Re: bunch of questions

To: tesla-at-poodle.pupman-dot-com
Subject: Re: bunch of questions
From: Tesla List <tesla-at-stic-dot-net>
Date: Sat, 22 Mar 1997 09:27:50 -0600
Approved: tesla-at-stic-dot-net
Subject: 
           Re: bunch of questions
      Date: 
           Fri, 21 Mar 1997 05:50:03 -0500
      From: 
           Steve Falco <sfalco-at-worldnet.att-dot-net>
        To: 
           Tesla List <tesla-at-pupman-dot-com>
References: 
           1


Tesla List wrote:
> 
> Subject:
>         bunch of questions
>   Date:
>         Thu, 20 Mar 1997 17:04:31 -0800
>   From:
>         Calle Laakkonen <laakkone-at-icenet.fi>
>     To:
>         Tesla List <tesla-at-pupman-dot-com>
> 
> Hello all !
> My secondary coil is almost ready and I need some info.
> Should the secondary coil be loose coupled ?
> What size should the primary be when my secondary is about
> 40 inches tall and 4,4 inches in diameter.
> I'm using 28 AWG wire and I need to know is that good size for
> this sized coil ? It 'accidently' got little bigger that I thought.
> How to tune the primary coil ?

Your coil is too long for its diameter.  You should not go over about
5:1 generally; you are nearly at 10:1.  Also #28 is pretty thin.  Most
folks use something closer to #22.

However, all is not lost!  I started with a coil very similar to yours. 
The solution for me was to take a hand saw, and very carefully cut the
coil in half so that I wound up with about 18 inches of windings.  It
was painful, but it was the right thing to do.  Also, you can then use
the left-over top half of your coil as a pair of choke coils to protect
your transformer.  I took the discarded top half, stripped a few inches
of wire off the middle, and had two "free" choke coils - one for each
side of my neon.  I even drilled and bolted a protective spark gap to
the choke coil form for an integrated protection system.  Cut that puppy
down!

In order to determine the primary coil and correct tuning, we also have
to know the size of your main capacitor, (which is determined by the
available power from your transformer).  In other words, all the
components are interrelated.

        Steve Falco
        sfalco-at-worldnet.att-dot-net