Rich Grise wrote:
Josepi wrote:

Careful. Variacs are known waveform distorters. The government would not
let us use them for precision power measurements as the waveform adopts
many harmonics in some units.

Where do you get this information? A variac is nothing but an adjustable
autotransformer - what part introduces the distortion?

Thanks,
Rich

And while youre at it you should tell him that the word
Variac is a registered trade mark. :-)
...lew...