If you’ve ever wanted to plot shapes using an oscilloscope, YouTuber Electronoobs reveals the tricks in his latest video. In it, he draws a Christmas tree, along with a few other designs, and while that holiday is now past, there’s always 2019. Of course, you don’t have to wait, as these concepts can be applied to anything you like throughout the year!

In the video, Electronoobs uses an Arduino Nano to produce PWM signals on two channels, filtering each of them with a capacitor and resistor. As he explains, shapes must be fairly simple, and end in the same place they started. Even with these restrictions, once the oscilloscope is turned to x/y plot mode and the signal is tuned in, the results are quite good.

In this tutorial we will use two pins from the Arduino to create fast PWM signals. With a small filter, we change the amplitude of that signal according to the width of the PWM pulse. By that, we can draw shapes on the oscilloscope when in XY mode.

Code for the project can be found in Electronoobs’ write-up here.