Re: In search for a better PRIMARY

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Vardan <vardan01@xxxxxxxxxxxxxxxxxxxxxxx>

Hi,

Dest also looked into this:

http://www.pupman.com/listarchives/2006/May/msg00387.html

But I don't think he did it quite right...  The links are dead so I 
can't check now.  But I think he did the di/dt wrong.  If it was done 
right, I think his conclusion would be different ;-)))

I have seen miss-tuned coils do some very strange things.  Fat 1 foot 
arcs from the lower six inches of the secondary to the 
primary...  Primary to secondary arcs blowing holes though 1/4 inch 
G-10...  And of course racing arcs...  I think all this will be 
explained in a few days now :-))))))

Cheers,

        Terry

At 10:17 PM 8/13/2006, you wrote:
> Hi Terry,
>
> Yes, I think I have enough info to compute the initial voltage 
> profile.  It will be interesting to also add the wave propagation to 
> the model to see what happens over time and subsequent half 
> cycles.  My guess is that the problem is more complex than the 
> initial voltage profile but modeling the secondary into managable 
> number of segments may be a reasonable way to shed some 
> light.  Maybe we can share ideas on this and the modeling and I can 
> proceed.  You have a very intuitive perspective.
>
> Gerry R.
>
>
> > Original poster: Vardan <vardan01@xxxxxxxxxxxxxxxxxxxxxxx>
> >
> > Hi Gerry,
> >
> > You may be able to resolve the racing arc issue now.
> >
> > You know the di/dt of the primary coil.
> > You know the coupling to any arbitrary ring along the secondary.
> > You know the inductances.
> > You have a well known coil situation that is apparently close to 
> > the edge to study.
> >
> > If we assume the racing arc occurs in say the first 1/4 cycle 
> > (probably in the first micro second!), then the other resonances 
> > and harmonics have no effect since they have not had time to setup yet.
> >
> > Thus, the voltage gradient along the secondary in the first instant 
> > of firing is now taking into full account the primary to secondary 
> > geometry and coupling...
> >
> > MandK can be set up to find the data in a single run and you can 
> > modify the MANDK.INI file for further control.  You can just make 
> > the high increment the same as you coil section increment to 
> > calculate the right data directly.
> >
> > http://hot-streamer.com/TeslaCoils/Programs/MANDKV31.ZIP
> > http://hot-streamer.com/TeslaCoils/Programs/MANDKV31.PDF
> >
> > The coupling/length output data file can probably be imported to a 
> > spreadsheet.
> >
> > Thus, you should be able to graph the Voltage/UnitLength along the 
> > secondary for any primary to secondary configuration in the first 
> > instant the gap fires and from there determine if that is causing 
> > the racing arcs.
> >
> > If one cleans the gaps, the initial di/dt in the primary coil my 
> > increase. Thus your gap cleaning may indeed have increased the 
> > change for secondary racing arcs.
> >
> > I have always felt that the racing arc issue was a matter of pure 
> > transformer action.  So maybe you can prove me right :D
> >
> > Cheers,
> >
> >         Terry
> >
> >
> > At 11:53 PM 8/9/2006, you wrote:
> > > Hi All,
> > >
> > > Terry just put a writeup I did on my investigations using JavaTC 
> > > into what may be a better primary concept.  It is located at:
> > >
> > > <http://hot-streamer.com/temp/GerryReynolds/In_search_of_a_better_primary.pdf>http://hot-streamer.com/temp/GerryReynolds/In_search_of_a_better_primary.pdf
> > >
> > >
> > > If the idea works out, it may allow for higher coupling without 
> > > inducing racing arcs.
> > >
> > > Please feel free to comment or criticize (hopefullly 
> > > constructively) and If anyone is willing to try the idea, I would 
> > > be willing to consult.
> > >
> > > Gerry R