# Re: (no subject)

Original poster: Mddeming@xxxxxxx
```
```
In a message dated 5/8/06 3:15:46 P.M. Eastern Daylight Time, tesla@xxxxxxxxxx writes:
```Original poster: Jared E Dwarshuis <jdwarshui@xxxxxxxxx>

Hi: Langer

Tesla coils for producing sparks and Tesla coils for energy
transmission are likely tuned differently.

Sorry Matt:

I have not seen a shred of evidence that would suggest that any of the
following is true.

1) Propagation along a coil is not the same as propagation along a
straight wire.
2) Adding a topload drops the operating frequency ~50% and alters the
current distribution.

.......................................................................
......

#1)

Velocity factors from radio handbooks describe the velocity down a
single wire with a ballpark figure of around .95C . Proximity to
ground and other factors presumably change this.

Velocity factors for twin leads become even more complicated. If the
current flows in opposite directions you get a diffrent velocity
factor then if they travelled in the same direction.

Velocity factor also change, when we go from an individual pulse to a
chain of sinusoidal pulses.

The only velocity factor measurements for a  Tesla coil that I am
aware of were made by Paul Nicholson and company. His subsequent
computer simulations for coils with a variety of H/D ratios showed
that the velocity factor could go as high as twice the speed of
light.

(But our experiments demonstrate that this is not true.)
http://www-personal.umich.edu/~mssd/jed/capacitance.html

#2)

We operate coils at the wire length and have found that top end
capacitance requirements are mainly a function of the amount of
current you want to process. Large top ends have not mean a change in
tank frequency.

Large top ends may change the ratio of conduction current to
displacment current, but I would not assume that this alters the
distribution of their sum.

Sincerely: Jared Dwarshuis

Hi Jared,

```
And I've not seen a single shred of evidence that would suggest that any of the counter arguments are true. When faced with such a conflict, one needs to carefully consider both the credibility and credentials of the proponents and detractors of each position to avoid a flame war. With this in mind, I have gone back through the archives to study the evidence, positions, and opinions of Nicholson et.al. and Dwarshuis et.al. over the last few years. After careful consideration and much soul-searching, I find myself siding with Berkeley Breathed's Bill the Cat when he said "THPPFFFTTTT ! ! ! ! "
```
Sincerely,

Matthew D. Deming

```