ballasts and such...

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

Original poster: "acmnovak by way of Terry Fritz <twftesla-at-uswest-dot-net>" <acmnovak-at-email.msn-dot-com>

Hi All,

On my next coil, I'll be using 2 NSTs with shunts completely removed. This,
however, will require utilization of external ballasting to control current
draw. I'd like to be able to use all the current provided by a standard
(120v 20a) outlet, without pushing my luck. This leads me to a current of
18A.
I was reading Richie's TC page a few days ago and drooled at his ballast.
However, he spent WAY too much on it. I'm a bit of a "budget  oriented"
coiler, so I've been looking for other, less costly alternatives.
Seeing as MOTs work well for some people, I first investigated the use of
those. I've got mixed feelings about them however. Some say they work
excellent and are the best thing, while others say they are cheap, saturate
easily, wimpy, lossy, and do not last long. I would think they should work
just fine, within limits. I'd like to hear (only the experienced') opinion
on this matter, as I really don't have any clear facts put togather on this
subject.
The next thing I pondered using, was a homebrew ballast. I noticed that
Richie's ballast looks strikingly like a NST with only the primary. I have
an old NST core sitting in the corner of my room that I want to get rid (or
make use) of, so I though " why not just slap a couple of turns on it and
it's almost exactly like Richie's...". So, I contacted Richie and asked him
how one might go about constructing a ballast in this manner. However, he
informed me that he had bought the unit from a manufacterer, specially
designed for his specs. This proved quite discouraging, as I would have to
do the math myself : ) Do any of you have the equations, and whatnot
required to produce a viable ballast? My core measures 4"X8"X2"and is in the
form  of a dual "E" shape. I can make accomodating brackets to allow for
adjustment of inductance by means of gapping if needed.
Just yesterday, I found a (suitable?) ballast sitting right there in the
bottom of my closet?! This really takes the cake on weird shtuff I find in
odd places... The thing measures5"X5"X1" and is wound with approx. 15 turns
of #6 square wire(!!!) and it's gap is set to about 100 mils (.1")  The
whole thing is coated in glyptol and bolted togather like it's made to take
some abuse. And, of course, It has NO markings which might help me
deetermine the usefullness of the device in question. How would one
determine if it will be suitable for my needs?
Any help would be greatly appreciated, as I'm quite new to this area of
coiling...
Thanks

-Michael
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