coil size for orbits? (fwd)

From: 	FutureT[SMTP:FutureT-at-aol-dot-com]
Sent: 	Tuesday, January 20, 1998 7:51 AM
To: 	tesla-at-pupman-dot-com
Subject: 	Re: coil size for orbits? (fwd)

In a message dated 98-01-19 21:26:06 EST, you write:

> i have just obtained a pile of 10kv 240va orbits. can someone suggest a good
> size coil, cap, torroid, etc for a jr. coil from one or two of these.
> jim heagy


In one design, I used:     A 3" by 12" secondary wound with
#28 formvar magnet wire. Primary was 20 turns of 8281 coax cable in 
30 degree inverted cone design (flat #12 primary with 17 turns would
work just as well because the coax is lossy).  Spark gap was heavy
silver faced contacts which formed a 4 section (four gaps) static gap
assembly, no blown air was used.  Toroid was 5" by 1 1/2" thick.
Spark output was 13" when powered by a 7 amp, 140 volt output
variac.  The capacitor was two .003uF 8kV mica transmitting caps in
series for .0015uF actual.  It gave a nice spark appearance in my

John Freau