My minicoil contest rules and results are at http://www.laushaus.com/tesla/minicoilcontest/index.htm
Using a partially deshunted 4/20 NST to yield 38mA Isc, Karl Lindheimer reports getting up to 18.125". I once achieved 16", but haven't been able to do any better. But the secret does appear to lie in going large with top load and pri/sec inductors.
FWIW, my mini coil NST pulls 1.75Amps @120V from the wall with no PFC. Not certain if this included the microwave oven fan for the spark gap, but that shouldn't account for much.
Regards, Gary Lau
From: tesla-bounces@xxxxxxxxxx [mailto:tesla-bounces@xxxxxxxxxx] On
Behalf Of FutureT@xxxxxxx
Sent: Wednesday, March 12, 2008 10:12 PM
Subject: Re: [TCML] 5" Sparks - Approx 35 watts input power: Tesla was correct!
Well now that you mention that, do you happen to remember
what the results were for the best small coils in Gary's small coil contest?
I don't remember if those coil's performances met my formula or not.
Maybe Gary can give some info here.
When I built my TT-32 coil, it only gave 27" sparks instead of the
32" I expected. It was built very similar to the TT-42 coil, but was
smaller and used less power. The results were below what my
formula would expect. It's possible there were higher losses in
the particular transformer I used, or something similar. I didn't
really look into that. Maybe it wasn't really missing the mark
by a full 5". Maybe it only missed by 2" or so. I've have to check
my notes. This happens to be one of the things which is clearly
annotated in my notes ( I think ). The operating voltage was lower,
and that may contribute to under-performance. So yes,
there is hope for the small coils, that they may properly obey the formula,
if they are built carefully enough.
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