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Re: T.C. goals

My goal is as follows:

I built a small coil 25 years ago. It used a pair of 6L6 tubes stolen from a
PA amp. The
secondary was hand wound with #26 wire on a 24" x 3" varnished mailing tube.
The primary
was wound with  #12 house wire on a varnished oatmeal box. The transformer
was
stolen from an old TV set -- 600 volt secondary. The caps were also HV ones
from a TV.
The two tubes worked in parallel in a Hartley oscilator running off of raw
AC. Tuning was
accomplished by sliding the the primary up and down the secondary until
maximum discharge
was achieved: about 3 inch streamers from a needle point atop the coil. I
believe the coil operated at about 100 KHz.

With this simple TC, I fascinated my freinds and neighbors. It would light
up small neon bulbs and flourescent lights from six feet away. I can also
remember doing the following neat things:

1) Electron enginge. Using a piece of aluminum foil cut into a spiral shape
and placed on my needle point with a small bead as a bearing, the streamers
would fly off the end of the spiral generating propulsion and causing the
thing to spin very fast.

2) Exploding match heads. A kitchen match was stuck on the needle point with
the head in the air. The streamer would climb up the match, heating it, and
eventually igniting it.

3) Ion tree. A piece of 30 strand litz wire was unfrayed and attached so
that many strands of wire stuck up in the air about two inches. These would
dance about violently as the streamers came flying off them, looked like a
tree blowing in the wind.

3) Plasma tubes. Various electron tubes, argon bulbs, etc, would glow inside
with sometimes wonderfully colored streamers. Yes, I held them in my hand. I
was never concerned in those days about RF damage to skin and nerves,
X-rays, etc. Maybe I was lucky or maybe the power of my coil was too small
to matter.

4) My favorite experiment was simply to let the streamers crawl all over my
fingers. Or to hold a piece of wire in my hand near the coil and watch the
sparkes fly off of it toward the coil (actually never completing the path
unless I got too close.)

I had a blast with it. So my goal is to build another and repeat these
demonstrations. I am
learning that a disruptive type coil may not be ideal for this. I may go
back to my original design
using vacuum tubes.

Bill Walker