1st light on DC MOT coil

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Original poster: "Wells Campbell by way of Terry Fritz <twftesla-at-qwest-dot-net>" <wellscampbell-at-onebox-dot-com>

Ahh, the smell of ozone in the morning...

All, 

	First, many thanks to the list for occasional advice and a wealth
of info, I have been largely a lurker, but now that I have something
to show, I will try to give some back... 

	After a binge of activity this weekend (mostly on my rotary gap),
I finally got to the point where I could cobble up my setup and fire.
As it was about 11:00 last night when I finished, I couldn't do anything
until this morning. ( I reside in a studio apartment, and would bet the
neighbors wouldn't be as excited as I would...) anyway, I woke to the
music of power tools and a jackhammer wafting in on the breeze, and knew
that at least I wouldn't be the only noisemaker...

My coil is a compact DC MOT powered magnifier that uses a doubler / filter
arrangement and charging choke for power, an asynchronous rotary gap
capable of up to 1300 BPS, and (soon to come) off axis tuning that will
be operable as the coil runs. 

The power supply is similar in design to those being utilized by Greg
Hunter, Steve Ward, Marco Denicolai et al. I designed it to be very modular
and adjustable, including capacitive ballasting, and the ability to configure
as either a "level shifter" giving 60 hz pulses of DC every other half-cycle
or as a "half-wave doubler / filter" giving DC every half-cycle. (terminology
check?)

Ballasting is accomplished by placing up to four of the MO caps in series
in the circuit, limiting the amount of power pumped through the system
each cycle. series-parallel combos can be used to increase the power
in steps. 

My coil specs are as follows...

Primary: solenoid (cylinder) type, 1/4 " copper tubing wound around the
base chopped off of a 5 gal bucket, 10 turns, 11" diameter, 5" winding
height. Tapped at turn four for this run.

Driver coil: 150 turns 22 awg magnet wire, space-wound with fishing line
and covered with epoxy, on a smaller bucket that just fits inside the
primary bucket. Average diameter 9", height 7.5". The driver bucket is
inverted in the primary bucket, so that the coils diverge slightly. the
primary coil can be inverted as well, so that the driver sits atop the
primary for looser coupling. (pics soon) 

Tertiary coil: 3" diameter 16.25" winding height 28 AWG approx. 950 turns,
epoxy covered, on a thin clear form (HDPE i think, or maybe polycarbonate?)
sold as a mailing tube at my local plastics place. (I made two of these,
they are nearly identical, grin) 

Topload: 3" minor diameter, 11.5" (outer) major diameter toroid made
with dryer ducting covered with spackling paste, then AL tape. 

Tank Capacitor: Al foil and plastic picnic plates sunk in mineral oil
in a bucket, definitely the weak link in the system, MMC pending. My
   crap-tacular DMM says 16 nF, with grain of salt. 

Rotary: 11,000 RPM angle grinder, 3/8" by 4.5" dia. lexan disc with (handmade)
copper electrodes that protrude straight out 1 inch past the rim of the
disc. They are flat, like paddles, and pass through gaps also made with
flat pieces of copper, so that the edges line up as the "paddle" passes
through the gap. This produces a fair amont of wind, and should cool
all electrodes (essential with lexan) as well as help with quenching.
Disc has four electrodes, and they pass through two stationary gaps,
for 8 presentations per rotation. 

for the first light, I didn't have much for power control, just a little
variac which has been smoking alot lately (grin). I need one for the
gap and one for the coil, but this time I ran the gap at about 1/2 speed
in series with a small blower motor, and cranked up the coil power with
the variac. 

Behold! 8" purple waving tendrils that circled the toroid, about two
at a time, very nice shape, curvy, with a few branches each. Arcs to
ground rod were about 10-12 in. in length and purple-white, and rose
similar to a jacob's ladder, where they would go out and re-attach at
the bottom. Arcs from the driver top to ground were about 4" and thick
white and loud. Runtime was about a minute, and everything stayed cool.


Still to do: better cap; power control box with breakers, line filter
and variacs for coil and rotary; shield driver coil better; sink MOT's
in oil; attach blower to rotary gap and encase in muffling case, with
welding glass in window so sparks can be observed; strike ring for primary;
corona rings for top of driver and bottom of tertiary; costruct "dial
a tune" off axis adjustable inductor; to name a few.

I will take pics of components, could someone let me know how to post
them? 


Cheers, 

-- 
Wells Campbell
wellscampbell-at-onebox-dot-com