If you have a common and three legs you can ignore one of the legs. Some
experimentation with an ohmmeter should eventually lead to figuring out
which is the common. 

A ULN2003 should be good enough to drive it. It won't be a powerful or
efficient setup, but who cares?

Make your oscillator adjustable frequency because chances are good there
will be some speeds that work better than others.

You can also use that extra leg for some feedback to your oscillator,
but it'll take some experimentation to find the best way to couple it
in.

Sometimes playing around with the motor driver can be as much fun as the
rest of the project :)

Cheerful regards,

Bob

On Fri, 28 Mar 2008 15:12:50 -0400 (EDT), piclist@ian.org said:
> On Fri, 28 Mar 2008, Bob Blick wrote:
> > Since you don't need the motor to start(spin it by hand to start) you
> > can do almost anything and it doesn't need to be three phase. I've done
> > it with a CD4049 as an oscillator, and two power transistors running out
> > of phase of each other driving two of the legs of the motor, and tie the
> > other motor leg to supply voltage. Give it a spin and away it goes.
> 
> I have been using a ULN2003 datlington driver package for running my
> LEDs,
> would that work for driving the motor?
> 
> Hmm.. the motors have four wires.  Three for each coil, one for common. 
> I 
> don't see how to tell which is common though, they are unmarked and have 
> the same reistance.
> 
> I'll poke around with one and see if I can get it to do more than twitch.

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