Re: Practical limit to number of turns on primary ? ? ?

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

Original poster: "marc metlicka by way of Terry Fritz <teslalist-at-qwest-dot-net>" <mystuffs-at-orwell-dot-net>



Tesla list wrote:
 >
 > Original poster: "by way of Terry Fritz <teslalist-at-qwest-dot-net>" 
<FutureT-at-aol-dot-com>
 >
 > In a message dated 1/27/03 1:34:26 AM Eastern Standard Time,
 > tesla-at-pupman-dot-com writes:
 >
 > Steve, all,
 >
 > I've found the best efficiency when using a rather large number
 > of primary turns on a small coil.  For example my old research
 > coil used about 18 to 22 turns, and gave 42" sparks from a normal
 > 12/30 NST.  By using a lot of primary turns, the surge impedance
 > is raised, and the gap losses are reduced as a result.  Also, coils
 > with a lot of primary turns probably also have a lot of secondary
 > turns, and this tends to result in a coil which operates at a low
 > frequency.  There is evidence that a lower frequency is effective
 > in producing longer sparks also.  Using a lot of turns may be less
 > important in larger coils which tend to have high surge impedances,
 > and lower frequencies even when using fewer turns, but this seems
 > to be unknown at this time.  Of course if too many turns are used
 > on any coil, it will increase the wire losses due to the high resistance
 > of the thin wire, and the losses will increase too much.  I discuss
 > these issues at my website
 > at:
 > 
<http://hometown.aol-dot-com/futuret/page3.html>http://hometown.aol-dot-com/futuret/page3.html
 > click on the link for "efficiency theory".


  I'm not sure this is the case here? when i built the 3000 turn coil it
uses 24 turns of 1/8" inch primary, the 3' wide primary form assures
coupling to the top of the 42" coil. I'm very impressed with the 2kva
120" discharges compared with the 4' discharges of a 4"-1300 turn coil
placed on the same psu. Also with using many turns of wire will
distribute sharp voltage grandaunt lows over a much broader area, thus
cutting down on mid coil breakout.
  The whole myth of the 1200-1800 turns being optimal only show that not
many coilers are willing to try more!
  With a 6000 turn secondary combined with, a proper primary
construction, could very well surpass my ten footers at 2kva.

By the way, i have never felt secondary heating along the coils.

http://members.fortunecity-dot-com/marcmet/index.htm

Marc M.
 >