Re: without wires?

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Jim Lux" <jimlux-at-earthlink-dot-net> 

At 05:26 PM 7/24/2004 -0600, you wrote:
>Original poster: "mercurus2000" <mercurus2000-at-cox-dot-net>
>He wasn't gonna transmit power in the way most coilers think, He wanted to
>use the globe and ionosphere as two parts of a spherical capacitor, pumping
>electrical energy into both, and setting up resonance with the schumann
>cavity. It's one of the main reasons why many radio engineers and many
>coilers think his dreams of transmitting power was impossible, they continue
>to think of the Tesla coil as a air core resonant radio antenna, which it
>technically wasn't designed for in the end, Tesla designed it as a
>electromagnetic pump, when coupled with the conductive ionosphere and
>conductive earth, the standard far field laws don't apply since the antenna
>(ionosphere) now completely surrounds all the receiving devices, everyone
>and everything would practically be inside a waveguide connected to Tesla's
>large coil. A experiment I thought to test on a small scale his design was
>to get a metal disk of extremely large diameter, (a few hundred feet or more
>in a large field, connect the top of the coil to this and the ground to of
>course ground, now you'll notice the tubes will light brightly wherever you
>are standing under the large metal disk. Expand the disk and you'll be able
>to draw power from further and further distances. Just now expand this
>design out a few thousand fold and use the ionosphere as the metal disk and
>you'll see what Tesla was talking about. Of course if you have your
>receiving device tuned to the same frequeny of the coil setup, you'll get
>alot more power than just lighting the tube up.
>Adam
>-

we risk straying into verboten list territory here, but...
  Bear in mind that the understanding of the ionosphere back then wasn't 
what it is now. Kennelly Heaviside layer, predicted back in 1902, but 
existence not confirmed until 1923 (by Edward Appleton?)  Tesla did his 
predictions in 1899, but I'm going to guess that he made his prediction of 
frequency  (8 Hz) by knowing the propagation speed of EM radiation (light) 
and the diameter of the earth, rather than by calculating a concentric 
spherical shell resonator.

1) The cavity resonance of the earth ionosphere combination is so low Q 
that this can't work very well. There are two reasons:
a) The earth isn't spherical and, more importantly, the ionosphere has 
widely varying height, so the propagation path is of different heights in 
different places, changing the propagation speed in the waveguide.
b) The walls of the waveguide/cavity are quite lossy.  The ocean surface is 
best, being pretty close to a perfect reflector, but land, polar caps and, 
most particularly, the ionosphere attenuate a lot more than they reflect. 
The path loss is a lot higher than just the distance would indicate. (Los 
Angeles to London, 17000km distance, 1.8 MHz, loss is about 700 dB, for 
August, and SSNs of 18-43... even at the best frequencies (around 20 MHz), 
the path loss is around 190 dB.  Free space path loss between isotropes at 
1.8 MHz would be 122 dB

2) The current flow between the upper atmosphere and earth's surface is 
about 1800 Amps (for the whole earth. (about 3 picoamps/m2).  Since the 
mechanism that drives that fairly small (overall) current is thunderstorms, 
which are a fairly high energy system, it's hard to see that any manmade 
thing is going to significantly change it, and if it DID change it, there 
would probably be lots of unintended side effects.  I note that nuclear 
explosions (particularly high altitude air bursts) DO change the air/earth 
currents, and DO have significant side effects.