*To*: Tesla Coil Mailing List <tesla@xxxxxxxxxx>*Subject*: Re: [TCML] tube toploads*From*: brianb@xxxxxxxxxx*Date*: Thu, 22 Jan 2015 10:01:07 -0500*Delivered-to*: teslaarchive@xxxxxxxxxx*Delivered-to*: tesla@xxxxxxxxxx*In-reply-to*: <54C1008D.6040906@earthlink.net>*List-archive*: <http://www.pupman.com/pipermail/tesla/>*List-help*: <mailto:tesla-request@pupman.com?subject=help>*List-id*: Tesla Coil Mailing List <tesla.pupman.com>*List-post*: <mailto:tesla@pupman.com>*List-subscribe*: <http://www.pupman.com/mailman/listinfo/tesla>, <mailto:tesla-request@pupman.com?subject=subscribe>*List-unsubscribe*: <http://www.pupman.com/mailman/options/tesla>, <mailto:tesla-request@pupman.com?subject=unsubscribe>*References*: <54B7CA7D.5050505@earthlink.net> <CA+EoWoizcPKAgxCabhyVVYPWM+gzPmmxP4JcTOizMoPsQRXBtA@mail.gmail.com> <54B7D701.1070704@earthlink.net> <CAFunZhbfaHmmn1u2NQExYiktODmL79knAKrbkNTh67vC5nc2ZQ@mail.gmail.com> <54C0F6B9.40406@earthlink.net> <CA+Vpx0Ha7NLaVukj1Y09ud2i+gHom4e4XXtyjQ69i9q4t4+x0Q@mail.gmail.com> <54C0FDE2.10305@earthlink.net> <54C1008D.6040906@earthlink.net>*Reply-to*: Tesla Coil Mailing List <tesla@xxxxxxxxxx>*Sender*: "Tesla" <tesla-bounces@xxxxxxxxxx>*User-agent*: Roundcube Webmail/1.0.3

Jim/all,

Regards, BrianB On 2015-01-22 08:52, Jim Lux wrote:

On 1/22/15 5:40 AM, Jim Lux wrote:On 1/22/15 5:26 AM, Tim Flood wrote:Yes, just be sure the total surface area of all your tubes is closetothe surface area of the toroid. TimOn Thu, Jan 22, 2015 at 8:10 AM, Jim Lux <jimlux@xxxxxxxxxxxxx>wrote:On 1/22/15 12:30 AM, JoeBonanno wrote:this is an interesting thread! i have to build my own in a few week! For calculating the final capacitance i can use the same formula of solid one? right?That's what I would do. Short of using a finite element tool of some sort.Well.. I would think that the charge on the surface of the tubes thatis"inside" the toroid would be less than the charge on the outside, soona surface area basis, maybe 1/2 the sum of the tube circumferencesmightbe a better approximation.Greg Leyh's Electrum had a tube topload in the shape of a sphere. TheCof a solid sphere is easy to calculate, and if Greg ever measured the tube top load C, we could calibrate with that.Having found some data at http://www.lod.org/Projects/electrum/techdata/electrumspecs.html Greg has his secondary L at 0.13 Henry, and two resonant frequencies, one with topload (7 foot sphere) and one without at 27.92 and 52.60 kHz respectively. Working backwards, that gives a total secondary C of 135.5 pF for "with topload" and 70.4 pF for "without", a difference of 65 pF a 7 foot diameter sphere is 1.06 meters in diameter. I calculate a C for a sphere of that size as 119 pF. That's about twice what would be implied from the frequency shift calculation above. I don't know that this is conclusive (there's a lot of interaction between the field of the topload and the field of the secondary, for instance).. _______________________________________________ Tesla mailing list Tesla@xxxxxxxxxx http://www.pupman.com/mailman/listinfo/tesla

_______________________________________________ Tesla mailing list Tesla@xxxxxxxxxx http://www.pupman.com/mailman/listinfo/tesla

**Follow-Ups**:**Re: [TCML] tube toploads***From:*Jim Lux

**References**:**[TCML] tube toploads***From:*Jim Lux

**Re: [TCML] tube toploads***From:*Tuomas Koivurova

**Re: [TCML] tube toploads***From:*Jim Lux

**Re: [TCML] tube toploads***From:*JoeBonanno

**Re: [TCML] tube toploads***From:*Jim Lux

**Re: [TCML] tube toploads***From:*Tim Flood

**Re: [TCML] tube toploads***From:*Jim Lux

**Re: [TCML] tube toploads***From:*Jim Lux

- Prev by Date:
**Re: [TCML] tube toploads** - Next by Date:
**Re: [TCML] tube toploads** - Previous by thread:
**Re: [TCML] tube toploads** - Next by thread:
**Re: [TCML] tube toploads** - Index(es):