Re: GETTING CLOSER!

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

Original poster: "Nathan Morris by way of Terry Fritz <twftesla-at-uswest-dot-net>" <themfam-at-home-dot-com>

Gary,

Thanks for your help. My secondary is wound with # 30 mag and is over 1600
turns.  Sorry for the wire size typo.  (I hope this negates your previously
mentioned primary length issue) When setting up the gaps, using your method,
I take it the secondary doesn't need to be in place.  Sounds like a good
method, one that I will use.

Thanks,

--Nate in Arl. TX

----- Original Message -----
From: Tesla list <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Wednesday, February 21, 2001 9:09 AM
Subject: RE: GETTING CLOSER!


> Original poster: "Lau, Gary by way of Terry Fritz <twftesla-at-uswest-dot-net>"
<Gary.Lau-at-compaq-dot-com>
>
>
>
> >Original poster: "Nathan Morris by way of Terry Fritz
> <twftesla-at-uswest-dot-net>" <themfam-at-home-dot-com>
> >
> >Hello all,
> >This is the current status of my coil and some questions that have come
up
> >along the way.
> >4 x 19 inch Secondary: 1600+ turns of #20 mag wire, complete with a
> modified
> >antique glass insulator for a torroid mount.
> >Primary:  The form is complete and will be wound with close to 50 feet of
> red
> >insulated, stranded 10 AWG.
> >Variac: 3.75 amps 145 VAC out, fused at 10amps and will be used to boost
my
> >tranny. (Will not be used on first light run)
> >Trannys: 2 each 12kv 30ma NSTs. (Only one will be used on first light
run)
> >MMC:  Two rows of four oil filled porcelain caps found on ebay for a
total
> of
> >.01uf.
> >Static gap: 4 pair of contacts, each individually adjustable.
>
> >Questions:
> >1) What is a good distance to set my gaps at for tuning?
>
> The gaps should be set so that WITHOUT the cap in the circuit, the gaps
will
> just fire at maximum NST input.  I would guess a total of 0.2" to 0.25".
> Just be sure to use air blowing across the gaps.
>
> >2) How critical is coupling and what sounds like a reasonable K for me?
>
> All I can say is that it does matter.  Too low and you loose efficiency.
> Too high and you'll destroy your secondary with the "racing sparks"
running
> up and down it.  The only way is to keep increasing k until you get the
> racing sparks, then back off a bit.  Typical k values for a 4" coil may be
> 0.1 - 0.14.
>
> >3) Who would like to sell me a spun aluminum torroid without dents?
> >4) Is there any way to do a low voltage set up first? I have a function
> >generator and a scope and would like to incorporate them into the tuning
> >process.
> >5) Does anyone know where I can find some information on the Teslathon in
> Ft.
> >Worth Texas?
>
> One further comment - If you wind 19" of #20AWG wire, you'd only get about
> 548 turns, not 1600.  A 4" dia coil can (and should) be wound longer to
> achieve a greater separation from topload to ground.  I'd recommend 23"
> long.  To achieve 1600 turns in 23" you'll need to use #27AWG wire.  I'll
> leave it to you to figure out what your primary needs to be to achieve
> matched resonance, but you may need more turns and more than 50 feet.
>
> Good luck,
> Gary Lau
> Waltham, MA USA
>
>
>