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!!!HELP A DESPERATE COILER!!!



  Hi!

 ---Sorry for the long message, but PLEASE read on---

 I've being on this list for about a week and haven’t yet introduced 
myself, so I'll do that first:
 Ok. My name is Sam Barros and I live in Holland (although I am not 
Dutch). I experiment with electricity, chemistry, physics and other 
fields of science as a Hobby. I have being doing research and 
experimentation with High Voltages for over 4 years now and I decided it 
was time to build my first Tesla Coil. I have a good understanding of TC 
theory and workings, and am fully capable of building and operating a TC 
without getting myself killed by electrocution (my first High Voltage 
electric shocks were my last ones), but there are a few issues I would 
like to get reviewed by someone with greater experience in the field 
than me (i.e. Just about everyone on this list who has actually built a 
Coil).
 Ok. My design aims for a medium power, very reliable, good-looking 
Tesla Coil. I'll be tapping its energy to conduct electromagnetic 
repulsion, confinement and acceleration of plasma, so ground strikes 
shouldn't be much of a problem.
 The main thing I am looking for here is efficiency. I want this coil to 
be as efficient as possible. Therefore I've given it a 3:1 H/D ratio and 
an angled primary, together with the use of  0.60 (between AWG 23 and 
22) wire (any thicker would be seriously wasted by "skin effect")
 Well, here are the specs for my coil so far:

 Secondary:

 Coil form:
 Diameter: 20cm (8in)
 Winding Length: 60 cm (24in)
 Wire gauge: 0.60mm (between 23 and 22AWG)
 Spacing between turns: NONE
 Secondary turns: 1000
 Secondary wire length: 627.69m (2028.57FT)
 Approximate resonant frequency: 186.11KHz
 Secondary quarter wavelength resonant frequency: 119.49KHz
 Secondary self-capacitance: 12.84pF
 Toroid capacitance required to form quarter wavelength coil: 18.31pF

 Primary:

 Primary capacitance: 0.0127uF
 Primary resonant frequency: 119.49KHz
 Primary conductor diameter: 8mm (0.320in)
 Primary turn to turn spacing: 8mm (0.320in)
 Spacing between the secondary and inside turn of primary: 55mm (2.2in)
 Primary tapped between turn 14 and 15 to form a resonant circuit at 
119.49KHz

 Neon transformer/Capacitor matching

 Transformer input voltage: 220V
 Transformer output voltage: 15KV
 Transformer operating frequency: 50Hz
 Transformer output current: 60mA

 Ok. Now the problems begin:

1- I have 2 ferrite cores, such as those used in radios. They measure 14 
x 1cm (5.6 x 0.4in) and I also have 60 meters of 0.60mm (AWG 23/22)wire, 
left from the Coil. Can I wind 2 good chokes using them? Would I need 
more? I can get more of them, or a different wire, but no different 
ferrite cores. How much inductance would be ideal for my coil? I think 
2mH should do, but I could be wrong...

2- Mike Hammer suggested I used the following primary: 18 turns of 8mm 
(0.320in) thick copper tubing spaced 8mm (0.320in) from each other, and 
with 3.5cm (1.4in) clearance from the secondary and a 15 degrees angle. 
I agree that's a better option, but I am not sure if it's the best 
option. I feel I can make the secondary/primary clearance less. Perhaps 
0.5in if I insulate the primary (the secondary is already very well 
insulated with epoxy and PU sealer). And, such a primary would have a 
diameter of about 80cm (32in). That's HUGE!!! It would need such a 
massive base. Is that really the best configuration, or can I make the 
primary coil shorter and therefore increase inductance? I want the most 
efficient design, remember!

3- Here in Holland the largest transformers available (because of legal 
restrictions) are rated 8KV/50mA. I've being to all 13 Neon Shops within 
a 50 KM range (it took me 5 days) and NOT A SINGLE ONE OF THE WILL GIVE 
OR SELL ME A USED TRANSFORMER. Let alone the 3 I would need to run my 
coil. A single new transformer here costs 300 dollars (rated 10KV, 
100mA. They come from Italy and are impossible to get without and order)
 Can some kind soul sell me a 1000W working, used neon transformer? 
PLEASE!!! I really need this, and there is no other way I can get it.. I 
can pay about 50 dollars. It will cover the costs of transportation, and 
should leave some extra for the kind soul that made my Tesla Coil 
Project possible.

 Thank you very much for taking your time and reading such a long 
message (supposing you didn't just scroll down looking for the "delete" 
button). Please help me if you can... Any questions, comments, hints are 
very welcome.

 THANKS!!!!

 Sam Barros

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