The first JeeNode circuit board was very exciting to make, back in January 2009:
Initially, I just wanted to get the connections right and didn’t care for silkscreen labelling, so there was none. It was created with CadSoft’s EAGLE, a commercial package with a freeware version for small boards. The “JeeNode” name came a month later, by the way.
The learning curve of the EAGLE package is steep, but then again, drawing this sort of stuff is going to be complicated whatever you do, because it’s not about drawing a nice picture where only aesthetics matter, but a meticulously designed diagram of which all the paths and connections have to follow certain rules, such as wires not crossing (doh!) and wires all having a minimum width and separation.
Here’s the JeeNode v6 PCB in comparison, of which many thousands have been produced:
It’s still surprisingly similar in design to the first iteration, although the production details and fabrication process have greatly improved over the years. One aesthetic detail I’ve always been pleased with is the blue-with-gold color choice. The gold plating is easier to solder than the HASL process I used initially, and is much more resistant to corrosion. Don’t think too much of this gold layer, by the way: it’s chemically deposited (fairly nasty stuff, from what I understand) and only a few atoms thick. Still… enough to do its work, and visually attractive (all in the eye of the beholder, evidently).
The purpose of a PCB is three-fold: a physically strong base for all the components, a reliable interconnect between all the pins to implement the actual circuit design, and silkscreen labelling to ease assembly and use afterwards.
The result: a tangible product. Quite an exciting change for a software developer used to work with bits and bytes, and who could never before point to the “real” result of it all!