Original poster: "Peter Lawrence by way of Terry Fritz <twftesla-at-uswest-dot-net>" <Peter.Lawrence-at-Sun-dot-com> Bart, NICE WORK!!!, I guess this pretty much verifies E-Tesla6 (not that it had not already been), and makes it obvious that there is no rule of thumb (yet!) for the "actual" Ctop given its nominal `Bert Pool' capacitance. -Peter Lawrence.