So because the DIY a pulse width modulation circuit really pays no longer: Here you can get for 11 EUR the overall circuit with screw, the potentiometer is screwed on an angle to the board, even a nice knob is. The module can be screwed through corresponding holes on print or in a housing (note cooling depending on the load!) Installed. The electronics are soldered 1A and works great, the operating voltage can be selected within a wide range, it can be controlled LED lamps, motors and much more. Here the price / performance ratio is 100%.