MOTs do make good L ballasts!

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

Original poster: "by way of Terry Fritz <teslalist-at-qwest-dot-net>" <Tesla729-at-cs-dot-com>

Hi all,

I just wanted to let everyone know of my little experience. I had been
having trouble getting my big x-ray transformer properly input ballasted
to run my big Jacob's ladder. I had been using a smaller x-ray tranny
with it's secondary shorted to ballast the big one but this was just
pulling too much current. The smaller ballast transformer was getting
so hot that the oil was smoking and stinking up the shop. Not to
mention that the outside of the twin seriesed 1156 Powerstats were
getting quite warm to the touch pretty fast. So I removed the smaller
(like ~200 lbs.) ballast x-ray tranny and tried a few other spare induc-
tors that I had lying around for ballasting. All of my other spare
transformers and variacs failed the test until I come across a couple
of spare beffy MOTs. I parelleled them together in series with the
input to the big x-ray tranny and of course shorted the outputs of the
MOTs and viola! it worked like a champ! I placed the new ballast into
a plastic bucket and submerged them in oil. Now I have very smooth
linear control of the current draw of the big x-ray tranny thoughout
the range of the twin Powerstat 1156 variacs when the Jacob's ladder
started firing -- usually around 50 on a 0 - 100 dial scale w/ 0 - 240 volts
output, so at about 120 volts in. Note that the minimum spacing of
the Jacob's ladder's rails is ~ 8" apart :^)

I had read that you need to design your Tesla coil's power transformer
ballasting so that you can smoothly control and fire a Jacob's ladder
before you hook it to your Tesla circuit and that MOTs w/ their secs.
shorted are some of the best ballasted that you can obtain (at least
for the price :^) It looks like who ever stated this knew what they were
talking about :^)

Sparkin' in Memphis,
David Rieben