Re: doorknob cap

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

Original poster: "Ed Phillips by way of Terry Fritz <twftesla-at-qwest-dot-net>" <evp-at-pacbell-dot-net>

Tesla list wrote:
> 
> Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<Mddeming-at-aol-dot-com>
> 
> In a message dated 7/24/01 10:49:47 AM Eastern Daylight Time,
> tesla-at-pupman-dot-com writes:
> 
> >
> > Original poster: "Vinnie by way of Terry Fritz <twftesla-at-qwest-dot-net>" <
> > nickolatesla-at-earthlink-dot-net>
> >
> > Hello People
> >
> >
> > Would anyone happen to know if this is a good buy and if it will produce
> > desired effects. Im new to this and am looking to power a coil with a 15kv
> > 30ma
> > NST and I came accross this item. I am curious if I will be able to obtain
> > any
> > substantial arcs with this cap listed below.
> >
> > Cap. 2000pf, 40kv ceramic, doorknob type. Approximately 2 3/8 inches
> > diameter,
> > and 1 1/4 inches thick with threaded mounting poles (10-32) on each side.
> >
> > Vince


	I use three 0.004 mfd, 15 kV doorknob capacitors here now with a 12 kV,
60 ma transformer and a 14" x 3" secondary.  Get 24"+ streamers, but
have to limit running time to about a minute maximum.  Blew up a couple
of them (punctured and cracked, not sure which came first) until I
realized how hot they were getting.  They have very low resistance and
the dielectric loss don't affect the output much, but you have to be
careful and not overheat them!  I have noticed apparent detuning as they
warm up, but not a serious problem.

	Bottom line is that if you can get them cheaply enough, you will find
that three or four of them in parallel are quite usable until you get
something better.

Ed