Travaillons sans raisonner, c'est le seul moyen de rendre la vie supportable
An Arduino (Uno) shield for two stepper-motors, one Servo motor, and an alternative output. For the SphereBot, another Egg-Bot derivative.
This SphereBot is built with a retired Sparkfun Arduino Ethernet Pro board and the steppermotors from a 2009 Makerbot. Firmware and host sw (fork) from thunderbug1.
Download the Eagle schematics and board (ZIP 100kB).
I built the simple signal generator described in Electronic Design. The same circuit you find on ZL1NC and epanorama. Together with an Oscilloscope it can be used to find a cable fault as described in this All about Circuits article.
The 74AC14 SMD is mounted on the board its trace side. All other parts are through-hole. Most parts were salvaged from old electronics. You can adapt the PCB to your needs.
Now working on a small breakout board for the Nanotec microsteppercontroller. To be used in the RepRap 3D Printer.
For those interested, you can download the Eagle files (ZIP 291kB)
The parts-list you can find on Thingiverse.