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RE: Need Help.



Dear Unknown Coiler,

Is your spark gap firing at all?  If it is, you should get a little bit of
spark even if your coil is way out of tune.  Put a top terminal (toroid,
coffee can, metal salad bowl, etc.) on the thing and tape a pin or
thumbtack on it with the point sticking up.  Darken the room.  Try each
primary turn, one by one, until you see some corona on the pin point, then
fine tune for longest spark.  If you never get any corona, change your
capacitance value & repeat the process.

I ran your secondary numbers in WinTes and it predicted about 350kHz if you
use a top terminal, and over 600kHz if you don't.  Your cap seems too
small.  WinTes says you can use up to .016uF with your 10kV NST.  My own
measurements indicate 750ml wine bottle caps are only good for about
.0013uF each.  You'd need a dozen of them to achieve .016uf.  Also, your
gallon jug probably doesn't have as much capacitance as you might think.
Glass surface area--not container volume--determines capacitance.  Since
the volume of a round bottle grows much faster than surface area as size
goes up, you're better off with many small bottles rather than a few big
ones.  I suggest standard 12oz beer bottles arranged in six-packs.  A
carefully built six-pack is good for about .005uf, so three six-packs will
give you a nice, compact cap for your NST.

My two pence worth.

Best of Luck,

Greg

----------
From: 	Tesla List[SMTP:tesla-at-pupman-dot-com]
Sent: 	Wednesday, November 18, 1998 8:06 PM
To: 	tesla-at-pupman-dot-com
Subject: 	Need Help.

Original Poster: kc1-at-ime-dot-net 

	I need some help getting my first coil up and running. I'm using a 10000v
60ma neon sign transformer.  My primary is 1/4" copper tubing, in a normal
helix, about 10 turns spaced approx. 1/4" apart. The secondary is 3"PVC
with 21" of 24GA wrapped around it. I'm using two wine bottles and one 1
gallon jug for caps. The spark gap is constructed of two 'L' brackets and
bolts. 
	I turned on the power, nothing happened, there is juice going through it,
I touched a flourescent bulb to the primary and it lit.  How close to in
tune does a coil need to be before you can get arcs and sparks out of it?
Can anyone help me? suggestions for a discharge terminal? thanks!
	I went by diagrams and info found here...
http://www.altair-dot-org/tesla.htm#newcoil