----- Original Message ----- 
From: "Randall Pratt" 
To: 
Sent: Thursday, August 12, 2010 8:03 AM
Subject: Re: Farady's Law


> Hi,
> 
> 
> 
> I have experimented with this a bit over the years.  
> 
> The best response for me seems to be a large speaker magnet with added
> center pole into the coil on one end and a stack of neo with added pole
> piece opposing from the other end.  Set up is difficult because of the
> repelling forces, low clearance inside the coil, and arc of swing.  Having a
> U shaped outer pole did not help in the least and may hinder response as
> well as complicate set up.   By the way, I take the face pole iron off of
> the speaker magnet to prevent short circuit of the flux from the center pole
> into the coil.  The inner diameter of the ceramic magnet portion is then
> about the outer diameter of the coil.   I have not tested linearity but I
> use a rather long coil with the poles about 30%  into the coil from each
> end.  I suspect this gives linearity at the expense of some of the end
> windings not receiving full flux.
> 
> 
> 
> Randy
> 
>

It is possible to control magnetic lines of force
focusing etc. and mechanically magnifing the
velocity across the coil by the field.
But you need to involve something like
a soft/granular iron core which affects the resonance and
behavior of the pendulum.
The field lines can snap too and fro
like those sun spots do this time of the
sunspot cycle. I would need a lot more
physics and math in my background
to fully understand this. But i know there are
ways to get a better signal. For the expert pros.
People with money to burn.


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