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The finger of God.

Original poster: "Christopher Boden by way of Terry Fritz <twftesla-at-qwest-dot-net>" <chrisboden-at-hotmail-dot-com>

After reading on the list that a "Choke" coil for a neon shop bombarder is 
the absolute greatest thing for an inductive ballast...I began scrounging.

3 phone calls, 2 short drives, and some basement digging later......

100lbs little cube. 8 position knob, nice little air cooled inductor, 2 
wires out the back with beefy lugs. Looks like it can handle a 10kVA pig 
with no worries.

So, of course, after sitting looking at this beautiful Pig sitting on it's 
cart for months now and not being about to use it, I had to play.

I cleaned off the new inductor (about 400 years of dust in there), and dug 
some 6AWG out of stock.....minutes later I had the pig set up with a 240VAC 
20A feed (I have a 40 and a 60 in the works).

At Notch-1 on the ballest I could pull consistant 8-12" arcs to the Jesus 
stick. The thick fire like arcs similar to a MOT. Cool So far, everything 
was exactly as I had expected. I can pull direct arcs up to notch 4 without 
tripping the breaker, therefore notch-4 is about 20A. :)

Did I mention the Group needs a decent ammeter? and a volt meter that reads 
higher than 150VAC would be nice too, lol especially when working with a 
variac that hits 350 for some unknown reason.

Ok....I proved the pig worked with the core and was happy.....then for some 
reason I actually thought I had a clue how these Tesla Coil things worked 
and attempted to hook it to Sam (6" coil).

(We now take a view at the actual thought process in Chris's head)

hmmmm ok...we're running 12/180 with 6 strings of the .1 caps, 9 caps per 
string......with the pig at notch 4 it draws 20A and the MMCs will trip a 
20A breaker in time......ok...if we use notch-4 and hook up the pig it 
should work.

<10 minutes later>

Chris: "Ok Ben....bring it up slow"
Ben: "Clear!........Fireing........ok that's 250 going in"
Chris: "um.......well....poo"

This went on for over 2 hours, with everything from notch 1 to 4, and up to 
10 strings of caps.

I can get it to tune, meaning at turn 3 it makes little, wus sparks about 5" 
long that I wouldn't be scared to put my tongue on they're so faint. 1 turn 
either way and nothing at all. The gap fires beautifully....just no output.

I was fully expecting to not have enough cap, cool, but I was at LEAST 
expecting, with 10 strings and the pig choked down to reasonable levels, to 
get a nice 6 or 7 footer for the demo today.

Well, after working for another half hour I managed to get back to where I 
started from. But at least it's stable, reliable, and (to a non coiler) very 
impressive, to me, 48" arcs are pathetic.

WHAT AM I DOING WRONG? I've thought over every aspect of this thing today 
and it's driving me nuts. I'm not touching it until after the demo today 
(because if I do I KNOW I'll screw it up, and do it 2 minutes before the 
class arrives, lol).

ok...so I set the pig aside, had the coil back up and running beautifully. 
The new panel is ugly, but works well enough to kludge through it's first 
demo......but there's the nice new inductor just sitting....hmmmm


off to the warehouse....bring the tranny back (ran it over the scale on the 
way back, 350lbs with pallet), hooked it all up, set the leads on the floor.

Slowly brought the power up......

It starts with the usual hum in the variac

then the corona hiss that even a little obit makes

then it starts to scream...it's like a high pitched whine of a turbojet 
spooling up.....like a powerline on a humid day.

Having just swept the floor we had spread a fine layer of dust on it. The 
leads were 3 FEET APART and there were arcs going acros the concrete floor 
about 6" out trying to connect :) (they actually were connecting, just using 
the concrete as a conductor).

ok ok ok ...we have to seperate them from the floor.....

I hung them in the air, from large twine, and tied a piece of string around 
one cable, looped around a metal pole, and back to me. In the odd event that 
a discharge came up the string it would (theoreticly) ground out to the pole 
before it hit me.

yeah, I know it's dumb, but you hold a string tied to a 150000 volt 
wire...it's the little things that make you feel better.

I brought the tranny up to 250VAC in and teh scream was loud enough you had 
to raise your voice to talk over it..this is WITHOUT any visible discharge!

then I brought them s l o o w l y together, fully expecting a wimpy 
(remember 16 milliamp output current) wispy little arc.....maybe as good as 
an OBIT.

At about 8" apart I could barely see corona, so I turned off the lights and 
started over...so that I could see this little whimp arc.

At about 7.5" or so apart....it happened

It's a good thing I had gone to the bathroom just minutes before.

Imagine the sound of a single static spark gap opened to 7".

The arc was WHITE HOT, about 7" long, and over 1" thick! DEAFENINGLY loud, 
and lit up the whole room VERY brightly (brighter than full sun).

This thing scares me, the Pig I have a VERY healthy respect for, the X-ray 
trannies I abolutely fear. I can't wait to play with it. :)

Have fun! It's time to to do FIRST PUBLIC DEMO AT SIGMA-6 TODAY!!!!! :)


Christopher A. Boden Geek#1
President / C.E.O. / Alpha Geek
The Geek Group
Because the Geek shall inherit the Earth!