Wolfgang Schmidt (3)

| Sure, you can easily buy an LED flashlight at the hardware store. But where's the fun in that? This DIY LED flashlight offers up to 78.8% ef...

| A step-up or boost converter circuit converts a low voltage into a higher value output voltage. With an input voltage in the range from 8 to...

| A simple NiCd charger can be built using ‘junk box’ components and an inexpensive LM317 or 78xx voltage regulator. Using a current limiter c...