Re: New 4" Coil: MMC blows MMC Away??

["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: "Jason by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<jasonp-at-btinternet-dot-com>
> 
> Gary,
> 
> > The TDK caps you mention are strontium titanate doorknob (ceramic) caps.
> > The dielectric losses in such caps are surely higher than in suitable
> > polypropylene MMC caps, not to mention the temperature stability issue.  I
> > would doubt that the performance of the doorknob cap would be superior.
> > But aren't both multi-unit arrays of small (MMC) commercial units?
> 
> Yes, temperature stability is an issue - ceramic caps tend to vary in value
> with temperature to a large degree. I had the same doubts as you with
> regards to dielectric loss, but after testing a load of UHV-3A's on my mini
> coil and seeing a performance increase of about 15% I had faith, and bought
> some larger caps of the same series. Now m using 10 UHV-9As, 2nF 40kV each,
> good for about 9ARMS. After a 10 minute run at 300bps on my 1.1kW coil the
> temperature rise measured from the aluminium terminals was negligable
> (educated guess on Pri. current about 40ARMS). Yes, in a way it is an MMC of
> sorts, seeing is it is multiple small value capacitors. I guess I dont call
> it an MMC because it is made of large commercial pulse caps, and not
> hundreds of small value components. All my previous MMCs have been mounted
> on 20mm x 3mm copper bus bar, so the only extra resistance was the MMC cap
> leads, making a fairer comparison.
> 
> Best Regards,
> 
> Jason

	How much did those things cost?

Ed