Re: ebay caps

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

Original poster: Terry Fritz <teslalist-at-twfpowerelectronics-dot-com>

HI,

Higher dissipation caps like mylar may work fine if they are big enough to 
take the current.  Although poly caps are far better, if one uses a big 
enough cap, even the higher loss types will work.  A little warm for a 
mylar cap is probably not too bad.

Filter resistors do get very hot.  Most ceramic tube type resistors 
normally operate at say 300C!  They are often used as space heaters in 
equipment racks where they glow dull red.  I heavily over-rate them just to 
keep the temperatures sane.

Cheers,

         Terry



At 07:00 PM 2/18/2004, you wrote:
>Peter's right!
>
>I run the Fair Radio caps with my 6" coil.  They do heat up, but it does
>take some time.  On the 4th of July, I was running about 1-2 minute runs,
>with about 5 minute cooling periods for about an hour, before letting them
>cool for 30 minutes.  The caps were warm but not "pull your hand away" hot.
>Just give them time to disapate the heat between runs, and they will work
>ok.  During this time I was more worried about the resistor tempature in the
>filter than the caps.
>
>David E Weiss
>
> > Original poster: "Peter Terren" <pterren1-at-iinet-dot-net.au>
> >
> > I wouldn't be too critical of Mylar caps as I know of one set that have
> > lasted 20 years in a 3kW museum coil. They are still lasting although I
>have
> > supplementied them with some Geek group caps since.
> > http://members.iinet-dot-net.au/~pterren/Scitech.htm#Original%20coil
> > Cheers
> > Peter (Tesla Downunder)
> >
> >
> >  > Original poster: "Virtualgod" <mike.marcum-at-zoomtown-dot-com>
> >  >
> >  > It says film, so if it's polyester/mylar it will probably heat up on
>even
> >  > 100-200 watt coils, pushing your luck with higher power.
> > snip
> >
> >
> >