Re: top-load size

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

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <FutureT-at-aol-dot-com>

In a message dated 5/25/02 12:56:54 AM Eastern Daylight Time, tesla-at-pupman-dot-com
writes:

Adam,

Yes, it's possible you don't have enough primary turns.  You
may want to use one of the convenient Tesla coil computer
programs such as Bart's JavaTC to figure out how many
turns you actually need.  Looking at the issue in a simple
way though, consider how many primary turns you use 
with the doorknob type topload.  If you are using only 8 turns
for example, then it's likely you won't need more than 11
turns or so when you add the pan-type topload.  In other
words, you'd have enough primary turns.  Now consider a
different possibility.  Maybe you're using 13, 14, or 15 primary
turns when using the doorknob topload.  If this is the case,
then 15 turns is probably not enough when you use the
pan-type topload.   Certainly, you'll need to use more primary
turns with the pan-type topload than with the doorknob-type
topload.   Consider too that you can very easily
see if you need more primary turns.  To find out, simply
add a few more turns using 10awg or 12awg scrap house
wiring.  The wire can be supported with pieces of cardboard
taped in place with scotch tape.  Nothing fancy is needed to
make this test.  Cut away the wire insulation at places so
you can make tap points and tune at various spots to find
the best tune point.   Another possibility, is that the spark output
from your coil is too feeble to break out from the pan toroid, 
although I'd think you'd see at least some sort of corona
display at spots, when viewing in the dark, if the coil is tuned
correctly.

Cheers,
John


>
> I built a big top load (8"pans with ducting im the middle) and when i put it
> on
> my tesla coil, i could not tune my coil so that there would be actual sparks
> coming out of it. Could it possible be that i don't have enough turns of my
> primary? i have 15.  It would just sit there, no sparks, even in the dark.
> Now,
> i am using a (3"?) door knob i found in my house and it works fine. But, i
> would like to have a pie pan, ducting top load.
> Thanks
> Adam