This circuit is principally aimed at those wanting to control the speed on a mini drill, as often used for making PCBs however, the circuit could be used in numerous other applications where speed control is required in dc motors, or even model trains or remote controlled model cars/boats, for example (with suitable modification).

The circuit is designed to provide a typical output of 12V with a maximum power output of 100W. It also features short-term overload protection and an optional foot pedal control.

Items NOT included in the kit, but available separately, are:
Mains Transformer, 15V/150VA.
Bridge Rectifier, DOD24H.
1/4" Stereo Jack (for remote foot-pedal control), PLJ674.

Star Rating: ***

Ratings Guide.
*: Basic Starter Kit, little or no soldering.
**: Some basic knowledge of electronics required.
***: Detailed construction. Previous experience recommended.
****: Complex construction. Some test equipment may be required.
*****: Advanced, complex assembly and some test equipment may be required