Re: Results of new single static gap

to: Jim

Even with small coils any type of helix usually results in overcoupling. 
We prefer a flat spiral and then check the coeff. of coupling using
standard techniques.  The copper strap is .030 inch thick x 5/8 inch wide
and is edge wound into slots cut into a piece of white delrin block -- pcs
in all arranged in a circular fashion.  Pri-sec spacing is usually 1 1/2
inches and sec first turn always starts 1 inch above the primary horizontal
plane.  There are different ways to do it but this seems to work best for
us as we have a special jig fabricated to make the slitter cuts on our
lathe.  We can cut a set of 8 pcs in around 10 minutes with the jig.  


> From: Tesla List <tesla-at-pupman-dot-com>
> To: tesla-at-pupman-dot-com
> Subject: Re: Results of new single static gap
> Date: Sunday, August 30, 1998 3:53 PM
> Original Poster: Dsurfr-at-aol-dot-com 
> Dr. Res: Would you be a little more explicit about the copper strapping
> use for your primary coils. I was thinking of switching to a pancake coil
> brass weather stripping (for doors) if I could get a long enough length,
> from many postings on the list I assumed a saucer shaped copper tubing
> was the best way to go. My first primary was a 75 degree helical shape
> from #10 copper ground wire & then I tried a pancake made from coax cable
> had on hand & got better results (with a lot less work in winding!)
> Jim