Re: Secondary Resonance LC and Harmonics.

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Original poster: "Mike" <mike.marcum@xxxxxxxxxxxx>

I would personally just use half the secondary and make 2 4x21's with 1000 
turns each.

Mike
----- Original Message ----- From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Saturday, June 25, 2005 5:46 PM
Subject: Secondary Resonance LC and Harmonics.


> Original poster: "Chris Rutherford" <chris1@xxxxxxxxxxxxxxxxxxx>
>
> Hi All,
>
> I've just wound my first secondary, and in my eagerness I ignored most 
> guidance and just wound as many turns as possible on a piece of 3.5' x 4" 
> tubing.  It turned out to be approximately 2K turns (gulp).
>
> I managed to get my hands on a nice stainless steel sphere, which sits 
> nicely on top.  I was just 'playing' with my scope and signal generator, 
> when I discovered that when I set the sig gen to oscillate at 76KHz or 
> 416KHz I don't need to connect it to the coil in order to show the signal 
> on my scope, I only need to touch the probe and the signal magically gets 
> on to the coil and scope!  - I'm guessing that my coil and top sphere are 
> acting as a tuned LC tank circuit, with a resonant frequency of 76KHz and 
> a harmonic of 416KHz.  Either side of these frequencies the signal drops off.
>
> Does this make sense?  Has anyone else experienced something like this? 
> How *badly* tuned is my coil?  Should I take some turns off it (not yet 
> varnished)?
>
> Thanks
>
> Chris