> I got it.  Seems like a long way to go to avoid using an ohmmeter.

I actually agree. I advise people to go to RS and pick up a cheap unit.

> I was also not sure how much you can feel a shorted winding 
> on a stepper motor, since most have fairly strong detent 
> forces to begin with.  I didn't have a stepper motor handy to 
> try on, so I kept quiet.

On the ones I've tried, its is very noticeable. The current generated by the
rotation of the magnet through the winding is coupled back into the winding
in exactly the direction necessary to oppose that motion. It's called "Lenz
law" if I remember correctly... But you probably know more about the theory
of it than I do. The important point is that ALL the energy you put into
turning the shaft comes back to prevent you from turning the shaft with the
exception of that which is normally lost in any generator / motor system. So
the net effect is pretty strong.

>  Your method also has the problem of 
> not determining polarity easily.  If you've got 4 pairs, just 
> tying one from each together will only work for 2 out of the 
> 16 possible combinations.

Absolutely true. However, the polarity is easy to fix AFTER you get the
common wire sorted out and the phases connected in any polarity. If the
motor vibrates, you swap one A and one B phase wire. If it rotates in the
wrong direction, you swap the A wires.

> Then there's the question of why is someone messing with 
> stepper motors that knows so little about electronics that 
> they have a phobia for ohmmeters.  Or at least why would you 
> want to put yourself in the position to support them.
> It seems like a no-win situation.  When something doesn't 
> work they'll blame you.

They do blame me, but not as often as you might expect. So far, people have
been very understanding and have been willing... Ne... More interested in
learning rather than in blaming.

> It did make me think a little about how to automate this with 
> a PIC.  Plug in up to 8 wires from a stepper motor and a few 
> seconds later it tells you what's what.  Then I realized this 
> would be a low volume product and the same people that don't 
> want to spen $15 for an ohmmeter aren't going to spend $200 
> or more for a stepper motor tester when you can buy a new 
> stepper motor for $20.

Very true.

> I've also stopped responding to general requests for help 
> ever since I found out you were sensoring my posts behind my 
> back and despite your promise not to back in October.  I now 
> only jump into interesting intellectual discussions or when I 
> otherwise feel like it or have something to gain myself.  I 
> don't want to "support" the PIClist with free help as long as 
> my posts continue to be subjected to sensorship.


You are very welcome to your opinion and feelings on that subject. I have no
expectation for your to continue to participate. Do so or not as you wish.
My request was sent to the entire list, and even after my second request, I
did not have a specific expectation that you, Olin, would respond. 

I do appreciate your response here, thank you.

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