Breakthroughs, discoveries, and DIY tips sent every weekday. Terms of Service and Privacy Policy. A Variac looks like a sci-fi laboratory prop. For some reason, I ...

As a variable transformer, often referred to as a variac, it lets [Lajt] select how much voltage is passed through to the output side. There’s a school of thought that says slowly ramping up the ...

For his older variac, he decided to automate the device by adding a stepper and belt to turn the knob. The stepper is controlled by a Pololu stepper driver, which in turn get’s its marching ...

Visually, the light bulb colour goes from an orange glow to a bright white glow as the voltage is increased. Place the variac on a horizontal surface near a power outlet. Connect the light bulb to the ...

When a length of copper or nichrome is heated, it lengthens due to thermal expansion. The wire is suspended between two posts and heated by a variac. A small weighted hook is placed in the middle of ...