

ps: pic vs AVR ? hot news:microchip offer to buy Atmel !

many thanks to Hack a Day for publishing

By: O Mattos

O Mattos — Fri, 03 Oct 2008 14:37:53 +0000

charlie: Have a look at the Microchip PicKit2 – it already has the hardware required to make this, and full schematics and source code are available on the net, even for the windows app. As an added bonus, it can even program pics, but if you don’t need that functionality you can probably simplify the circuit diagram to <10 components.

Adding simple ranging to this should be pretty easy – just regulate the Vref+ and Vref- pins to “bound” the signal you want to measure.

As far as sample rate goes, I think PICs can sample at full resolution to near 100ksps, and triggering can be simulated in software on the PIC. (or even in software on the PC, if you can stream the sample data to the PC fast enough)

This is good enough for most people, since most digital circuits can be slowed down by a factor of say 100 for easy debugging with an o-scope like this. For high speed analogue circuits you might need something better though.

By: pokey

pokey — Fri, 03 Oct 2008 13:54:07 +0000

This is probably nice for analog experimentation. It would be even better if it had a simple function generator. The theory I learned in my EE analog courses didn’t click until I saw them in action in the associated labs with RLC networks and op-amps with a function generator and scope.

That being said, a “real” o-scope is more than just an ADC and sampler. It needs some sort of ranging and triggering otherwise you can’t truly visualize a periodic waveform. As a previous poster said, it’s just a data acquisition device.

By: eric

eric — Fri, 03 Oct 2008 11:43:50 +0000

mre: I don’t think I’m following your criteria for what makes an oscilloscope. I’ve got scopes that are likely older than you are that use tubes and are little more than frequency generators and amplifiers attached to a CRT. That is **the** minimum requirement for a scope. Your other criteria are for more professional and modern models but that does not necessarily exclude this idea as a scope.

By: stealthmonkey

stealthmonkey — Fri, 03 Oct 2008 09:13:51 +0000

Yep i totally agree with you…

Not everyone has the luck or money to have a scope at his workbench (like me)… And not everyone needs high sample rates for small projects… So this nice little thing made by [jaques] is just perfect… It should be obvious for everyone that you can’t get the performance of > 500€ products ;)

An another interesting point in this project is that it connects as a HID USB device – when i’ve first seen the project on the main page, i thought: Uhm, it reads ADC, sends the values to UART und then theres this little USB UART chip like in many other projects. But especially the fact that USB is actually done in the Tiny makes this nice project very interesting. To also put up some critical statemens, the software needs some work to be good…

By: samy

samy — Fri, 03 Oct 2008 07:30:16 +0000

This is interesting for education purposes. See the measure project at olpc :
http://wiki.laptop.org/go/Measure/Projects

I added a page on our olpc-france wiki.

http://olpc-france.org/wiki/index.php?title=Explorations#M.C3.A9trologie

Feel free to comment and update!

Samy

By: ...

... — Fri, 03 Oct 2008 04:35:20 +0000

I personally would call it a data acquisition card rather than a scope (you know what with the low bandwidth, no trigger, no display, decent resolution, etc) but either way its a useful little tool. Its not new, but its certainly useful if you are looking at up to moderately high speed events (up into low audio frequencies are probably possible, but I would try it over about a KHz due to sample rates probably about 5ksps for a single channel) and don’t want to use your sound card for whatever reason (ie, you need to look at dc signals). I would be a little wary of the form factor sticking out of a breadboard like that (not using a right angle header would solve that) but since most people don’t need to scope mhz (capital m) signals it would work well.