We’re used to those high voltage projects which use a self-oscillating transformer circuit with a TV flyback winding, and we have even at times railed against them for their inefficiency ...

Here you can see he’s using a solder gun to make the connection between the new battery and one of the solder tabs. He uses the gun instead of an iron because he needs to heat the joint quickly ...

Warrior offers a 12V Cordless Variable-Speed Rotary Tool Kit for $29.99. It has a five-mode variable speed control, which gives it a range of 5,000 to 32,000 RPM. The Warrior 12V Cordless Variable ...