shorted primary turns = bigger sparks strangeness

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

Original poster: "Crow Leader by way of Terry Fritz <twftesla-at-qwest-dot-net>" <tesla-at-lists.symmetric-dot-net>

I've been playing with a very out of proportion coil made out of scraps from
previous projects and noticed something odd somebod might be able to comment
on.

The secondary is 4.5" PVC wound to about 30" of 20 guage wire, and primary
is tape wound from 1/4" flat copper buss bar about 14" in diameter with a
inner diameter of about 10" with about 6 turns.

For fun I put a 6" x 24" toroid on top. The self resonant frequency is about
240kHz for everything when tuned.

In any case, at low power levels to keep sparks under 1 foot, I get better
performance with one turn in the primary shorted out and the tuning tape set
elsehwere to meet the approximately 240kHz. If turned normally, the sparks
are smaller. strange.

what might cause this?

Also, since the top load capaciance is so large, I've noticed the waveforms
takes a few cycles to even ring up to a full voltage. I'll post pictures of
this as it's amusing as well.

KEN