Instructables
Picture of Oscilloscope How To
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This tutorial will guide you through the basics of using an oscilloscope, it is meant for someone with very little or no experience with electronics or oscilloscopes.  There are many types of oscilloscopes out there, and each is a little different, so I'm going to focus on the essential components that are found in all oscilloscopes and are the most useful when getting started.

Oscilloscopes are useful for looking at very fast changes in voltage over time, things that we could not measure with a multimeter.  Usually when you make a measurement with an oscilloscope, you will see a line that stretches from one side of the screen to the other; this line is actually a graph of voltage vs time (fig 2), where voltage is measured along the y axis and time along the x.

Oscilloscopes come in two varieties: analog and digital(I'll be using a digital scope in this tutorial).  The controls on both types are basically the same; be aware that the digital scopes may hide some of there controls in a menu on the LCD display instead of using knob or button.
 
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Step 1: Controls Overview

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All oscilloscopes have some basic controls in common, be sure you can identify these controls on your oscilloscope:

- at least one input where an oscilloscope probe (also called a coaxial cable) can be attached (be sure you have one of these cables)
- screen with a grid overlay- this grid is useful when you want to make measurements using the scope
- volts/div- this control lets you change how many volts are represented by each vertical increment of grid overlay on the screen.  Basically, it allows you to zoom in and out along the y axis.
- time/div- this control lets you change how much time is represented by each horizontal increment of the grid overlay on the screen.  It allows you to zoom in and out along the x axis.
- vertical position/offset- lets you move up and down in the y direction
- horizontal position/offset- move left and right
- trigger level- this is a tool that allows you to stabilize your waveform on the screen, I'll get into the details later on in this tutorial

See the images above for examples.
Very good tutorial, in deed!!!!

Thank You!

very wellcome, next step: http://www.instructables.com/id/Girino-Fast-Arduino-Oscilloscope/?lang=es, but great tutorial once again!!!!

mikexeno2 months ago

Thank you for taking the time to write this up and post it for others to learn

sanjay11710 months ago
wow this is a great tut! here in india still oscilloscope is a costly instrument!
i bought one in chor bazar for 700/- inrs a redicullously cheap price!but i had to buy test prod for 600/- inrs. as i started using scope within few months i got payback and now i have four channel digital one ! thanks for this great help!!!
gizmaniac1 year ago
Amanda, Great tutorial. There are a couple things I'd like to point out to you that probably won't affect the casual consumer, but should still be noted nonetheless. The signal generated by the Arduino sketch will be ever so slightly less than 500hz, and also probably won't be a perfect square wave. It's close, but not exact. Firstly, the delay function is known to be inaccurate. To be spot on the sketch ought to use interrupts to toggle the voltage on the pin. Secondly, the code should use a state variable that toggles each iteration through the loop, and set the pin to that value each time through, rather that explicitly setting high and low. The number of TOTAL instructions to set either high or low should be identical. This is to avoid any minor timing variance introduced by the overhead of calling the loop function each time, which will only happen before the first of the two digitalWrite calls, thus producing a slightly less than square wave -- i.e. the signal will be low slightly longer for however long it takes to exit the loop function and re-enter it again. In practice this is probably only a few clock cycles, but it is still a real consideration, and over enough time will cumulatively cause a signal expected to be at 500Hz to eventually slip out of sync. Overall, it would be better to use a timer interrupt to generate the wave. These are HIGHLY accurate. I use them all the time for both audio and video sync with AVR chips. If you'd like a more thorough code example of how to do this I'd be happy to provide one. Example: volatile bool bState = true; const int iPinOut = 7; // arbitrary choice void InterruptHandler { digitalWrite(iPinOut, bState); bState = !bState; } Or something like that... (obviously I didn't provide the interrupt initialization.) Hopefully this makes what I am saying clearer.
amandaghassaei (author)  gizmaniac11 months ago
thanks for that info!
gizmaniac1 year ago
Minor correction to my last comment. The wave is still square, as the voltage change is still (more or less) immediate. What's affected is the resultant frequency and duty cycle. Sorry for the misstatement.
Tbus1 year ago
I like this free oscilloscope tutorial. I bought one from www.ciebookstore.com but I like the digital coverage in this one! Thanks.
What about mentioning the easyest signal-source for testing? About every Scope offers a Test-Signal, in the Pictures you see it next to the USB port...
FtForger1 year ago
Another suggestion for those wanting an oscilloscope. Once you've read up on them via things like this instructable, you should haunt a few ham radio swapfests. They can be found under the "Hamfest" link on the ARRL web site. You can find scopes that are perfectly usable for under $50 (I bought one for $25 in August). While there you may also find a lot of discrete components, and other items that you can scavenge parts from.
I'm glad you've written an introduction to oscilloscopes, they have always been a mystery to me and your instructions are very clear! I can't wait to put your instructable into action! I have a question though, could you recommend an oscilloscope to buy which will do all the functions you describe and doesn't cost the earth?
I would go for the Rigol DS1052E if you want a good cheap scope, I got one a few months ago and so far its turned out to be an amazing scope for the price.
Excellent! Thank you!
I have a Voltcraft DSO-3062C and it works really good. It did cost 299euro which in not very cheap but very good value for money.
amandaghassaei (author)  bricabracwizard2 years ago
thanks for the comment! Unfortunately I'm not really that familiar with the oscilloscope market, but yes they tend to be pretty expensive. I imagine that you could find a used analog scope at a university/goodwill/freecycle since a lot of people are switching over to digital scopes. Definitely look for something with two channels (dual channel), other than that, everything I mentioned in this tutorial is pretty standard.
sb372 years ago
I also found this:

http://www.instructables.com/id/DPScope-Build-Your-Own-USBPC-Based-Oscilloscope/
tkjtkj sb372 years ago
i got one .. assembly was very straight-forward ..
and it works fine ..

attaches to pc via USB .. it's software runs fine, too, on this XP Pro lappie ... I'd recommend it to anyone who can handle a small solderiron..

GMugno2 years ago
Try Jameco Electronics, they have a range of entry level to intermediate lavel scopes. There's a hend-held one on their home page right now for just $189 and they have USB ones too. You don't say what your needs are though?
These cheap ones are pretty limited in their frequency range.
GMugno GMugno2 years ago
*level*
sb372 years ago
Nice introduction to oscilloscopes. As for buying one, I wanted to add that probably the least expensive method would be to get a USB adapter that can help you get the oscilloscope display onto a PC. Something like this one:

http://www.virtualvillage.com/pc-based-oscilloscope-2-channel-digital-storage-001482-009.html?utm_source=googlebase&utm_medium=shcomp&utm_campaign=google_shopping_feed

I haven't used one myself yet but know of others who have used such a device for amateur projects.