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Re: Fired, but need help



Patti,

I have had the same problem, and assure you that it is due to:  not enough
primary turns.  You are definetely undercoupled a little and that is making
some
of your secondary energy leave the secondary too before it gets to the toroid.
I suggest adding a few more turns on your primary and keep tapping in quarter
turn incriments outward until it goes away.  This should also improve your
spark
length dramatically.  Then you could try using some plumer's tape or similar
metal strap, so you can squeeze your primary down to a smaller outer diameter.
I have found this to dramatically increase results.  at the power your using,
I'd suspect double the spark length you got now.

Tesla List wrote:

> Original Poster: "Patti" <asrai-at-palmnet-dot-net>
>
> Hello Listers,
>
> This weekend the weather held out so I was finally able to achieve first
> light.  Results after safety gap, RSG, secondary height and toroid
> adjustments was 68" to a ground rod suspended on a ladder.  I did have a
> number of strike rail hits, so I raised the toroid up to a height of 18"
> above the top of the secondary.  My final voltage was about 196 VAC at 22
> amps to the 10KVA 14.4kv pole transformer that is current limited by a
> variable inductor with a range of .68 MH to 8.9 MH (setting was 6.9) and 2.9
> ohms of 10kw heater elements in series.
>
> One problem though, and I need some help.
>
> I'm getting numerous strikes along the outside of the secondary, starting
> with the top winding to the bottom winding.  Also I suffered some damage two
> turns about 5 inches up from the bottom of the secondary.  It got a bit
> cooked.  Right now I have the secondary bottom winding sitting about 1.25
> inches above the primary.  I'm running safety gaps at the caps at 1/2 inch
> and 5/16 inch on each side of the ground post tied to RF ground for the pole
> transformer.  The specs are:
>
> Capacitor: 2 .22mf 50KVDC csi caps in a series for .11mf total
>
> Toroid: 48" x 12" Aluminum duct wrapped with aluminum tape 53 pf
>
> Primary: 100ft of 1/2 diam. copper tubing starting at  7.3125 inch radius
> and ending with 19.8125 on turn #15.  Spacing between turns is .250 inches.
> Lpri needed for cap and toroid 50.8uh.  Currently tapped at about 8.5 turns.
>
> Secondary: 1000 turns of 22 AWG magnet wire wound on a 10.5 inch PVC duct
> that was coated with .125 inches of polyurethane before winding for a total
> winding length of 32 inches.  wire measures .032 in diam.  Coated with 1/16"
> of polyurethane.
>
> C=16.5 pf  Lsec+ 80.5 mh
>
> Resonance frequency of secondary with toroid installed: 67.3 Khz  Without
> toroid: 138.3 Khz
>
> H/D ratio: 3.0 to 1
>
> Used Medhurst constant of .61
>
> I've worked the calculations using the formulas from the archives, other
> list memeber's web pages and Wintesla program to make sure I'm getting
> approximatly the same results.  Any help would be appreciated especially on
> fixing secondaries and how to stop the cookage.
>
> Patti



--
Cabbott Sanders
Salem Oregon
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