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48x24 TrueColor Matrix by Pedro (Vocational School CIOR)

Who am I?

Hello, my name is Pedro Veloso, I live in Portugal and I am a teacher in the course of Electronics, Automation and Control Technician. I teach the subject of Automation at the Vocational School CIOR (Escola Profissional CIOR).


Why to build the TrueColor Matrix?

Our school aims to, among many other things, contribute to the integral formation of young people, providing them with adequate preparation for the exercise of a qualified profession and building a life project. We also provide students with a solid general, scientific, technical and technological training that enables them to be prepared to integrate into the labor market as well as to go on with further studies.

Over each cycle of training our students develop several "minor" projects appropriated to their level of training and each with very specific goals.

This way, when I found this website, I thought that the construction of the TrueColor Matrix would be a very interesting and comprehensive challenge to increase their level of knowledge.

Of course, the flexibility of the matrix, the perfect hardware solution, the excellent control software (Glediator) and its beautiful effects had their influence in the decision.

So, I proposed the project to two classes (31 students in total) who accepted it immediately with a great enthusiasm. Who wouldn’t?



The fact that the matrix is expandable in increments of 16x8 led me to think about doing a 48x24 matrix, i.e., 9 times 16x8.

This previous fact has determined the LED pitch also. I´m using a 20mm LED spacing.

At the moment I don´t know if I will let the pixels visible or diffused with acrylic. So, before I regret, I have decided to paint the foam board in matte black.

René and Thomas developed the matrix controller board with the possibility to choose between two LED currents, 70mA or 20mA, selectable by the jumpers. I’ve discarded the 20mA possibility and, instead of using 2k resistors, I use 1k resistors. This came out in one of the conversations we had. René told me that the light intensity between 70mA and 40mA is not much, but I want the maximum light possible.




  • Circuit Boards: All Done;
  • Aluminum profile frame: Done;
  • 1152 LEDs placed on the foam board: All Done
  • Columns and rows connections (4608 solder points): All Done;
  • Circuit Boards and Power Supply placed in place: All Done;
  • Circuit Boards power connections: All Done;
  • Circuit Boards to LED Matrix connections (504 solder points): All Done;
  • Testings: All Done and worked at first attempt;
  • Black 5mm Acrylic panels for enclosure: All Done. Black pannels would be a nice encloruse for the matrix but the work inside worth to be seen. So we decided to buy Crystal Acrylic;
  • Working time: 127 Hours.

Note: The first test made to the full matrix has revealed some leaking LEDs, causing some columns to lit. I had to replace 48 of them. I believe that some were defective but the mechanical stress applied to them was the main cause to kill them. So, be careful and read these notes.

Youtube video to come...

I can’t conclude without leaving a word of appreciation and gratitude to the hosts, René and Thomas, by the excellent projects that they develop and, above all, by sharing them.


Best wishes for all,




Controller Board Assembly

Matrix Construction

Youtube Clip