I am trying to verify that a system can run at 50 or 60 Hz and 100 - 240 VAC. Can a Variac be used change both output frequency and voltage or just voltage? The typical solution to your problem would ...

The folks at TOG, Dublin Hackerspace, have a large variac. A variac is a useful device for testing some fault conditions with AC mains powered equipment, it allows an operator to dial in any AC output ...

It’s no surprise that many hardware hackers avoid working with AC, and frankly, we can’t blame them. The potential consequences of making a mistake when working with mains voltages are far greater ...

As the voltage is increased, the current increases which results in an increase in temperature of the filament. The increase in temperature affects the range of wavelengths emitted by the light bulb.