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

Re: Racing Sparks

Original poster: "Barton B. Anderson" <bartb@xxxxxxxxxxxxxxxx>

Hi Jared,

Tesla list wrote:

Original poster: Jared E Dwarshuis <jdwarshui@xxxxxxxxx>

It is possible to get racing sparks without tight coupling.

Yes. In my opinion (because racing sparks are not fully understood), racing sparks can occur from poor tuning or high coupling, whatever causes a high voltage gradient along the length of the coil. Basically, anything that might cause a high voltage stress situation along the coil, is capable of producing racing sparks.

Larry and
I deliberatly made a 1.5 wave coil with a centered primary that had no
top end capacitors. What we found was racing sparks that existed only
at the quarter wave sections at the ends of the coil.(It looked like a
fiery Q-Tip).


When we added secondary capacitance the racing sparks
disapeared.  (Draw your own conclusion!)

You dampened or moved the gradient to a less stressful area?

I have noticed that tightly coupled coils are fussy about tuning. They
want the primary to be tapped in just the right place, and the spark
gap needs carefull tweaking.

Lose coupled coils are more forgiving  about tuning.

This may be very true. We haven't had a lot of fast energy transfer coils on the list to compare. A few, but not enough to get a good comprehension of the mechanism differences. Faster energy certainly dictates more power per time. I didn't notice this tuning range with my hybrid maggy (a close coupled 3 coil system). K was about 3.5 for this system, which interestingly was half way between the classic 2-coil systems and classic 3-coil maggies.

This hybrid is imaginable when coil 1 and 2 (drivers) are resonant with coil 3 in close proximity (and vise-versa). That is the hybrid that liked a mid-k value. I ran a 9" x 30" toroid on a small 4.5" coil. Same coil as a matter of fact I was discussing with D.C. I still have the maggy driver coils stored in cabinet, so I could always throw it together if needed. It was kind of fun to watch a really small coil break out with a large toroid!!!

Take care,