RE: 'Nother First Light, but........

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

Original poster: "Pete Komen by way of Terry Fritz <twftesla-at-qwest-dot-net>" <pkomen-at-zianet-dot-com>

Erik,

For a 9/30 NST, the cap should be 0.0088uF, and the Geek Group bucket cap is
(according to the Geeks) rated at 0.0125uF.  Is the decimal place incorrect
on your figure?  0.0125uF would be good for an LTR cap.  I ran a test with
my vacuum static gap and a 9/30 hooked only to the NST protection circuit
and the SG and I got arcs of 0.166 inch (checked with feeler gauge).

Guessing that your primary inner turn is 1" larger radius than the
secondary, I calculate a primary freq of 153.56kHz and a Secondary Freq of
about 108.8kHz.  That is 8.1 inches diameter of the secondary.  I am using
my own Excel spreadsheet calculations and I may be off, but they have been
reliable for my coil.  For that size of secondary, you need more turns on
the primary.

What other spark gap configurations have you tried?  I can recommend AGAINST
brass balls.  The only time I have gotten intermittent arcs across my spark
gap in testing without the TC set up, is when the gap is slightly too large.
1/16 with a 9/30 NST is too small.

Guess I can't answer your question.

Good Luck,

Pete Komen

-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Saturday, June 16, 2001 12:46 PM
To: tesla-at-pupman-dot-com
Subject: 'Nother First Light, but........

Original poster: "Erik Byng by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<e_byng-at-hotmail-dot-com>

Hi there list.

'Nother First Light post. :-)

these just something not quite right, however..
here's the new coil specs..

9kV/30mA Franceformer NST (just untill its tuned, then I switch to a
12kV/60mA)
Single gap SG, with a 12v muffin type fan.  Steel contacts.  Itll be used
untill I find the time to finish the RSG i've got sitting on the garage
floor.
Geek-Group type SW bucket cap -at- roughly 0.119uF.
(or a 0.133uF MMC w/ the 12kV NST)
13 turn primary with 0.25 Copper Tubing, 0.25 inch spacing on 6 PVC
supports.
1036 turn secondary, 8.1" by 28" form, 22awg magnet wire, 11 coats of Behr
"spar varnish" type polyurethane.
Doughnut type toroid, aluminum foil covered w/ 12 inch radius using 3"
aluminum dryer ducting.


Problem is, I have to set the Gap to around a 1/16th of an inch to get any
sort of stable usage.  Any larger than that, and the coil will fire
repeatedly for around 2-3 seconds, the go dead, pause and repeat.  I've
tried the gap, different cap's, coupling etc.

Any hits/suggestions??
Thanks
Erik
"Just say Auuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuugh"
_________________________________________________________________
Get your FREE download of MSN Explorer at http://explorer.msn-dot-com