[TowerTalk] Tesla's birthday

[jimlux]

Bill Aycock wrote:
> Andy--
> The Tesla coil is really two coils, with the primary usually wound as a flat 
> spiral as a disk at the base of the other, which is a vertical tower. I 
> think that what you are calling a  "Fan" is the primary.
> Bill-W4BSG
> 

Bill is right.  That's a flat spiral or inverted cone primary, and the 4 
"blades" are the supports for the turns. Cardboard on a quick and dirty, 
some nicer insulating material for others (I use HDPE cutting boards).