coil size for orbits? (fwd)
Sent: Tuesday, January 20, 1998 7:51 AM
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