MOT coil performance

["LOCKWOOD, Chris J." <clockwood-at-orbeng-dot-com.au> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

Hi,

I'm going to make a new coil from scratch, based on 2 MOTs, and a 0.1uF 20kV
cap, which I already have.

What size sparks should I expect from an 'optimised' coil/gap config? 

Given the low voltage (~6kV pk) from the supply, I'd assume that the coil
would need to be tuned to quite a low F, to get the primary (= gap) current
down. Any suggestions (from experience) as to the most efficient
configuration of gap, primary L, and secondary dimensions?

My 4.5" coil fried last night. At best was only getting 30" ground strikes
from a twin static gap and this supply. I'm sure this could be much better,
with a more 'optimal' setup... Gave up on the DC supply for now~ MOTs are
more compact.

Chris
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