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

["Tesla list" <tesla@xxxxxxxxxx>]

---------- Forwarded message ----------
Date: Sat, 23 Jun 2007 19:47:43 -0500
From: David Thomson <dwt@xxxxxxxxxxxx>
To: 'Tesla list' <tesla@xxxxxxxxxx>
Subject: RE: A photographic tutorial of Pancake Coil winding...with
    movies...(fwd)

Hi Jeff,

> I saw your interesting Pancake Coil and Cylinder setup.
> There was mention of strong shocks obtained even minutes 
> after powering down.  I have noticed this with all of my 
> Pancakes.  I think it has something to do with the wax and 
> rosin mixtures used in the coils, making a type of 
> Electrophorous.  

This is my thought, too.  The same thing happened with my PVC and oil
encased solenoid coils.  I would like to revisit this sometime and better
understand the physics.

>   I have even placed a cardboard cylinder on top of the 
> Pancake Coils and obtained sparks from the top with a metal 
> electrode of a Wimshurst Machine!  
> The sparks weren't huge, 1/2" or so, but still it was a lot of fun.
> 
> http://www.electrotherapymuseum.com/2007/CardboardStatic/Stati
> cCardboard1.jpg

Yes, I believe this is related to my experiments.  

> As for the cylinder acting like a coil, that's interesting.  
> I did remove the cylinder just now and took more operation 
> photos and the coil worked better.  Perhaps it is just that 
> your theory doesn't match the resonance of the coil according 
> to the cap size I am using.  I wonder if replacing the tube 
> back again and changing the capacitor value would make a 
> marked difference in the discharge?  Any suggestions are more 
> than welcome, in fact I can photograph the Pancake with all 
> 128 combinations of the condenser if you guys want!  That 
> would be fun.

Today I bought some copper and aluminum tubes.  If my thinking is correct,
the longitudinal waves of the solenoids will be calculated according to F =
c / 2L; where F is the frequency, c is the speed of the waves within the
electrons in the tube, and L is the length of the tube.  I plan to use a
frequency generator with a double diode setup as taught to me by Bert
Hickman, and see if I can measure a longitudinal frequency in various
lengths of copper and aluminum tubes.  From this, I should be able to
calculate the speed of the longitudinal waves through the electrons in each
material.  I expect the speed of the waves to differ for aluminum and
copper.  The ballpark for the wave speed through electrons in copper should
be about 1/1000 of the speed of light.

If this works, then we can calculate the longitudinal resonance of the third
coil and match it to the frequency of the secondary/primary setup.
Something to keep in mind is that when the third coil is in resonance, there
is no current leaving the top load.  Instead, there is a standing wave
potential, which produces a unique type of discharge, if allowed to do so.  

The usefulness of this effect is that it produces the longitudinal waves
necessary to transmit wireless power.  It also would have other interesting
uses, which I will discuss at a later time.  

Dave