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Sparkgaps and Chokes (new subscriber)

Hi everybody, 
may I introduce myself to the tesla list, please. My name is Herbert Mehlhose. 
I'm 36 years old and live in Germany. Currently, I spend lots of my spare time 
with coil building. 
I already have build a small coil with about 300W. Now I'm working on the next 
larger model, with a power level of 2kVA. I have 2 questions / discussion

1. Sparkgap 
I'd like to build a rotary gap for my new coil. Since I will not use a neon 
transformer it should be ok although the power level is not REALLY high. 
(My transformer is 15,4 kV/130mA. It is a transformer used for ozone
When thinking about rotary operation, I had the following idea: 
The gap will be asynchronous. As the distance of electrodes should be very
the gap could fire at much lower voltage than peak capacitor voltage, which
not be optimum for maximum bang. To set a minimum voltage level for firing,
like to put a static gap (Richard Quick type) in series with my rotary which
prevent firings at too low levels. But in this case, it is possible that the 
gap will miss the point of maximum voltage and the cap could discharge with
decreasing portion of the sine wave. 
To avoid this the bps should be high enough to ensure, that the angles of 90
and 270 degrees (the voltage maximums) would be met with a maximum
deviation of 
let's say +/- 15 degrees - i.e. 1200 bps would be needed at 50Hz - 24
at 3000rpm. 
This would result in a behaviour similar to a synchronous gap without the need 
to build a synchronous one. 
I have read, that series connections of rotary and static may be used at very
levels of power. Does anybody have experience with that? What do you think
that approach? Totally nonsense or worth starting to build? 

2. RF chokes 
I did not find ferrite cores that made possible a high enough inductivity of 2
to 10 mH. But I do not want to use air cored chokes (with series resistance to 
lower the Q). 
So I plan to use the metal blades used for transformer cores. I got some of
from a transformer company. I wound chokes on PVC pipe and just will fix the
blades inside. 
Do you think the magnetic behaviour (saturation etc.) will be ok for this use? 

Thank you very much for any ideas, 
save and powerful coiling to all of you, 


Please visit my homepage, which is online since 3 weeks: 
This has information about my small first model and will be updated with
about my next project.