[sdiy] Re: No Variac Warning!

[eric b]

>I wouldn't advise using a Variac with anything using a transformer!!
>(Variac to transformer = Heap Bad Mojo)!
>Seriously folks
>The windings of many a transformer are simply not designed for
>anything other than a standard mains supply from the wall.

This is not correct. So long as the transformer is fed the proper
FREQUENCY, in a clean sine wave, it can be fed any AC voltage
from zero up to its rated input. Service technicians routinely
use variacs to power-up equipment slowly after repair--even
items with switching power supplies. And fixing old tube equipment
absolutely demands the use of a variac, to re-form electrolytics.




E. Barbour
metasonix