Just bought a DS203 from Amazon, now need help using it


I’m a Computer Engineering student, I’ve just recently started learning how to use o-scopes in my labs and know how to use the fancy more expensive ones, but I wanted something portable and can use at wee hours of the night when my lab room is not open, I decided to pick up this little gadget that everyone loves so much.

I have been able to do very basic things with it, like output a square wave from the function generator and have it run through my circuit. What I want to do now is analyze input and output signals, but when I tried doing this with just a square wave, but the waveform never stays steady in run mode. I’ve tried adjusting the frequency and time scale, but I can never get it to stay steady.

Please let me know if there are any videos or basic usage guides or examples of how to use this scope. I have tried searching google and they seem to be on hardware version 2.6, but my screen says hardware version 2.72. I’ve also attached the image that shows my boot up screen of the DSO.

Any and all help is greatly appreciated!!

There is not a huge difference in hardware versions 2.6 and 2.7 so anything you see on the s/w side for 2.6 will pretty much apply to yours. The one thing to be careful of is the amount of ‘disk’ storage on the hardware. Most models have 2MB, but others have 8MB. You can tell that by plugging in to PC and seeing what it reports. That does affect what alternative software you can load like the community app version instead of the supplied software as much of it assumes the 2MB model. It is fairly easy to play around with the software and you might also want to check out things like the Pawn scripting software as that allows you to use and write scripts for specific measurements, in effect turning the device into a specialised instrument.

On usage, it sounds like you need to play around with and understand the triggering in order to get a steady display. There are various triggering modes, Auto, Normal, Single etc., plus different settings for the trigger itself, edge, automatic, manual. Auto and normal are similar except that Auto will trigger after an interval even if it can’t find a real trigger, this can give an unsteady display if there is not a good trigger as it is effectively just starting at random intervals with respect to the signal. Normal will only refresh when it gets a real trigger so the display won’t update if there is no trigger. Single is what is says; it will only capture once after it finds a trigger and needs to be re-armed with the run button. Triggers settings are then selected by edge (+/-) or level, plus auto level or manual. Auto tries to find the level based on the input signal and can be set to be 1/4. 1/2. or 3/4 of the signal extremes. Manual allows you to manually set a trigger threshold which you can see as a horizontal line on the screen. Triggering will occur when the signal passes through this threshold.

Thank you!! I’ll give this a try later on and see if I can get the square wave to stay steady.


I also bought a DSO203, same version.

Is it normal to have a moving signal on CH B using the waveform generator (wave out)?
With CH A no problem.


Have you changed the trigger source over to B? It can be set to any of the 4 channels and needs to be on the one where there is the signal you wish to trigger from.

Hi bobtidey,

How do you mean?

Here is what I done:

  • plug a probe to Wave Out
  • plug a probe to CH B
  • made a contact between both probes

Then the selected waveform appears on screen. But the signal is moving.

Thank you

OK, sorry, I found the trigger stuff. It is a bit different with this version of hardware/software.

Have to press the “^” button to activate navigation in the right part of the screen.

Thank you very much for your help!


I bought DS203 in Amazon too. My problem: CH A/CH B doesn’t showed in main menu.
Anyone can help me?