Well, I picked up this: http://www.jeepbymail.com/ROBOT-ARM---CES---MICROBOT,i7537814382,c50924.htmlto play with. It looks fairly decent, but it came w/o any kind of docs, wiring diagrams, etc. Since it appears to already have a built-in control board for the stepper motors, I'd hate to start hacking it apart, but I'm kind of flying in the dark, here. There are two interface cables: a ~44pin ribbon cable running to a ISA-ish (not really ISA, I don't think, the contact pads are too big and far apart), and a two-wire cable ending in a mono-style headphone plug -- the big home-stereo kind. The jackplug is obviously the 12VDC power supply, but both wires are black. So, before I start throwing volts at this thing and reverse-engineering the interface the hard way, has anyone ever seen/used one of these before? At minimum, I'd *really* like to know the DC supply polarity in advance, so I don't smoke something. Otherwise, I guess I'm just going to have to take it apart and try to find a diode or some silkscreening on the interface board that'll tell me something.