RE: ceramic capacitors

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Lau, Gary" <Gary.Lau@xxxxxx>

Hi Matthew:

There are many different kinds of ceramic dielectrics, some more
suitable for Tesla coil caps than others.  Several people have attempted
to use series/parallel strings of inexpensive ceramic disc capacitors,
and these have all failed miserably.  Ceramic doorknob capacitors come
in several dielectric varieties, and some have been used successfully,
and others run only for a short while before heating up.  Even if the
capacitor does not fail outright, if it gets warm during use, it will
change its capacitance and shift its resonant frequency, so it won't
work well.

I'd recommend forgetting about disk capacitors.  If you happen upon a
fantastic deal on some doorknob caps, they're worth a try, but if they'd
cost you any significant fraction of what a good C-D MMC would cost,
save yourself the heartbreak and skip the ceramic caps.

Regards, Gary Lau
MA, USA


> Original poster: "Matthew Boddicker" <shmerpleton_town@xxxxxxxxxxx>
>
> I have been looking for an aternative for
> cornell-dubilier capacitors for a MMC and I was
> wondering if anyone has any knowledge with high
> voltage ceramic capacitors? My father is an
> electrical engineer and he believes that the
> dielectric should be able to with stand any
> current as long as the capacitor has the right
> voltage rating. He doesn't think that the
> frequency of the circuit could have a damaging effect on the
dielectric.
>
> thanks,
> Matthew Boddicker