“This is my next build using LED matrix’s. You may have seen my last one - 81 LED Chaser, well this project uses 100 LED’s and is an oscilloscope!
Admittedly, the resolution isn’t great for checking measurements (it is only 100 pixels!). However, it is fantastic at visualizing audio waveforms via a mic.
There are 4 IC’s that make up the project. First there are the 4017 decade counter and a LM3914 LED driver which control the LED’s. Next is a 555 timer for clock input and lastly a 386 op amp to increase the signal.
If you want more technical detail of how it all works, then check out this link
I have used the 5mm X 5mm square LED’s again for the LED matrix and they work great in a project like this. If you have ever tried to solder a bunch of round LED’s into a PCB then you’ll know that it can be hard keeping them straight. The square ones have a flat top which makes it wash to align them correctly and keep them straight and flat.
This is a really fun little project and although it has a lot of LED’s, the overall components is minimal and isn’t hard to put together. Credit to Eddy Bergman who I was inspired by to build this project.”