Click here to see it . Click here to see it . The first arrow points to an arc that is several feet away from the action. It is jumping between the ducting and the metal trim of a doorway. The second arrow points to arcs that shoot along the wall when the streamers hit the wall.
Secondary coil is coated with a few coats of polyurethane.
I had been told that the original secondary was too low in turns and inductance. I had built it before I new of the great resources on the web for Tesla Coils. I measured the resistance of the secondary and it seemed to be twice the calculated resistance. Performance was about the same as the previous revisions, but I couldnt put as large of a topload on it due to the much higher inductance, and not enough turns in the primary. I also have a severe problem of multiple secondary flashovers.