Use of Variac, Necesary?

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "manuel font by way of Terry Fritz <twftesla-at-qwest-dot-net>" <teslatechcr-at-yahoo-dot-com>

Hi all, this is the question:

Many coil builders hook up a variac at the
transformer's primary.  It is necesary?  May I
eliminate the variac?  I have an NST, 7Kv, 30mA.

Cheers,
Daniel 

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