Efficient Coil

From: 	davide-at-exit1.i-55-dot-com[SMTP:davide-at-exit1.i-55-dot-com]
Sent: 	Wednesday, June 18, 1997 5:13 PM
To: 	Tesla group
Subject: 	Efficient Coil

My son made a very efficient coil for his high school science teacher a
few years back. Even though it was constructed rather poorly, it was
able to produce 12 inch sparks from approximately 180 watts input. The
power supply was a 6000 volt, 30ma. neon transformer. The primary
capacitance consisted of 4, .01mf. 8,000 volt glass-tubed (mylar?) caps
in series. The spark gap was just a single static gap with brass bolts
set at approximately 1/8". The secondary winding length was around 12"
long x 3" diameter on schedule 80 gray PVC. The primary was a flat
spiral type with 6 turns of 12 gauge copper wire, tapped at the fourth
turn. The terminal capacitance was a oblate from a brass chandelier. 
The spark length was measured by a ruler held up to the output
terminal.  This would seem to better the 200 watt per foot of spark
length by 10%.

Dave Euans