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Sparks (finally)

Well after about 9 months of scrounging parts, pondering, building,
pondering some more, scrounging some more, and more building I'm finally
getting some arcs and sparks.  Of course I was forced to put everything
aside for about four months with a temporary duty assignment to Egypt
plus the holidays and all.

Anyways, I was getting bogged down working out the details and scrounging
parts for a variable inductor to use as ballast for a few PTs and when I 
got up Saturday I decided I wanted to see some sparks so I hooked up a 
9000V x .030A neon to it and had a little fun.

The secondary is about 940 turns of #22 on a 6 1/4" HDPE tube and loaded
with a 20" x 5" toroid made of corrugated drain tubing covered with 
aluminum tape.  Primary is 15 turns of 3/8" copper tubing wound with 3/8"
spacing into a 15 degree inverted cone.  Inner turn is about 9".  The rest 
of the tank is two .060 poly rolled caps wired in series and two cylinder
static spark gaps with six .030 gaps in each.  All this is bussed together
with 3/8" copper.

I hooked up the 9kv x .030 neon with 6 .030 gaps and cranked it up using
the house ground, and no filtering.  Of course I didn't get any discharge from
the big toroid.  I got a flourescent tube to get an idea of how the thing
was running and ended up holding it a tad to close to the toroid and pulled 
an 8" white hot arc off the toroid, through the bulb and through my arm.
I think the wife was more shocked than I was as she was standing there 
watching. Scared her a little I think. How's that for a very first arc?

Anyways I tuned in the primary at around the 13th turn and was able to get 
8" to 9" heavy arcs to a flourescent tube setting on a cardboard box nearby
or could get a 4" brush discharge off of a pointed object set on top.  This
is all I could get 270 VA to do.

Today I went out and got two 15kv x .030 neons (900 VA) and hooked them up
with 12 .030 gaps.  Still no breakout without some coersion.  I was able to get 
a fifteen inch heavy discharge to the flourescent tube on the box and
every now and again I would get heavy forked discharges into free air on the
other side of the toroid about 2 feet long while it was striking the tube.  Just
setting a pop can on top it was breaking out into heavy forks that were licking
the ceiling two feet away.

No more running this thing on the house ground.  I've got a 486 that won't
boot now and a smoke detector that goes off as long as the spark gaps are
firing.  The wife is complaining the RF is hurting her fillings and my five year
old son thinks it's awesome that the little red lights on the back of his LA Gear
tennis shoes light up whenever I'm firing even though he's on the other side of
the house.  Even so I'm having a blast!

Is anybody having problems with heating of the secondary?  After a few sustained 
runs of about 3 or 4 minutes the secondary got pretty hot and the wire and
polyurethane is bulging out in a few spots where I guess there is air trapped 
behind the wire.  The poly seems to be holding up pretty well to the heat but
there are about a half dozen bulges about the size of a quarter poking out now.

I'll report back after I get this thing on a dedicated ground out in the garage.
(I was firing in the kitchen, it's as big as my one car garage and a heck of a
lot warmer, got even warmer after my wife realized I was setting this thing up 
in there).

By the way I'd like to thank everybody here for the great conversation and info.
The only info I've had on this is from here and on Mr. Ukonnen's FTP site.  I've
always loved the pictures and hope to get some of my own out one of these days.
Thanks also to Richard Quick who pointed me here last summer as I picked up on the
last few dying messages on Fidonet where he was having an awful time trying to
educate a few people who just refused to be educated.

-Mike McCarty