Gary, all,

Maybe the robustness of a particular NST is having an effect here.
I had an old 12 - 30 NST that was able to charge a .0085uF cap, and
give 38" sparks using a static gap.  But a more modern 12 - 30 NST
gave only about 28" sparks in the same TC.  But when I went to the
sync gap setup, the newer, weak NST gave 42" sparks.

Maybe 15 - 60 NST's have a wider "charging-window" and can better
handle LTR caps than the 12 - 30 NST's.  Or your NST may be robust
in its current capabilities.  This may explain the differing results we've
gotten, and explain why your results did not match your simulations.
Maybe the simulations do not account for unexpected robustness in
an NST.

John Freau