Re: New coil not working...

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

Original poster: "Dr. Resonance" <resonance-at-jvlnet-dot-com> 


If you connect in beer bottle caps in series, and not in parallel, you have
too little capacitance to bring the primary into resonance.  Try connecting
them in parallel and using a single 25 turn flat spiral scrap wire primary.

It would also be very helpful if you take one of the caps to a local
university (nearby big city or whatever) and ask someone in the Electrical
Engineering lab to measure it's capacitance.  Then you can go to John
Couture's website and run you data in his excellent (and free) computer
program to see where your resonance is.  Then you can adjust the correct
value of capacitance and primary turns to match your sec coils resonance
point.

Keep your variac down to 30% or less while tuning so you don't blow your
xmfr or caps.

Use a good reference ground on the bottom end of your secondary.  Without
this you won't get a proper resonance in the sec coil.  The power line
(green ground wire) is fine for small coils.

Dr. Resonance


 >
 > Well I just made a brand new tesla coil, plugged it in and it doesn't
workl
 > I get nice blue sparks at the spark gaps and a fairly loud electricity
 > noise, but no discharge. First off I would ask for any trouble shooting
 > sites in general that might help?
 >
 > Now for the specifics: I used the wiring shown on this page:
 > http://www.deepfriedneon-dot-com/tesla_frame10.html except that instead of
 > grounding one end of the secondary circuit (as I have not yet constructed
an
 > adequate gorund) I bent it up near the toroid.
 >
 > I have
 > -a 9KV 30 mA transformer
 > -6 beer bottle leyden caps in a series with a close-to-saturated NaCl(aq)
 > solution inside and metal duct tape outside and a layer of oil ranging
from
 > 1/2 - 1 1/2 thick with a brass rod sticking into the solution
 > -a primary coil of three braided enamelled copper magnet wires of #16 gage
 > in 10 flat spiderweb coils about 1/4" apart with an inside diametr of 4"
and
 > an outside diameter of I think 12"
 > -a secondary coil of ~1000 turns #24 gage enamelled copper magnet wire
 > sitting in the centre of the primary coil about 3"- 4" above it
 > -3 spark gaps in a series each of two small brass "L" brakets facing like
 > this: "_| |_" one of which has an adjustable screw
 > -a toroidal discharge terminal of bendable heating duct (ends held
together
 > by a small piece of wood inside screwed into each end around two aluminium
 > pie plates with theri bottoms together.
 > -a currently ungrounded strike rail of ~#18 gage soft iron wire
 >
 > Now I know a host of things could be wrong, and I haven't had time to play
 > with things such as the number of capacitors, the distance of the S.G.
 > screws or the height of the secondary coil above the primary, but this
 > project is due on Monday, and I wanted to present this to you to give you
 > ample time to respond before then, in the case that all I know amounts to
 > nothing. ;) So if anything I am doing jumps out at you as being wrong,
 > please tell me.
 >
 > Thanks in Advance,
 > Greg
 >
 >
 >