Re: Help with TC - Updated

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Esondrmn-at-aol-dot-com>

In a message dated 1/15/02 5:17:43 PM Pacific Standard Time, tesla-at-pupman-dot-com
writes: 


>
> Original poster: "Sean Taylor by way of Terry Fritz <twftesla-at-qwest-dot-net>"
> <taylorss-at-rose-hulman.edu> 
>
> Hi again - A few additions/more information about this coil. 
>
> Currently, I get about 1 or 2 foot sparks into the air, and only around a 
> foot to a grounded rod.  Without a grounded rod there are _many_ streamers 
> coming from the coil - not only the top wire bot the top few turns as well. 
> The capacitors for the MMC are from LLNL (Lawrence Livermore National 
> Laboratory) and are specifically for pulse applications. 
>
> Using the reactance method (calculating the impedance of the transformer and 
> finding the appropriate capacitance to match this impedance), I came up with 
> about 35 nF, how did you arrive at the 0.004 mfd? or is this millifarad 
> (10^-3), and I'm assuming you mean microfarad (10^-6)?  (more prefix 
> problems . . .) 
>
> I definitely want to get a toroid made, however I'm at school right now, in 
> Indiana, and live in California, so my TCs get out on hold for a majority of 
> the year, however, I am trying to start a TC club here at my school (1600 
> undergrad students, all engineering here . . .) 
>
> Also, anyone out there from the SFBA, who would want to try to pool 
> resources for a TC project? 
>
> -Sean Taylor 



Sean, 

I calculated the primary capacitance required for the primary circuit to
resonate at the same frequency as the secondary.  Both primary and secondary
circuits must resonate at the same frequency for the coil to be in tune and
operate efficiently.  Start by calculating the resonant frequency of the
secondary, including toroid if it has one - and it should.  Now calculate (or
measure) the inductance of the primary, then calculate the capacitance required
to match the secondary frequency.  It is best to design it for proper tune at a
turn or two less than the full primary so you have some room left for
adjustments.  Adding a toroid will stop the sparks from leaving from the top
windings of the secondary. 

Ed Sonderman