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Re: New guy questions (fwd)

---------- Forwarded message ----------
Date: Thu, 19 Jul 2007 06:11:06 -0700
From: Jim Lux <jimlux@xxxxxxxxxxxxx>
To: Tesla list <tesla@xxxxxxxxxx>, tesla@xxxxxxxxxx
Subject: Re: New guy questions (fwd)

At 07:55 PM 7/18/2007, Tesla list wrote:

>---------- Forwarded message ----------
>Date: Wed, 18 Jul 2007 21:54:10 -0400
>From: Dan/Elaine G. <degargel@xxxxxxxxxxx>
>To: tesla@xxxxxxxxxx
>Subject: New guy questions
>Hi all,
>I wanted to introduce myself by way of asking a few questions.
>I started getting interested a few months ago, doing some research, starting
>a design, scoring some hardware, and joining the List. Thought I stop
>lurking and ask-away.
>I have also been following the recent FAQ thread btw, and I can understand
>the difficulty such an undertaking might offer, since some of my questions
>focus on some well intentioned yet mildly contradictory input I collected
>from browsing various sites.
>1) How critical is the Secondary HD ratio?  I found some guidance, but I
>also see some folks seem to ditch the convention - for example, maintaining
>an HD of 4 to 4.5 for a 4" coil form. (I haven't run any what-if analysis
>since I've been waiting for the math refresher to hopefully sink into my

Not super critical..  you probably want to stay away from real long 
skinny coils(H/D>10), although they still work.

>2) If I can afford an acrylic/plexiglas over a PVC Sec form, is it worth it?
>(considering dielectric, looks, ease of using an adhesive, etc)

Build your first coil with what ever is easy. The performance 
difference is small between various form materials, and PVC pipe or 
cardboard tubes are easier to come by.  As far as looks go.. you're 
the artist/craftsman, that's up to you.

>3) Best place to score some Cornell Dubilier caps for an mmc: does the Geek
>Group really sell them? to non-members? Should I try eBay or another source?

Geek Group may still sell them.  eBay is a possibility, but make sure 
you're getting the right kind.  You can also just order them from a 

>4) One curiosity question, in my past acquaintance with circularly polarized
>antennae, I was just wondering if there was a winding-sense convention (left
>or right-handed) that applied to coils as well. I've found no such advice
>(probably for an obvious reason). Does it help or not matter at all?

Doesn't matter.
(unless you're winding two coils that you are going to run against each other)

>Too many questions? Reply here or to my address - whatever is better,
>Thanks tons,
>Dan in PA
>I got a variac(!) and a 15/30 NST.