In this case, they’re being used to create a basic PWM motor controller. The trick is to set the 555 up in astable mode, and use diodes and a potentiometer ... PWM motor control and the ...

This is an easy tutorial showing how you can control the brightness of an LED or adjust the speed of a DC fan using Arduino Board, a small BC547 transistor and a potentiometer. In my example the whole ...

The Arduino source ... 3D printer based around these ‘DC motor stepper motors’ which we will watch with interest. While we’re on the subject of closed-loop control of DC motors, here ...