first light of our first coil!

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

Original poster: "Dwight Harm by way of Terry Fritz <teslalist-at-qwest-dot-net>" <dwighth-at-traxsoft-dot-com>

We finished our first coil & fired it up!  We've gotten consistent 10-11"
sparks from a break-out point to a grounded pole, but we should be able to
do a lot better.  Here's some pics of the coil, no good spark pics, as my
cheapie digital cam won't do long exposures...
http://f2.pg.photos.yahoo-dot-com/proteledauser -- click on "tesla coil" album.

Many thanks to all on this list for such great information!

Next step: improve gap to better "sucker" or "air-blast" style -- I think
we're not quenching sufficiently.

Specs:

Power: 2 MOTs with voltage-doubler, and 4 MO caps for secondary ballast,
120V input; I think the output is over 1 KVA, but we haven't measured the
shorted current in this particular configuration. (With 3 MO caps, we
measured 3450V -at- 490ma, for 1.7 KVA.)  No PFC cap.
Primary: 10 turns 3/16" copper pipe spaced 1/4", ID=6.5", tuned at 9.5.
Secondary: about 1575 turns 28awg, 23" on 4.5" PVC
Tank cap: beer-bottle/saltwater, 3 5-gallon buckets with 13 bottles each,
total of 46nf (measured).
Gap: crude static gap, copper end-cap to large brass bolt, with vacuum
cleaner for quenching.

top load: we had hoped to find a styrofoam core of the right size, but they
were all too skinny (about 2" diameter).  We happened to get 2 that exactly
fit one inside the other, so we wrapped that configuration in aluminum tape.
The cross section is more-or-less oval, 2" by 4"; major diameter is 12"
(measured to the middle of the "oval").

total cost: $99

Dwight & Greg