[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [TCML] Secondary and Primary Assistance
Parallel copper pipes work fine. Just blast 400-500 CFM of air thru them.
About the very best is a hyperbaric type sparkgap using an old vacuum
cleaner motor (your local vac cleaner repair shop should have a good
supply). These provide great quenching and almost optimum performance
unless you go to solid state type sparkgaps using IGBTs.
Use a height/dia ratio for the sec coil of 4 or 4.5:1. Use the largest dia
sec you can as the potential is Vsec = -L x dI/dt. In short, keep the
inductance of the sec large. Even with small NSTs a 6-8 inch coilform dia
gives excellent performance. Most experimenters prefer around 1,000 to
1,200 turns for optimum performance. Example, if you use a 6" ID PVC tube
with 6 3/8" OD, then with a 4.5:1 H/D ratio, this gives you a winding length
of approx 29 inches. Divide this by 1,000 turns which provides a wire dia.
of .029 inches. Use a "double build" enamel magnet wire such as
Polythermalize (Beldon). Closest one for this example would be # 21 AWG.
You could also use 22 AWG.
Then use Bart's JAVATC to do all the calculations which gives res freq,
number pri turns, pri-sec spacing, cap size, coeff of coupling, toroid
capacitance, and everything else you need. If you are not familiar with
JAVATC just fire me an off-list email back with your tel number and I will
call a guide you thru it. After you have used it a few times you will just
love it. Fast and extremely accurate, usually within 1/8th turn on the pri
Regards and happy sparks,
On 3/15/08, Mike H <mike8675309@xxxxxxxxx> wrote:
> I am very new to coiling. It is something that my Father and I talked
> about doing many years ago, but never found time to do something like
> that. Recently I found someone selling a coil they had started
> building, but hadn't quite completed. He had all the components.
> Now last year I completed the construction and fired it. It worked
> o.k., but I knew I really didn't know what I was doing.
> My main issue is I have a secondary that the original construction of
> is unknown. Thus it is difficult for me to verify any numbers. Also
> my secondary took some hits, and I would like to wind a new one. The
> actual device itself is also kind of large, so my goal is to re-wire
> everything to make it more compact, and then create a new primary and
> secondary that is optimized for the NST I have.
> So I find myself with 3 questions:
> #1- What is an optimum design for a static spark gap? Copper pipes?
> Brass knobs? titanium electrodes?
> #2- For my equipment, either What would my optimum primary layout be,
> or how would I calculate this?
> #3- Based on the primary design what would my optimum secondary be or
> how do I calculate this?
> Thank you for any assistance
> Mike H.
> Farmington, MN
> Details on what I have to work with:
> Some pictures of the components Here:
> Video of the first fire last fall.
> Transformer is:
> Franceformer 12030P
> 120v NST 12000v 30mA, 360VA
> I am using a NST filter based on the Terry Filter design:
> 14 MOVS
> 12 CAPS 1.6KvDC
> 2 1kohm 100W resistors
> Dual Safety Gaps
> My Spark Gap
> Brass Cabinet Knob for Spark Gap - Microwave Fan
> Primary Coil
> 1/4 Copper Soft Tube
> 14.25" diameter coil
> 1" spacing from Secondary
> 13 turns
> Secondary Coil
> Unknown turns
> 16" of turns
> 19" Total Height
> Top Load
> Aluminum tape covered toroid made from MDF and 4" Aluminum duct
> Tesla mailing list
Tesla mailing list