capacitor wanted

["Simon Winder" <swinder-at-microsoft-dot-com> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

Hi everyone...

Anyone know where to get a nice robust 50nF capacitor rated at 15kv or more
that will take lots of rf current?

This is for the plate power supply bypass capacitor on my tube coil. I
currently have a lot of 2nF-at-10kv ceramic in parallel, but they keep blowing
up. This is quite strange as the HT is 4kv and they are not getting hot.

I know about maxwell capacitors but the only place I can find these is at
surplus sales of nebraska, and these seem exceedingly pricey and generally
too big or too high voltage.

thanks
Simon