RE: High midnight at the Texas corral

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

Original poster: "Bert Pool by way of Terry Fritz <teslalist-at-qwest-dot-net>" <bert.tx-at-prodigy-dot-net>


>[snip]



>  The 12" secondary is  closewound w/ #16 magnet
>wire and is only 38.5" tall but suffers NO racing sparks! I do
>have trouble with a lot of the strikes hitting at the shield
>ring around the primary coil though, due to its relative short
>height. I can get 8 to 10 ft. sparks with about 7 to 8 kVA in.

It's hard to build a high performance coil as short as you describe and not 
have racing sparks or spark related break-downs.  You must have it tuned 
very well!


>.015 uFD is a very impressively low tank cap value for 15 footers
>and I would say one would be hard pressed to get this kind of per-
>formance from a classic two-coil system. What kind of spark gap
>design do have for this system? I seem to recall that R. Hull
>mentioned that monumental efforts at quenching were required to
>get this kind of performance from a maggie w/out the detructive
>"racing sparks" rearing their ugly heads. I assume that you are
>running high speed asynch rotary?

Six inch diameter rotary - two sets of stationary gaps, i.e. a total of 
four air gaps.  I use a copper pipe cylindrical gap in series to aid 
quenching.  No where near as exotic as Richard's advanced gaps.


>Also, how brilliant are your 15 ft. sparks? Are they as brilliant
>as the 12 footers from Bill's Warthog?

It's hard to find a coil with sparks that bright.  Kevin's Biggg coil 
manages to equal or excel that brightness.


>I would love to someday try my hand at a maggie if I had the
>room. Maggies are space hogs, you know :-O

The drivers are large.  I guess that's the one thing I'd love to see some 
improvement in.  I've tried reducing the size by using oil, but that was a 
messy failure.


>David Rieben