September 4, 2020

Drum Machine Part III - PCB Design

Now that I’m on the 3rd PCB layout iteration, the Drum Machine circuit is nearly ready for printing. My original design was intended for matrix boards. However, some wisdom and insight made me realize this was not a good idea. There are many aspects of PCB design I didn’t understand prior to this project. First off, PCBs are cheap. Real cheap. Under $20 for an order of ten 2-sided boards. No need to keep all the traces on one side nor waste time and effort soldering wires to a perf board. Another tip; Avoid 90-degree turns. Instead, implement wire traces with 45-degree angles to reduce noise. Give yourself one component-width between each component for easy soldering. Again, the slightly larger board won’t break the bank. I’m using 1206 resistors with 1.6mm wide solder pads and a 1.6mm wide screwdriver-style soldering tip. You should match the size of your solder tip roughly with the size of your solder area. 1206 SMD resistors are also a nice size to start with if you are just learning how to solder SMD components.