Stepper motors have found their way into Elektor Electronics many times, most recently in the November and December 2003 issues. In contrast to previous articles, we’ll keep it practical and won’t go into the theory. If you want to know more about the background, have a look at some previous articles (listed in the reference section at the end of this article).To get an unknown motor to work you really need to do two things: find out what properties your motor has and choose the right driver electronics. With the help of this article you will find that it’s not that difficult. The following three steps will help you discover the most important properties of a motor. The first step helps you determine whether you have a bipolar or unipolar motor.