I am currently putting the finishing touches on another printed circuit board.
Layout of a printed circuit board, or PCB, is one of the most complex puzzles I know. Creating a complex PCB takes a great deal of knowledge, a lot of patience, and a robust set of puzzle solving skills. These are the same sort of puzzle skills that might be used to solve a Sudoku or a tough crossword puzzle. Seeing patterns, spotting errors, trial and error, planning ahead, all skills used to their utmost in laying out a PCB.
A PCB is laid out with specialized software, drawn on the computer screen. The software can then generate CAM files that are sent to a board house, a manufacturer who can take these files and create a physical PCB. The PCB is thin layers of copper etched to create the patterns of traces laminated onto a fiberglass substrate. When designing the PCB each component, each copper conductor, each trace, is carefully positioned by the designer on the screen, dragging objects colored lines about to create a solution.