Pi-Wound RF Chokes

To: tesla-at-poodle.pupman-dot-com
Subject: Pi-Wound RF Chokes
From: Tesla List <tesla-at-stic-dot-net>
Date: Sat, 17 May 1997 01:19:07 -0500
Approved: tesla-at-stic-dot-net

Subject:  Pi-Wound RF Chokes
  Date:   Sat, 17 May 1997 02:51:12 +1000 (EST)
  From:   Rodney Davies <rgd872-at-anu.edu.au>
    To:   tesla-at-pupman-dot-com

Hi all,

Say, I was browsing through an old electronics magazine just today and
came across an article which I read back in '91 on building a small TC.

Anyway, the guy who built the coil noted the use of Pi-wound chokes,
from
what I can remember a friend of mine describing there construction was
as
follows -

Take a 1"x 2" piece of wooden dowell rod.
Machine grooves at spacings of about 1/4" apart (see below)

        |<----------- 2" --------->|       
         __    __    __    __    __   ___  
        |  |  |  |  |  |  |  |  |  |   ^
        |  |__|  |__|  |__|  |__|  |   |
        |   __    __    __    __   |   1"
        |  |  |  |  |  |  |  |  |  |   |
        |__|  |__|  |__|  |__|  |__|  _v_

        |  |           |  |
         ^^^--- 1/4"   ^^^^--- 1/4"

Then wind #30 gauge Cu magnet wire such that you fill each groove, then
when one is full, move onto the next...

Basically, it sort of gives you a series of chokes....
This type of choke is supposively ideal for neon-transformers.

What I'm wondering is has anyone come across this choke design before,
have used it, or know specifically about this particular design and how
it
works as apposed to using a coil of wire around a piece of pipe?

Thanks all, 

Catchya!

Rod