Re: desirability of high coupling...Re: primary INSIDE of secondary?

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

Original poster: "Bunnykiller by way of Terry Fritz <teslalist-at-qwest-dot-net>" <bunikllr-at-bellsouth-dot-net>

  I tried the interior primary setup once...   I ended up with a primary at 
4" outer dia. at 16" tall.  ( 1/4" tubing with .25" spacing  helical 
design   the secondary was 8"X 36" on a lexan form)  approximately 2 turns 
per inch height... for a total of 30 turns primary wise ...   the 
difficulty arose with the tapping process...  had to remove the secondary 
each time to adjust the primary...   wasnt worth the effort...    found 
that the coupling was higher than a conical or flat primary outside the 
secondary ...   I did see increased secondary arc over and arcing from the 
middle/top of the secondary to the top of the primary INSIDE the secondary 
tube....    ruined a really kewl  secondary form... it was powered by 4 
15KV 30mA NST's with the SD linear gap along with 4 Chenelac 10KV .1mF caps 
in series....   output was erratic and maxed out at 36" streamer 
length...    even tho there was approximately 2" clearence between the 
primary and secondary on the inside... the arc-over was still pretty 
predominate...    I went back to the conical primary outside the secondary ....


interior primaries will probably work best with larger secondaries ( 12" 
+)  but in the medium and smaller versions expect serious arc over 
situations ....


Scot D