RE: first light

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Lau, Gary" <gary.lau@xxxxxx>

Hi Andy:

I assume your temporary primary is solid, not stranded?  Stranded is
definitely not good.  Is there a reason for the wide 1" primary turns
spacing?  That will end up using more wire with somewhat (?) higher
losses, and when you re-do it with Cu tubing with 1/2" spacing, you'll
find you need a different number of turns.

Have you experimented with the pri-sec coupling?  Lowering the primary
until you get racing sparks, then backing off, will help performance.

I'd recommend using a higher capacitance, up to .01uF, though this may
not be a low budget item.

What is the surface of your top load like?  If it's very irregular and
you get multiple streamers and corona, that will reduce the performance.

A single static gap will require significant airflow to perform well,
and carriage bolt electrodes may require a more focused airflow directly
through the arc than a simple fan will provide.  Two parallel copper
pipes may do better.

Although I doubt the RF ground will affect performance one way or the
other (it mostly affects how much EMI gets into your power mains), I'm
not sure the 90lb anvil is an excellent choice.  I think a length of
aluminum foil (more is better) spooled out on the concrete floor will
provide a better RF ground.

Regards, Gary Lau
MA, USA

> -----Original Message-----
> From: Tesla list [mailto:tesla@xxxxxxxxxx]
> Sent: Monday, December 06, 2004 9:33 AM
> To: tesla@xxxxxxxxxx
> Subject: first light
>
> Original poster: "Andrew Genseal" <aggniu@xxxxxxxxxxx>
>
> Well, last weekend I finally got my first coil fired up.  During this
first
> light, I made a temporary primary coil from 14G (tapped at turn 12 I
> believe)wire just to make sure I would have enough turns before I went
and
> spent the time and money on copper tubing.
> Anyways, the specs of my coil are as follows: Transformer: 12kV 30mA
NST; 2
> parallel rolled poly caps for a total of ~6.44nF; primary: 12T 14G
copper
> wire spaced ~1" between turns; static spark gap consisting of 2 1/4"
> carriage bolts and a fan for quenching; 4.5" x 17.75" secondary wound
with
> 22G magnet wire; flex torroid of 15" avg diameter by 5" section
> diameter.  Oh yeah, Rf ground: 90lb anvil on a concrete floor with a
wet
> rag between them.
> At any rate, I tuned the system as best I could and found that at best
I
> was seeing 9" strikes to a grounded conductor.  Even then, the sparks
I was
> getting were very dim and looked more like corona than lightening.  I
> understand that this is not a high power system or one of ideal (or
even
> close to ideal) components but I was expecting a little bit more out
of the
> system.  The problem seems to boil down to the fact that being a
college
> student, my money is very thin and I am looking for the best
improvement
> for the dollar at this point. First step will be a 1/4" copper tube
primary
> spaced at 1/4" between turns.  After that, I don't know where the best
> direction to go would be.  I would greatly appreciate any and all
input on
> suggestions that might improve the performance of my coil based on the
vast
> expertise of this list.
>
> Thank you very much
> -Andy G.
>