Re: Beginner seeking advice...

["Øyvind Kaurstad" <oyvind-at-xxxxxxxxxx> (by way of Terry Fritz <twftesla-at-xxxxxxxxxx>)]

> Original poster: "Jan Florian Wagner" <jwagner-at-cc.hut.fi> 
> 
> Hi,
> 
> > No, it's not *that* bad, but I'd like to get sparks into the air.
> > And yes, you may be right that the power is insufficient.
> 
> Did you already try the LED (or other similar) test - two opposing
> leds in parallel connected between secondary base and ground, as an
> indicator whether your coil is really in-tune or not? 

No, I didn't try that...

My ground is a relatively big wooden plate with ordinary household 
aluminium foil on it. My secondary is capped with aluminium tape, and 
is standing on the ground plate. The groundplate is otherwise 
unconnected. Do you mean that I should connect the LEDS across the 
short between the groundplane and the secondary base? Will there be 
enough voltage across this short to make the LEDS illuminate?

Will this test give me more/better information than the fluorescent 
lamp test? If I hold a light tube closer than 30 cm from the top load 
it will illuminate when the secondary resonates.
 
> Did you say you had a pancake primary coil? Helical (and close to the
> secondary but well insulated) might perform better, a bit like in
> vacuum tube coils. How about a short piece of ferrite rod inside the
> bottom part of the secondary?

That may be a good idea. I have a flat pancake now, but I could try a 
helical instead. How many turns, and how close to the secondary 
should it be? If I can find a ferrite rod I can try putting it in 
there and see if it makes any difference.
 
> > I am actually using one of it's more modern siblings, the 3843,
> > which will go beyond 500 kHz.
> 
> Oh that's nicer - sorry but I mistook you for a 555 timer + TV flyback
> / 2n3055 based oscillator guy... ;o)

:-)
 
> Solid state continuos wave coils need drastically more power input to
> get the same streamer length as from spark-gap coils. The problem is
> also how to move along with the resonant frequency according to
> streamer/spark load, so that you get maximum output. Duane A Bylund
> had some experimental stuff on this (very old...), a PLL / VCO setup,
> and it is shortly described in his "Modern Tesla Coil Design Theory"
> book (http://www.teslabook-dot-com/). It does not look too impressive, but
> it might even work.

I'll look into this.

Thanks for your assistance. It is appreciated.



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Øyvind Kaurstad, oyvind-at-safetel.no

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