RE: Capacitor Size Limitation

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

Original poster: "Lau, Gary" <gary.lau-at-hp-dot-com> 

When using a static gap, you can generally use up to twice the
mains-resonant cap value, but your 70nF value is still far too large.

And, regardless of the cap's rating, MO caps are designed for 60Hz
filtering, not pulse-discharge duty.  If you did get the value right, I
predict it would toast the wimpy internal connections very quickly.  And
the dielectric is not a premium blend suitable for RF-duty, but more
likely Mylar which will be lossy and get hot.

This is all armchair (though educated) speculation and I'd be delighted
to see you series-up some more to prove me wrong.

Gary Lau
MA, USA



-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Friday, August 29, 2003 10:11 AM
To: tesla-at-pupman-dot-com
Subject: Capacitor Size Limitation

Original poster: "WIZZARD ." <pbobyk-at-hotmail-dot-com>

I originally intended to use a 15KV/60 mA NST and purchased a 10.6 nfd
cap.
I am now using 4, 15KV/30 mA NST transformers and still using the same
capacitor.
Resonant cap should be 21.2 nfd.

I have collected -at- 20 Microwave capacitors from the dump, ranging from
0.7
ufd to 1.2 ufd.
( yup salvaging from the dump is illegal in Canada too, however . . . )

I put 13 of these capacitors in series into a NST case to form a 70 nfd
capacitor.
According to WINTESLA I should be tapped in at turn 5.7 of my 15 turns
of
primary.

I get a very faint hiss of high voltage but no sparks even when the
static
gap is closed to say four of the ten pipes.

I got frustrated and put the 10.6 nfd back in place.

Is there a reason why this arrangement would not work? ( charge time
constant ? )

Should I put more in series to get closer to the LTR 33 nfd ?

Wizzard
Dwight, Ontario
Canada