2012-01-07 Printer mystery solved, blinkie work done

This afternoon I discovered why my 2nd 3D printer hasn't worked for the last week or so. It just refused to work one morning. It seemed to be associated with the power supply, whenever I attached it, I'd start getting garbage on the communications line.

Turns out I had a bad solder joint on the ground reference pin for the 5V regulator, so when the power supply was attached it tried to push 12v into the 5V line.

Upshot was that I blew one Pololu motor driver. I'm kind of amazed that the damage was limited to that. I'd have expected to have blown all 4 drivers, the FTDI chip and the CPU.

I now have one too few non-blown motor drivers to build that spherebot this weekend, so I guess that's pushed off to a later date.

I did get the Duckon blinkie PCB design finalized pending artwork approval. A sneak peek is posted just below.

I also took apart the brakes on the right side of the van (ran out of daylight to do the other side) trying to figure out why the hand brake doesn't really work. I still don't know. They were a bit stuck but even after freeing the lever and the adjuster they still don't do squat.