Re: More details for diagnosing coil problems. (fwd)

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---------- Forwarded message ----------
Date: Wed, 13 Dec 2006 10:11:17 -0600
From: Harold Weiss <hweiss@xxxxxxxxxx>
To: Tesla list <tesla@xxxxxxxxxx>
Subject: Re: More details for diagnosing coil problems. (fwd)

Hi John,

Be careful with the capacitor voltage rating!  The cap should be at least 
twice the NST voltage.  Lower the sphere as much as possible.  Also check 
your tunning.  You should be able to get 8-10" streamers into the air if 
everything is tunned right.  Also, check your gap and open it to the point 
where the NST can consistantly fire it without the primary cap/coil hooked 
up.

David E Weiss


>
> Primary Circuit:
> NST: 7500V, 250 VA - 30 mA
> Two .005uF Pulse Discharge CAps (rated at 10,000V) in parallel to get 
> .01uF
> 7 inch radius flat coil made of 1/4 inch copper tubing, - 6 turns
> spark gap made of  7 pieces of 1/2 inch copper pipe. .09 inch total gap.
> RF line filter and 22.5 uF power factor capacitor
>
> Secondary Circuit:
> Coil: 3.5 in diam, 17 in height, 630 turns of 22 ga magnet wire. wound
> around pvc, not shellacqed
> 7in diam very smooth aluminum ball
> 4 in between top of coil and bottom of ball
>
> I measured the resonant frequency of both circuits with a scope to be
> about 460 kHz.
>
>
> -John
>
> ******************************
> John Welch
>
> Cabrillo College Physics Dept.
>
>
>