Need help on how to use a variac.


I just bought a variac and will use it to bring back some old equipments. I need your advise on the following questions:
What is the starting voltage?
What are the incrementals?
How long I need to run for each voltage setting?
Thank you very much.
atranz
This is one I've found on the internet:

http://www.classamp.com/amprestoration.html

I have a few books at home dealing with this with guitar amps.

Hope this helps.
Rich
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