[Prev][Next][Index][Thread]

First Power Up Test



Hello Group:

	Well, last night I was able to get enough time to set up and accomplish
my first test firing of my new coil.  It immediately shot out a 20"
spark from the toroid to my "test ground" which was simply a chunk of
#14 wire going from my earth ground to a point within 20" of the
toroid.  This spark was very thin and blue, but the multiple arcs from
the outer primary turn to the strike rail mounted about 1 3/4" above the
outer primary turn were wide and white--there seemed to be 3-4 firing
almost at the same time.  Apparently my next step will be to get the
primary and secondary resonant frequencies closer together!  My
secondary with the toroid resonates at 140 Khz so I then picked a tap
point to give a primary resonance at 130 Khz to compensate for the
charge build-up on the toroid which I understand typically drrops the
secondary resonance point.  My toroid is 48" in diameter using 6"
aluminum flexible duct as the outer ring.  I had seen up to about 220
volts going in and 4.5 amps and it was sparking--I stopped watching the
panel then and just watched the primary arcs!! Any opinions on whether I
should move my tap to a lower frequency first?  Since I am asking a
question here I'd better list some system specs too:

Power Supply: 14,400 VAC 10KVA pole pig limited with a Century Arc
Welder (set a minimum settings for first test)

Spark Gap: seven gap 1 1/2" dia. copper tube sytem with fan, in series
with a 	rotary--12 breaks/rev running slow--maybe 1500-2500 RPM???

Primary:  14 turns of 1/2" copper with 1/2" gap between turns.  About
11" I.D. and 40" O.D.------Tapped at 9 3/4 turns.  Condenser Products
.025 Mfd cap at 20,000 volts same as many in the group.

Secondary:  8" dia, acrylic form with 28" of #20 wire using a 48" dia.
toroid.

I figure if anyone could suggest going up or down in my primary
resonance point it might save me some time and possibly reduce the risk
of lots of generating lots of smoke!!  I already have apparently blown
the free digital volt meter I got!  Tonight I hope to try again so any
comments about your past efforts and knowledge would be appreciated. 
Thanks

Chuck Curran