getting the bugs out- a little help

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Original poster: Tesla729-at-cs-dot-com 

Hi all,

I am in the process of rebuilding my piggie system and
I fianlly got to start firing her up and tuning it in this eve-
ning. I now only have a 9x30 toroid and I know that's a lit-
tle small for my 12.75"x48.5" secondary coil as I'm think-
ing more along the lines of a 12x48 toroid to properly
utilize the avilable power from my coil. I did get a few
8 to 9 ft. strikes to a metal ladder in my driveway this
evening on just a rough tune-up.

There are a couple of problems that I encountered
though. First, my Wysock-built rotory gap is sync at
480 bps and w/ .0825 uFD primary capacitance, I'm
thinking that's a little too fast for the capacitor to ever
be able to fully charge before discharging across the
SG and that would definitely limit my sec. voltage gain.
I haven't built a Freau phase adjuster yet either as I'm
not sure that the phase angle would even be that big
of an issue at 480 bps. I'm thinking about removing
4 of the 8 rotory electrodes to go for 240 bps. Maybe
some of you you more mathematically inclined mem-
bers can tell me what the best bps rate range should
be for this coil. My power supply is a 10 kVA, 14400
volt PDT controlled through (2) paralleled 1256 variacs
(up to 280 volts -at- 56 amps) and ballasted w/ a seriesed
225 amp arc welder w/ the welding leads shorted. It just
seems that I ought to be able get brighter,longer, more
powerful sparks w/ my available power. Of course, like I
said, I just roughly tuned it in tonight.

The one other little problem that I did encounter when
I really began to pour the juice to her was that the
grounded strike ring would start flashing over to the
outer turn of the primary coil. I thought that I had
plenty of claerance here (about 3" or so) but maybe
that autotransformer action is a little bit more of a problem
than I thought. I'm tapped at just over 9 turns on the pri-
mary, so I only have right at 3 more turns to build up
voltage between the outermost primary turn and the strike
shield ring. I have the 1/2" ID copper tubing primary secured
w/ plastic cable tie-downs to 1 1/2" white PVC pipe through
pre-drilled holes to run the tie-downs through. The ground ca-
ble that connects to the strike ring is #6 green insulated
stranded building cable and it runs though the bottom of one
of the (8) 1 1/2" dia. PVC primary supports. Could the problem
be here as the outer primary winding may be arcing to the
grounding cable though one of the pre-drilled mounting holes
in the PVC pipe? It was kind of hard to tell the exact location
of the annoying bright flashover that was taking place when I
turned the power up, but I could tell it was around the outer
primary turn and the grounded strike ring. This annoying flash-
over was what was causing EM problems in the house, too.
As long as this flashover didn't occur, nothing electronic in the
house (like the alarm system going off) was bothered.

I just finished building my RF ground system today. It con-
sists of (4) 5/8" dia. x 8ft. long copper-cald grounding rods
driven all but about 3" worth into the soil. They are inter-
connected w/ a bare #1/0 welding cable about 10" to 12"
under the ground. I run an 18 ft. long piece of insulated
#1/0 welding cable from the RF grounding post on the coil
to the RF grounding rods and I think my ground is sufficient
for my coil.

On a positive note, I didn't have any trace of racing sparks
on the secondary at any power level so I'm not overcoupled.
The bottom-most secondary coil is about 1 3/4" above the
top of the innermost primary coil. I could even try to increase
the coupling a bit but I don't think that the secondary needs
to be lowered much more relative to the primary coil on a coil
of this magnitude. No racing sparks are good ;^)

Sorry for the long post but I knew if anybody could help w/
this, it would be you guys on this list ;^)

Thanks in advance,
David Rieben