RE: SMALL SPARKS: PLENTY OF POWER- NO TIME

["Tesla list" <tesla@xxxxxxxxxx>]

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

Hi Jeremiah:

I would also suspect that the primary tap may not be optimum.  With a 15
turn primary, one can vary 1-2 turns and not see a world of difference,
but since you say you use only six turns, it may be very sensitive to
fractional turns.  It looks like it wouldn't be too difficult to replace
the insulated wire you have with solid bare wire, at least temporarily,
or ideally 1/4" copper tubing, to permit quick and easy tapping at
arbitrary points.

It's curious that you've not reported racing sparks.  It's always been
said that the use of a helical primary will result in too-high coupling
and racing sparks.  Maybe no one's ever actually tried it?  I hope so,
yours is very compact!

I don't think that 20 Amps is at all out of line; I use at least that
much with my 15/60, and that's with PFC caps.

If you' really need to resolve this in 5 days, a more easily tapped
primary is my best suggestion.  But as time permits, I would strongly
suggest using John Freau's electronic phase adjuster.  Without a means
of varying the phase while the coil is operating, either electronically
or mechanically, I would imagine that it's extremely difficult to know
when you've hit the best spot.  Your top load also seems somewhat small
for the power level you have.  My 15/60 coil does well with a 7"x30"
toroid, and most folks report that performance increases with bigger top
loads.

Regards, Gary Lau
MA, USA

> Original poster: tesla popp <teslas_lab@xxxxxxxxx>
>
> I would usually troubly shoot this sort of problem
> myself, but I am almost OUT OF TIME!  I have a show to
> do in 5 days!
>
> One of my coils has a BIG problem, It's drawing
> 20amps, and making 3.5 foot sparks.  This is VERY BAD.
>   I have no idea why it is acting up, but I belive it
> might be due to bad coupeling?!  {note: the winding
> starts 1" above the bottom winding of the HELICAL
> primary}
>
> Operation of the coil is VERY STEADY, and is NOT
> erratic at all.  I am pretty shure I have my SRSG set
> where it should be.
>
> [Note: please trust the specs I am providing]
> -The tranny is a 15/120NST "Draws more with my L.T.R.
> MMC"
> -A 120BPS sallent pole syncronious rotery gap
> -Secondary coil 6.25" x 40" 20awg, 1250 turns
> -helical primary 12.5" wide, tapped at 6 turns "no
> room for a flat spiral primary."
> -MMC is .05uF
>
> note- USE THE PICTURE LINK I HAVE PROVIDED TO SEE WHAT
> I AM WORKING WITH.  Any ideas will greatly help!
>
> http://www.amasingscience.com/teslacoils/images/TWIN_FULL.jpg
>
> http://www.amasingscience.com/teslacoils/images/TWINBIG_PRI.jpg
>
> http://www.amasingscience.com/teslacoils/images/TWIN_MMC.jpg
>
>
> Thanks,
> Coiler Forever: Jeremiah Popp
>
>
>