Hi Travis,
               I've run several different MMCs now and pushed one to 
operate at its DC rating for five minutes or so at a time with no 
apparent ill effects. The caps were the ones Alan Sharp bought from 
RS components. Using enough parallel strings to observe the dV/dt
rating is the key IMO.


> Original Poster: Travis Tabbal <bigboss-at-xmission-dot-com> 
> The most important thing is that it be pulse rated. They are not
> really very common. Polypropylene pulse caps can be had from Digikey
> and others. Look for values you can make a decent size MMC from. There
> have been a number of various values posted to the list, check the
> archives at www.pupman-dot-com. There is some great data there. Most caps
> are rated in DC volts. No big deal. Many are using DC=AC for the
> rating. The rule of thumb in the past was to go with AC=2*DC. This is
> because AC puts twice the stress on the caps as DC. You have to decide
> for yourself what kind of rating you feel comfortable with. Commerical
> caps are overdesigned, so you can push them a little harder if you
> want.