Re: Help with First Coil (was MMC vs. Maxwell caps)

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

Original poster: "Barton B. Anderson by way of Terry Fritz <twftesla-at-uswest-dot-net>" <tesla123-at-pacbell-dot-net>

Hi Bill,

Ok, the toroid helps.

> Q1: Will the toroid I have suffice?  If not, what would be a good size?

Yes, I think it will suffice. You can always add a bump if there's a break
out problem or throw
together another.

> Q2: Where, approximately, should the primary be tapped, when using two
> 15/60's with a 0.03uF cap, and when using three 15/60's with a 0.045uF
> cap?

With 0.03uF cap, I get a primary tap at 9.27 turns and with 0.045uF, at
about 7.5 turns, so you
are well within range on the primary for running a wide variety of cap
sizes. The transformers
won't make a difference here. Adding more will put more power into the coil
and produce longer
sparklengths. If there is some change, it shouldn't be much.

> Q3: What sort of spark lengths might I expect with the two and three
> NST's, so I'll know when I'm near having it optimally tuned?

Well, hmmm.... Optimally, with 2-15/60's about 72" but considering the
toroid flex duct,
probably about 60". With 3-15/60's, optimal is 88", but again most likely
70". This is using
John Freau's spark length formula: (1.7 * sqrt(watts)).

> All help is greatly appreciated.  When I started playing around with the
> idea of doing this, I don't think I really believed I would, but I'd say
> it's more than half done now, and I'm looking forward to seeing it run.
>
>         Thanks,
>         Bill Vanyo

I see nothing glaring out at me that would be wrong here. Sounds like your
building a coil that
should do well.

Take care,
Bart A.