DIY alarm – Printed Circuit Board. Part 2.
![PCB 3D model top](https://shadyelectronics.com/wp-content/uploads/2023/06/PCB-3D-model-top.jpg)
Welcome back to the second part of this series on building a DIY alarm system circuit. In the previous article, I explored the various components that make up this robust security solution, including the LTE module, USB-C charging circuit, SIM…