From: Paul
Date: Mon, 08 Jan 2001 15:52:27 +0000
Subject: Re: [TSSP] Top voltage testing
Terry, I've altered the model to include an estimate of the area of your partial foil ground plane. The predicted f1 is now 87.92 kHz which agrees with measurement, and the Q has been set to 111.2 by fiddling with the E field loss factor. As a cross check, could you see that the 3/4 wave overtone is at 309.3 kHz +/- 5%. The reason for always asking for f3 and maybe f5 in addition to f1 is to allow us to check that the model is achieving the correct ratio of influence of internal and external capacitance. Without this check we could 'accidentaly' get the right f1. If the proportion of internal C is not correct, then the current profile will be wrong too, thus Lfac and transimpedance will also be out, and voltage gain predictions will be broken too. If f3 matches then that takes care of the model of the toroided un-probed coil, and meanwhile I'll get on with simulating the probe capacitances. FYI, For the equivalent reactances at f1 I get: Lee=70.32 mH; Les=72.61 mH; Ldc=75.10 mH; Cee=43.71 pF; Ces=45.20 pF; Cdc=75.60 pF; Cheers, -- Paul Nicholson, Manchester, UK. --
Maintainer Paul Nicholson, paul@abelian.demon.co.uk.