As great as theoretical explanations are, there’s a lot of value in watching the internals of a stepper motor move when its coils are activated in order. Also demonstrated are PWM-controlled ...

Modifying a stepper motor by drilling a hole down its shaft probably qualifies for the satisfying mod of the year award. That’s what [Russ] did to make needed improvements to his CNC flat-coil ...

F. R. HAIGH has recently compared the relative advantages of magneto and coil ignition used for generating the explosions which occur in motor-car engines (Students' Quart. J. Inst. Elec.