Re: Helical top loads

["Michael Deegan" <mdeegan-at-xxxxxxxxxxxx> (by way of Terry Fritz <twftesla-at-xxxxxxxxxx>)]

John,

Right now my coil is tapped at turn 14/15. With my large toroid i can only get
1" sparks. Is there any other way of tuning the coil? I was thinking maybe of
adding a EMMC and im still looking for a 15/60 NST.

Tesla list wrote:

> Original poster: FutureT-at-aol-dot-com
>
> In a message dated 11/23/00 10:28:17 PM Eastern Standard Time,
> tesla-at-pupman-dot-com writes:
>
> > How can I tune my coil for max. length?
> >
> >  Is my 3.5" X 20.5" toroid too big for my 12/30? Should i get more power?
> >
> >  What is the max. streamer length i can get off of a 12/30 on a 6" coil?
> >
> >  Thanks in advance,
> >  Michael Deegan
> >
>
> Michael,
>
> The tap point position along the primary has to be adjusted
> (moved) to find the best spark output.  IN other words, use
> a suitable number of primary turns for best spark output.
> Some turns may be unused.  An important point is that if
> you don't have enough capacitance, then you may need more
> turns than you have in the primary.  The easiest solution in
> that case is to add more capacitance until the coil tunes,
> and the spark output increases.  You didn't mention where
> your tap point is now.  If you're right at the outer turn, and
> if tapping inwards reduces the sparks, then adding enough
> more capacitance will give you enough tuning range.
>
> The toroid is not too large, I've used a 5" by 20" dryer duct
> toroid with a 12/30 in the past, and gotten 42" output sparks,
> (37" sparks with a static gap).  42" sparks are the longest
> I've gotten from a 12/30 NST.  My coil that uses a 12/30 NST
> is at:
>
>    http://hometown.aol-dot-com/futuret/page3.html
>
> John Freau