Re: Does anyone recognize this problem? Solved?!

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: Mark Broker <mbroker-at-thegeekgroup-dot-org> 

Perhaps 32.0nf?  That's just about right for 15/140 input.

I would try experimenting with a second, smaller toroid below the main 
toroid.  With experimentation, this should help prevent the problems you 
are experiencing.

Regards,

Mark Broker
Chief Engineer, The Geek Group


On Sat, 06 Dec 2003 12:42:11 -0700, Tesla list <tesla-at-pupman-dot-com> wrote:

>Original poster: "Gerry Reynolds" <gerryreynolds-at-earthlink-dot-net> Hi Robert,
>
>Is this the coil with two 15kv 70ma NST's and a Cp of 320nf?  If so, isn't
>320nf much larger than the recommended LTR value of 65 to 80nf with a SRSG?
>(Cres=25nf assuming 60 Hz)
>
>Gerry R
>Ft Collins, CO
>
>
>
>  > Original poster: "Robert Hanford" <pomnept-at-comcast-dot-net>
>  >
>  > Hello all!
>  > Thanks for all of your replies.  They were all very helpful.  I have been
>  > able to run my coil 3 brief times since fixing what I believe and hope was
>  > the problem.  John (fireba8104-at-yahoo-dot-com) suggested that the inner turn of
>  > the primary might be connected to ground.  I did indeed have a brass bolt
>  > attached to my wooden cabinet connected to RF ground.  The inner turn of
>my
>  > primary also contacted my wooden cabinet.  After I put a plastic tube
>around
>  > my brass bolt, the problem seems to have disappeared!  The next logical
>step
>  > would be to insulate the inner turn of the primary but this is a bit more
>of
>  > an engineering problem.  The coil still has strike rail hits but they seem
>  > to be more normal.  I would like to know how often people get strike rail
>  > hits and for how long a duration.
>  >
>  > Sincerely,
>  > Robert Hanford
>  >
>  >
>  > ----- Original Message -----
>  > From: "Tesla list" <tesla-at-pupman-dot-com>
>  > To: <tesla-at-pupman-dot-com>
>  > Sent: Saturday, November 29, 2003 6:06 PM
>  > Subject: Re: Does anyone recognize this problem? Tried again!
>  >
>  >
>  >  > Original poster: "Robert Hanford" <pomnept-at-comcast-dot-net>
>  >  >
>  >  > Hi all, thanks for your replies. After reading them, the first thing I
>did
>  >  > was check the inside of the 2ndary form.There were some burn marks and
>I
>  >  > sandpapered them out . Next I tried retuning, and I think my original
>  >  > mistake was to set the spark gap so tiny that at 30% the breakout point
>  > was
>  >  > a tiny fizzle. Widening the spark gap slightly produced a much more
>  > visible
>  >  > output. I think Dr. R. had a recommended distance for 30% power- I'll
>have
>  >  > to look it up...  Then it worked great again but after a short time the
>  >  > toroid again started bombarding the strike rail, then the secondary! :
>^
>  >  > (    I'll examine it AGAIN tomorrow or tonight if I'm in good graces w/
>  >  > wife.Thanks anyone for any further ideas!
>  >  > ----- Original Message -----
>  >  >
>  >  >
>  >
>  >