From: "Terrell W. Fritz"
Date: Wed, 22 Nov 2000 14:59:52 -0700
Subject: Re: [TSSP] E-Tesla6.11
Hi Malcolm, At 09:15 AM 11/23/2000 +1300, you wrote: >Hi Terry, > I once heard a description of the top end of the coil as >being a piece of wire flapping in the breeze. I have no doubt at all >that the inductance of those turns is effectively not there in an >unterminated coil because of the current profile. The wire is still a >conductor however. This leads to a number of very interesting points >I would like to put out there for comment. > >#1 - It is known that placing a cut in a terminal plonked hard on top >of the windings affects resonant frequency to only a small degree >given what k must be like between the terminal and those top turns. I >have wondered what the coupling profile must be like (this has direct >relevance to primary coupling as well). Suppose a terminal negates >some of the inductance one would think it adds to the top of the coil >by altering the current profile. Then putting a cut in it such that >it is no longer a shorted turn must alter that effect but it cannot >change the capacitance to any significant degree. Any comments on >that one? I think my other post today address this. I think the top of the coil is rather dead aside from capacitive effects. > >#2 - is your calculated Cself the Medhurst value or the DC value? I simply calculate the capacitance of a cylinder shaped object in the given room. I guess that would be Cself but perhaps the definitions are a bit in disarray at the moment. >Given R. Jones scenario of a distributed L/C being used to calculate >Cself using Tx Line equations gives the measured DC value I found it >fascinating that the lossless case means that the DC value tracks the >Medhurst value exactly proportionately. I also found it fascinating >that using the DC value in this way gives a more realistic (higher) >value for Ctop. I wonder which of the two energy conservation tracks >more accurately? It will be interesting to find out. Yes it will be :-)). Perhaps my other post will shed a little light on all this but right now there are no definite answers. Cheers, Terry > >Regards, >Malcolm > >
Maintainer Paul Nicholson, paul@abelian.demon.co.uk.