When I built the first revision of Moteino I had to come up with a way to program and test them quickly without having to solder the headers. I saw how others built complicated jigs for this purpose with all kinds of features, so I wasn’t very excited to do something like that.
It needed to be quick and simple (without the ‘dirty’) and also without a lot of waste – spring loaded test probes (aka pogo pins) are expensive and when revisions change sometimes the positions/function of the holes change as well and I didn’t want to spend a lot of time/$ making a jig. So I just stacked two of the same PCBs as the target and used pogo pins to hold the PCBs together (or rather the PCBs to hold the pins aligned and leveled). That worked great, with one hand I could hold/press the target PCB on top of the pogo pins, with the other do the programming.
So what are ‘pogo pins’?
They are small cylinders with a piston tensioned by a spring that pushes it out and they come in all sorts of lengths, thicknesses and tip configurations (they actually have codes for each tip type and length), a picture is better than words:
Other PCBs required testing so I built quite a few such testing jigs, here are a few examples, notice the simplicity:
The rest of this blog entry is a guide to making jigs like these. Your final solution and it’s capabilities is only limited by your imagination. For instance you might test if a pin goes high by soldering an LED, or turn a pin HIGH/LOW by soldering a switch.
