From: Paul
Date: Thu, 16 Aug 2001 10:44:52 +0100
Subject: Re: [TSSP] Anybody there?
Hi Marco, Hope you had a good holiday! Rest assured you've not missed any TSSP activity - things have been very quiet for several weeks. At our end, the hills are open once again, so I've been training lots, barely spending more than an hour or two per week at my desk. It's good to lay off things for a while - helps to give a perspective. There are some plans in the pipeline. You'll recall that attempts to model your's and Terry's secondary base currents looked encouraging, but fell over on the quantitative detail of the higher mode components. This, along with inability to account for the effect of coil former dielectric properties, calls for a different approach to capacitance matrix determination. My plan is to smarten up the boundary element calculations, incorporating some more advanced techniques such as multipole approximation. Amazingly the boundary element method can be reformulated into a Fredholm integral equation of the second kind!!! See the paper by Tausch and White, http://citeseer.nj.nec.com/63237.html My goal now is to rewrite (for the 3rd time!) the capacitance stuff to incorporate these techniques. With luck, we might end up with a program that will cope with the presence of dielectrics, and also allow us to move away from the constraint of cylindrical symmetry. I feel that, once this is done, we'll be determining the capacitance to the best accuracy that the state-of-the-art allows. Also, there is Sullivan's squared-field-derivative method to implement too, which should enable us to predict base input impedances for coils with thin wires. So apart from pondering these issues, I've nothing much to report from this end. The others, it seems, are busy doing interesting things, thus carefully avoiding the thorny issue of absolute top voltage measurement. Cheers, -- Paul Nicholson, Manchester, UK. --
Maintainer Paul Nicholson, paul@abelian.demon.co.uk.