Re: A photographic tutorial of Pancake Coil winding...with movies...(fwd)

["Tesla list" <tesla@xxxxxxxxxx>]

---------- Forwarded message ----------
Date: Sun, 24 Jun 2007 23:48:35 -0300
From: Antonio Carlos M. de Queiroz <acmdq@xxxxxxxxxx>
To: Tesla list <tesla@xxxxxxxxxx>
Subject: Re: A photographic tutorial of Pancake Coil winding...with
    movies...(fwd)

Tesla list wrote:
> ---------- Forwarded message ----------
> Date: Fri, 22 Jun 2007 07:12:37 -0500
> From: David Thomson <dwt@xxxxxxxxxxxx>
>   
> It may be an opposite perspective, but it is the same thing, either way.
>
> A third coil has no inductive coupling with the secondary and acts like a
> Helmholtz resonator.  
>
> If my understanding is correct, anybody can replace the third coil on their
> magnifier with a copper tube of the same dimensions and get the same
> results.
>
>   
Absolutely not. A tube is just a capacitive load. The third coil of a 
magnifier is a resonator, with a lot of
inductance and distributed capacitance (the distributed capacitance is 
really related to the capacitance
of a metal tube). It is just excited electrically by the connection with 
the secondary coil, not magnetically.

Antonio Carlos M. de Queiroz