The circuit controls unipolar stepping motor.
The generator (555) with decade range of frequency drives logic circuitry.
In real construction change value of the capacitor to set needed speed of stepper and replace bulbs by driver + winding.
IC's:
7474 - Dual D-type Flip-Flop - 1;
7400 - Quad 2-input NAND gates - 2;
7408 - Quad 2-input AND gates - 1;
ULN2003AN - stepper drivers - 1;
555 - timer -1.
